Bug 599 - FBObject / Offscreen Support - Part 1

- New FBObject implementation handling FBO and it's attachments  *** API CHANGE: Util -> Core ***
  while it's size and sample-count can be reconfigured on the fly.
    - com.jogamp.opengl.util.FBObject -> com.jogamp.opengl.FBObject
    - agnostic to texture unit
    - separate attachments using OO hierarchy reflecting FBO
    - handling MSAA and blitting
    - no FBO destruction for reconfig (attach/detach)

- New GLFBODrawableImpl impl. an FBObject based GLDrawable
   - Instantiated by a dummy native surface (onscreen and invisible)
     hooked up to a dummy GLDrawable, which is the delegation for context creation.

   - Utilizies ProxySurface.UpstreamSurfaceHook for dummy surface
     avoiding specialization for native platforms.

   - TODO: Allow to utilize common surface interface as a
     dummy-surface to supporting API seperation of
     windowing/GL. The latter allows impl. of createGLDrawable(NativeSurface)
     with FBO.

- New OffscreenAutoDrawable (extends GLAutoDrawableDelegate)
  for all offscreen drawables. Shall replace GLPbuffer.

- New GLCapabilities*.isFBO() / setFBO(boolean) to request FBO offscreen,
  similar to isPBuffer(). Rule: if both are requested, FBO shall be favored.

- GLContext adds raw FBO availability query (min. FBO avail),
  FBObject contains fine grained queries (TODO: Move parts to GLContext for efficiency).

- Add framebuffer tracking, allowing fast querying:
  - GLBase/GLContext:
      public int getBoundFramebuffer(int target);
      public int getDefaultDrawFramebuffer();
      public int getDefaultReadFramebuffer();

  - GLContextImpl
      public final void setBoundFramebuffer(int target, int framebufferName)
      .. called by GL impl bind framebuffer

- GL: getDefaultDrawFramebuffer(), getDefaultReadFramebuffer()
  Adding default framebuffer queries being issued by
  GL.glBindFramebuffer(target, 0) w/ a default framebuffer, o.e. zero.
  This allows a transparent use of a custom FBO even in case the applications
  attempts to reset FBO to zero.
    Value flow: GL <- GLContext <- GLDrawable,

- GLCapabilities handle fbo/pbuffer seperate, don't disable the other

- GLContext/GL track read/write framebuffer to be queried by FBObject
  to determine whether to bind/unbind  a framebuffer

- Test cases for multiple FBO w/ and w/o MSAA

Other Features:

- New interface ProxySurface.UpstreamSurfaceHook,
  allowing to hook an upstream surface of unknown type
  providing lifecycle and information (size, ..) callbacks.
  Used for all new dummy NativeSurface impl and SWT GLCanvas.

  - GLContext -> GLDrawable propagation context/drawable lifecycle
    via ProxySurface.UpstreamSurfaceHook allowing dynamic resources
    to react (create, init, ..)
    - contextRealized()
    - contextMadeCurrent()

- SurfaceChangeable -> MutableSurface
  currently only contains setting the surface handle.

  TODO: May need to move ProxySurface.UpstreamSurfaceHook -> MutableSurface.UpstreamSurfaceHook,
        allowing other impl. classes (NEWT OffscreenWindow) to utilize the new
        upstream hookup mechanism - will allow FBO/Dummy window to work.

- SWT GLCanvas using ProxySurface.UpstreamSurfaceHook for proper size
  propagation.

- New GLAutoDrawable::getUpstreamWidget(), allowing GLEventListener
  to fetch the owning Java side UI element (NEWT, SWT, AWT, ..).

- GLDrawableFactory: Removed createOffscreenSurface() - unused and not GL related

- EGLDrawableFactory handles device/profile avail. mapping
  while actually creating context/drawable.
  This allows us to learn whether the ES context is software/hardware as well as FBO avail.

- EGLDrawable: Removed secret buckets of EGL configs :)
  Employ native surface (X11, WGL, ..) to EGL 'mapping' in
  EGLDrawableFactory utilizing new EGLUpstreamSurfaceHook (implements ProxySurface.UpstreamSurfaceHook).

Other Bugs:

- Add CTX_OPTION_DEBUG to ctx/extension cache key since only a debug ctx
  may expose the ARB debug capability.
  This bug caused lack of ARB/AMD debug functionality.

- Fix GLProfile deadlock (debug mode, w/ EGL/ES, no X11),
  dump availability information _after_ lock.

- ImmModeSink draw(): Use GL's glDrawElements(..), don't cast for GL2ES1.
  Fixes use for GL2ES2.

- Fix KeyEvent.getKeyChar() comment (-> only stable for keyTyped(..))

Misc:

- Refined alot of API doc

- New GLExtensions holds commonly used GL extension strings,
  allows better referencing and usage lookup.

- Move GL (interface) decl. to GLBase

- GLBuffers: Cleanup API doc (format, types)

- TextureIO: Add PAM and PPM static suffix identifier

- GLCapabilities getNumSamples() returns 0 if sampleBuffers is disabled, this seems to be more natural.

- finalized a lot

20 files changed, 2368 insertions, 619 deletions

diff --git a/src/jogl/classes/com/jogamp/gluegen/opengl/BuildStaticGLInfo.java b/src/jogl/classes/com/jogamp/gluegen/opengl/BuildStaticGLInfo.java
index 87a734e1f..482d35cae 100644
--- a/src/jogl/classes/com/jogamp/gluegen/opengl/BuildStaticGLInfo.java
+++ b/src/jogl/classes/com/jogamp/gluegen/opengl/BuildStaticGLInfo.java
@@ -293,9 +293,9 @@ public class BuildStaticGLInfo {
         output.println("  public static String getFunctionAssociation(String glFunctionName)");
         output.println("  {");
         output.println("    String mappedName = null;");
-        output.println("    int  funcNamePermNum = com.jogamp.gluegen.runtime.opengl.GLExtensionNames.getFuncNamePermutationNumber(glFunctionName);");
+        output.println("    int  funcNamePermNum = com.jogamp.gluegen.runtime.opengl.GLNameResolver.getFuncNamePermutationNumber(glFunctionName);");
         output.println("    for(int i = 0; null==mappedName && i < funcNamePermNum; i++) {");
-        output.println("        String tmp = com.jogamp.gluegen.runtime.opengl.GLExtensionNames.getFuncNamePermutation(glFunctionName, i);");
+        output.println("        String tmp = com.jogamp.gluegen.runtime.opengl.GLNameResolver.getFuncNamePermutation(glFunctionName, i);");
         output.println("        try {");
         output.println("          mappedName = (String)funcToAssocMap.get(tmp);");
         output.println("        } catch (Exception e) { }");
diff --git a/src/jogl/classes/com/jogamp/gluegen/opengl/GLConfiguration.java b/src/jogl/classes/com/jogamp/gluegen/opengl/GLConfiguration.java
index c1a4facd2..ba025e18c 100755
--- a/src/jogl/classes/com/jogamp/gluegen/opengl/GLConfiguration.java
+++ b/src/jogl/classes/com/jogamp/gluegen/opengl/GLConfiguration.java
@@ -43,7 +43,7 @@ import com.jogamp.gluegen.GlueEmitterControls;
 import com.jogamp.gluegen.GlueGen;
 import com.jogamp.gluegen.MethodBinding;
 import com.jogamp.gluegen.procaddress.ProcAddressConfiguration;
-import com.jogamp.gluegen.runtime.opengl.GLExtensionNames;
+import com.jogamp.gluegen.runtime.opengl.GLNameResolver;
 import java.io.File;
 import java.io.IOException;
 import java.util.ArrayList;
@@ -224,11 +224,11 @@ public class GLConfiguration extends ProcAddressConfiguration {
                     }
                 }
             }
-            boolean isGLEnum = GLExtensionNames.isGLEnumeration(symbol);
-            boolean isGLFunc = GLExtensionNames.isGLFunction(symbol);
+            boolean isGLEnum = GLNameResolver.isGLEnumeration(symbol);
+            boolean isGLFunc = GLNameResolver.isGLFunction(symbol);
             if (isGLFunc || isGLEnum) {
-                if (GLExtensionNames.isExtensionVEN(symbol, isGLFunc)) {
-                    String extSuffix = GLExtensionNames.getExtensionSuffix(symbol, isGLFunc);
+                if (GLNameResolver.isExtensionVEN(symbol, isGLFunc)) {
+                    String extSuffix = GLNameResolver.getExtensionSuffix(symbol, isGLFunc);
                     if (getDropUniqVendorExtensions(extSuffix)) {
                         if (DEBUG_IGNORES) {
                             System.err.println("Ignore UniqVendorEXT: " + symbol + ", vendor " + extSuffix);
diff --git a/src/jogl/classes/com/jogamp/gluegen/opengl/GLEmitter.java b/src/jogl/classes/com/jogamp/gluegen/opengl/GLEmitter.java
index f4658ad7b..809c6783d 100644
--- a/src/jogl/classes/com/jogamp/gluegen/opengl/GLEmitter.java
+++ b/src/jogl/classes/com/jogamp/gluegen/opengl/GLEmitter.java
@@ -51,7 +51,7 @@ import com.jogamp.gluegen.SymbolFilter;
 import com.jogamp.gluegen.cgram.types.FunctionSymbol;
 import com.jogamp.gluegen.procaddress.ProcAddressEmitter;
 import com.jogamp.gluegen.procaddress.ProcAddressJavaMethodBindingEmitter;
-import com.jogamp.gluegen.runtime.opengl.GLExtensionNames;
+import com.jogamp.gluegen.runtime.opengl.GLNameResolver;
 
 import java.io.IOException;
 import java.io.PrintWriter;
@@ -110,13 +110,13 @@ public class GLEmitter extends ProcAddressEmitter {
             if (declarations != null) {
                 for (Iterator<String> iterator = declarations.iterator(); iterator.hasNext();) {
                     String decl = iterator.next();
-                    boolean isGLFunction = GLExtensionNames.isGLFunction(decl);
+                    boolean isGLFunction = GLNameResolver.isGLFunction(decl);
                     boolean isGLEnumeration = false;
                     if (!isGLFunction) {
-                        isGLEnumeration = GLExtensionNames.isGLEnumeration(decl);
+                        isGLEnumeration = GLNameResolver.isGLEnumeration(decl);
                     }
                     if (isGLFunction || isGLEnumeration) {
-                        String renamed = GLExtensionNames.normalize(decl, isGLFunction);
+                        String renamed = GLNameResolver.normalize(decl, isGLFunction);
                         if (!renamed.equals(decl)) {
                             config.addJavaSymbolRename(decl, renamed);
                         }
@@ -181,7 +181,7 @@ public class GLEmitter extends ProcAddressEmitter {
                 String cause = null;
                 for (String decl : declarations) {
                     boolean isFunc = !decl.startsWith("GL_");
-                    if (!GLExtensionNames.isExtension(decl, isFunc)) {
+                    if (!GLNameResolver.isExtension(decl, isFunc)) {
                         isExtension = false;
                         break;
                     }
@@ -199,7 +199,7 @@ public class GLEmitter extends ProcAddressEmitter {
                         }
                     }
                     cause = decl;
-                    String unifiedName = GLExtensionNames.normalize(decl, isFunc);
+                    String unifiedName = GLNameResolver.normalize(decl, isFunc);
                     // NOTE that we look up the unified name in the
                     // BuildStaticGLInfo's notion of the APIs -- since
                     // we might not be emitting glue code for the
@@ -472,12 +472,12 @@ public class GLEmitter extends ProcAddressEmitter {
         w.println("   *   it was statically linked.");
         w.println("   */");
         w.println("  public long getAddressFor(String functionNameUsr) {");
-        w.println("    String functionNameBase = "+GLExtensionNames.class.getName()+".normalizeVEN(com.jogamp.gluegen.runtime.opengl.GLExtensionNames.normalizeARB(functionNameUsr, true), true);");
+        w.println("    String functionNameBase = "+GLNameResolver.class.getName()+".normalizeVEN(com.jogamp.gluegen.runtime.opengl.GLNameResolver.normalizeARB(functionNameUsr, true), true);");
         w.println("    String addressFieldNameBase = PROCADDRESS_VAR_PREFIX + functionNameBase;");
         w.println("    java.lang.reflect.Field addressField = null;");
-        w.println("    int  funcNamePermNum = "+GLExtensionNames.class.getName()+".getFuncNamePermutationNumber(functionNameBase);");
+        w.println("    int  funcNamePermNum = "+GLNameResolver.class.getName()+".getFuncNamePermutationNumber(functionNameBase);");
         w.println("    for(int i = 0; null==addressField && i < funcNamePermNum; i++) {");
-        w.println("        String addressFieldName = "+GLExtensionNames.class.getName()+".getFuncNamePermutation(addressFieldNameBase, i);");
+        w.println("        String addressFieldName = "+GLNameResolver.class.getName()+".getFuncNamePermutation(addressFieldNameBase, i);");
         w.println("        try {");
         w.println("          addressField = getClass().getField(addressFieldName);");
         w.println("        } catch (Exception e) { }");
diff --git a/src/jogl/classes/com/jogamp/gluegen/runtime/opengl/GLExtensionNames.java b/src/jogl/classes/com/jogamp/gluegen/runtime/opengl/GLNameResolver.java
index 426333034..92554776a 100644
--- a/src/jogl/classes/com/jogamp/gluegen/runtime/opengl/GLExtensionNames.java
+++ b/src/jogl/classes/com/jogamp/gluegen/runtime/opengl/GLNameResolver.java
@@ -37,7 +37,8 @@
  */
 package com.jogamp.gluegen.runtime.opengl;
 
-public class GLExtensionNames {
+/** Runtime utility identify and resolve extension names, which may be subsumed to core. */
+public class GLNameResolver {
     //GL_XYZ : GL_XYZ, GL_XYZ_GL2, GL_XYZ_ARB, GL_XYZ_OES, GL_XYZ_OML
     //GL_XYZ : GL_XYZ, GL_GL2_XYZ, GL_ARB_XYZ, GL_OES_XYZ, GL_OML_XYZ
     //
diff --git a/src/jogl/classes/com/jogamp/gluegen/runtime/opengl/GLProcAddressResolver.java b/src/jogl/classes/com/jogamp/gluegen/runtime/opengl/GLProcAddressResolver.java
index fe9efebc7..9775de491 100644
--- a/src/jogl/classes/com/jogamp/gluegen/runtime/opengl/GLProcAddressResolver.java
+++ b/src/jogl/classes/com/jogamp/gluegen/runtime/opengl/GLProcAddressResolver.java
@@ -45,10 +45,10 @@ public class GLProcAddressResolver implements FunctionAddressResolver {
     public long resolve(String name, DynamicLookupHelper lookup) {
 
         long newProcAddress = 0;
-        int permutations = GLExtensionNames.getFuncNamePermutationNumber(name);
+        int permutations = GLNameResolver.getFuncNamePermutationNumber(name);
 
         for (int i = 0; 0 == newProcAddress && i < permutations; i++) {
-            String funcName = GLExtensionNames.getFuncNamePermutation(name, i);
+            String funcName = GLNameResolver.getFuncNamePermutation(name, i);
             try {
                 newProcAddress = lookup.dynamicLookupFunction(funcName);
             } catch (Exception e) {
diff --git a/src/jogl/classes/com/jogamp/opengl/FBObject.java b/src/jogl/classes/com/jogamp/opengl/FBObject.java
new file mode 100644
index 000000000..644d87b1a
--- /dev/null
+++ b/src/jogl/classes/com/jogamp/opengl/FBObject.java
@@ -0,0 +1,1943 @@
+/**
+ * Copyright 2012 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ *
+ *    1. Redistributions of source code must retain the above copyright notice, this list of
+ *       conditions and the following disclaimer.
+ *
+ *    2. Redistributions in binary form must reproduce the above copyright notice, this list
+ *       of conditions and the following disclaimer in the documentation and/or other materials
+ *       provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
+
+package com.jogamp.opengl;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+
+import javax.media.opengl.GL;
+import javax.media.opengl.GL2GL3;
+import javax.media.opengl.GL3;
+import javax.media.opengl.GLBase;
+import javax.media.opengl.GLContext;
+import javax.media.opengl.GLException;
+import javax.media.opengl.GLProfile;
+
+import jogamp.opengl.Debug;
+
+import com.jogamp.opengl.FBObject.Attachment.Type;
+
+/**
+ * Core utility class simplifying usage of framebuffer objects (FBO)
+ * with all {@link GLProfile}s. 
+ * <p>
+ * Supports on-the-fly reconfiguration of dimension and multisample buffers via {@link #reset(GL, int, int, int)}
+ * while preserving the {@link Attachment} references.
+ * </p>
+ * <p>
+ * Integrates default read/write framebuffers via {@link GLContext#getDefaultReadFramebuffer()} and {@link GLContext#getDefaultReadFramebuffer()},
+ * which is being hooked at {@link GL#glBindFramebuffer(int, int)} when the default (<code>zero</code>) framebuffer is selected.
+ * </p>
+ * 
+ * <p>FIXME: Implement support for {@link Type#DEPTH_TEXTURE}, {@link Type#STENCIL_TEXTURE} .</p>
+ */
+public class FBObject {
+    protected static final boolean DEBUG = Debug.debug("FBObject");
+    
+    /** 
+     * Returns <code>true</code> if basic FBO support is available, otherwise <code>false</code>.
+     * <p>
+     * Basic FBO is supported if the context is either GL-ES >= 2.0, GL >= core 3.0 or implements the extensions
+     * <code>ARB_ES2_compatibility</code>, <code>ARB_framebuffer_object</code>, <code>EXT_framebuffer_object</code> or <code>OES_framebuffer_object</code>.
+     * </p>
+     * <p>
+     * Basic FBO support may only include one color attachment and no multisampling,
+     * as well as limited internal formats for renderbuffer.
+     * </p>
+     * @see GLContext#hasFBO()
+     */
+    public static final boolean supportsBasicFBO(GL gl) {
+        return gl.getContext().hasFBO();
+    }
+  
+    /** 
+     * Returns <code>true</code> if full FBO support is available, otherwise <code>false</code>.
+     * <p>
+     * Full FBO is supported if the context is either GL >= core 3.0 or implements the extensions
+     * <code>ARB_framebuffer_object</code>, or all of
+     * <code>EXT_framebuffer_object</code>, <code>EXT_framebuffer_multisample</code>, 
+     * <code>EXT_framebuffer_blit</code>, <code>GL_EXT_packed_depth_stencil</code>.
+     * </p>
+     * <p>
+     * Full FBO support includes multiple color attachments and multisampling.
+     * </p>
+     */
+    public static final boolean supportsFullFBO(GL gl) {
+        return gl.isGL3() ||                                                         // GL >= 3.0
+                
+               gl.isExtensionAvailable(GLExtensions.ARB_framebuffer_object) ||       // ARB_framebuffer_object
+               
+               ( gl.isExtensionAvailable(GLExtensions.EXT_framebuffer_object) &&     // All EXT_framebuffer_object*
+                 gl.isExtensionAvailable(GLExtensions.EXT_framebuffer_multisample) &&
+                 gl.isExtensionAvailable(GLExtensions.EXT_framebuffer_blit) &&
+                 gl.isExtensionAvailable(GLExtensions.EXT_packed_depth_stencil) ) ;
+    }
+    
+    public static final int getMaxSamples(GL gl) {
+        if( supportsFullFBO(gl) ) {
+            int[] val = new int[] { 0 } ;
+            gl.glGetIntegerv(GL2GL3.GL_MAX_SAMPLES, val, 0);
+            return val[0];
+        } else {
+            return 0;
+        }
+    }
+    
+    /** Common super class of all attachments */
+    public static abstract class Attachment {
+        public enum Type { 
+            NONE, DEPTH, STENCIL, DEPTH_STENCIL, COLOR, COLOR_TEXTURE, DEPTH_TEXTURE, STENCIL_TEXTURE;
+            
+            /** 
+             * Returns {@link #COLOR}, {@link #DEPTH}, {@link #STENCIL} or {@link #DEPTH_STENCIL}
+             * @throws IllegalArgumentException if <code>format</code> cannot be handled. 
+             */
+            public static Type determine(int format) throws IllegalArgumentException {
+                switch(format) {
+                    case GL.GL_RGBA4:
+                    case GL.GL_RGB5_A1:
+                    case GL.GL_RGB565:
+                    case GL.GL_RGB8:
+                    case GL.GL_RGBA8:
+                        return Type.COLOR;
+                    case GL.GL_DEPTH_COMPONENT16:
+                    case GL.GL_DEPTH_COMPONENT24:
+                    case GL.GL_DEPTH_COMPONENT32:
+                        return Type.DEPTH;
+                    case GL.GL_STENCIL_INDEX1:
+                    case GL.GL_STENCIL_INDEX4:
+                    case GL.GL_STENCIL_INDEX8:
+                        return Type.STENCIL;
+                    case GL.GL_DEPTH24_STENCIL8:
+                        return Type.DEPTH_STENCIL;
+                    default:
+                        throw new IllegalArgumentException("format invalid: 0x"+Integer.toHexString(format));
+                }        
+            }
+        };
+                
+        /** immutable type [{@link #COLOR}, {@link #DEPTH}, {@link #STENCIL}, {@link #COLOR_TEXTURE}, {@link #DEPTH_TEXTURE}, {@link #STENCIL_TEXTURE} ] */
+        public final Type type;
+        
+        /** immutable the internal format */
+        public final int format;
+        
+        private int width, height;
+        
+        private int name;
+        
+        /** <code>true</code> if resource is initialized by {@link #initialize(GL)}, hence {@link #free(GL)} is allowed to free the GL resources. */
+        protected boolean resourceOwner;
+        
+        private int initCounter;
+        
+        protected Attachment(Type type, int iFormat, int width, int height, int name) {
+            this.type = type;
+            this.format = iFormat;
+            this.width = width;
+            this.height = height;
+            this.name = name;
+            this.resourceOwner = false;
+            this.initCounter = 0;
+        }
+        
+        /** width of attachment */
+        public final int getWidth() { return width; }
+        /** height of attachment */
+        public final int getHeight() { return height; }
+        /* pp */ final void setSize(int w, int h) { width = w; height = h; }
+        
+        /** buffer name [1..max], maybe a texture or renderbuffer name, depending on type. */
+        public final int getName() { return name; }        
+        /* pp */ final void setName(int n) { name = n; }
+        
+        public final int getInitCounter() { return initCounter; }
+        
+        /** 
+         * Initializes the attachment buffer and set it's parameter, if uninitialized, i.e. name is <code>zero</code>.
+         * <p>Implementation employs an initialization counter, hence it can be paired recursively with {@link #free(GL)}.</p>
+         * @throws GLException if buffer generation or setup fails. The just created buffer name will be deleted in this case. 
+         */
+        public void initialize(GL gl) throws GLException {
+            initCounter++;
+            /*
+            super.initialize(gl);
+            if(1 == getInitCounter() && 0 == getName()  ) {
+                do init ..
+                freeResources = true; // if all OK
+            }
+            */
+        }
+        
+        /** 
+         * Releases the attachment buffer if initialized, i.e. name is <code>zero</code>.
+         * <p>Implementation employs an initialization counter, hence it can be paired recursively with {@link #initialize(GL)}.</p>
+         * @throws GLException if buffer release fails. 
+         */
+        public void free(GL gl) throws GLException {
+            /*
+            if(1 == getInitCounter() && freeResources && .. ) {
+                do free ..
+            }
+            super.free(gl);
+            */
+            initCounter--;
+            if(0 == initCounter) {
+                resourceOwner = false;
+                name = 0;
+            }
+            if(DEBUG) {
+                System.err.println("Attachment.free: "+this);
+            }
+        }
+        
+        /**
+         * <p>
+         * Comparison by {@link #type}, {@link #format}, {@link #width}, {@link #height} and {@link #name}.
+         * </p>
+         * {@inheritDoc}
+         */
+        @Override
+        public boolean equals(Object o) {
+            if( this == o ) return true;
+            if( ! ( o instanceof Attachment ) ) return false;
+            final Attachment a = (Attachment)o;
+            return type == a.type &&
+                   format == a.format ||
+                   width == a.width   ||
+                   height== a.height  ||
+                   name == a.name     ;
+        }
+        
+        /**
+         * <p>
+         * Hashed by {@link #type}, {@link #format}, {@link #width}, {@link #height} and {@link #name}.
+         * </p>
+         * {@inheritDoc}
+         */
+        @Override
+        public int hashCode() {
+            // 31 * x == (x << 5) - x
+            int hash = 31 + type.ordinal();
+            hash = ((hash << 5) - hash) + format;
+            hash = ((hash << 5) - hash) + width;
+            hash = ((hash << 5) - hash) + height;
+            hash = ((hash << 5) - hash) + name;
+            return hash;
+        }
+        
+        int objectHashCode() { return super.hashCode(); }
+        
+        public String toString() {
+            return getClass().getSimpleName()+"[type "+type+", format 0x"+Integer.toHexString(format)+", "+width+"x"+height+
+                   ", name 0x"+Integer.toHexString(name)+", obj 0x"+Integer.toHexString(objectHashCode())+
+                   ", resOwner "+resourceOwner+", initCount "+initCounter+"]";
+        }
+        
+        public static Type getType(int attachmentPoint, int maxColorAttachments) {
+            if( GL.GL_COLOR_ATTACHMENT0 <= attachmentPoint && attachmentPoint < GL.GL_COLOR_ATTACHMENT0+maxColorAttachments ) {
+                return Type.COLOR;
+            }
+            switch(attachmentPoint) {
+                case GL.GL_DEPTH_ATTACHMENT:
+                    return Type.DEPTH;
+                case GL.GL_STENCIL_ATTACHMENT:            
+                    return Type.STENCIL;
+                default: 
+                    throw new IllegalArgumentException("Invalid attachment point 0x"+Integer.toHexString(attachmentPoint));
+            }
+        }
+    }
+    
+    /** Other renderbuffer attachment which maybe a colorbuffer, depth or stencil. */
+    public static class RenderAttachment extends Attachment {
+        private int samples;
+        
+        /**
+         * @param type allowed types are {@link Type#DEPTH}, {@link Type#STENCIL} or {@link Type#COLOR}
+         * @param iFormat
+         * @param samples
+         * @param width
+         * @param height
+         * @param name
+         */
+        public RenderAttachment(Type type, int iFormat, int samples, int width, int height, int name) {
+            super(validateType(type), iFormat, width, height, name);
+            this.samples = samples;
+        }
+        
+        /** number of samples, or zero for no multisampling */
+        public final int getSamples() { return samples; }
+        /* pp */ final void setSamples(int s) { samples = s; }
+        
+        private static Type validateType(Type type) {
+            switch(type) {
+                case DEPTH:
+                case STENCIL:
+                case COLOR:
+                    return type;
+                default: 
+                    throw new IllegalArgumentException("Invalid type: "+type);
+            }
+        }
+        
+        /**
+         * <p>
+         * Comparison by {@link #type}, {@link #format}, {@link #samples}, {@link #width}, {@link #height} and {@link #name}.
+         * </p>
+         * {@inheritDoc}
+         */
+        @Override
+        public boolean equals(Object o) {
+            if( this == o ) return true;
+            if( ! ( o instanceof RenderAttachment ) ) return false;
+            return super.equals(o) &&
+                   samples == ((RenderAttachment)o).samples;
+        }
+        
+        /**
+         * <p>
+         * Hashed by {@link #type}, {@link #format}, {@link #samples}, {@link #width}, {@link #height} and {@link #name}.
+         * </p>
+         * {@inheritDoc}
+         */
+        @Override
+        public int hashCode() {
+            // 31 * x == (x << 5) - x
+            int hash = super.hashCode();
+            hash = ((hash << 5) - hash) + samples;
+            return hash;
+        }
+
+        @Override
+        public void initialize(GL gl) throws GLException {
+            super.initialize(gl);
+            if( 1 == getInitCounter() && 0 == getName() ) {
+                final int[] name = new int[] { -1 };
+                gl.glGenRenderbuffers(1, name, 0);
+                if( 0 == name[0] ) {
+                    throw new GLException("null renderbuffer, "+this);
+                }
+                setName(name[0]);
+                
+                gl.glBindRenderbuffer(GL.GL_RENDERBUFFER, getName());
+                if( samples > 0 ) {
+                    ((GL2GL3)gl).glRenderbufferStorageMultisample(GL.GL_RENDERBUFFER, samples, format, getWidth(), getHeight());            
+                } else {
+                    gl.glRenderbufferStorage(GL.GL_RENDERBUFFER, format, getWidth(), getHeight());
+                }
+                int glerr = gl.glGetError();
+                if(GL.GL_NO_ERROR != glerr) {
+                    gl.glDeleteRenderbuffers(1, name, 0);
+                    setName(0);
+                    throw new GLException("GL Error 0x"+Integer.toHexString(glerr)+" while creating "+this);
+                }
+                resourceOwner = true;
+                if(DEBUG) {
+                    System.err.println("Attachment.init: "+this);
+                }
+            }
+        }
+        
+        @Override
+        public void free(GL gl) {
+            if(1 == getInitCounter() && resourceOwner && 0 != getName() ) {
+                final int[] name = new int[] { getName() };
+                gl.glDeleteRenderbuffers(1, name, 0);
+            }
+            super.free(gl);
+        }
+        
+        public String toString() {
+            return getClass().getSimpleName()+"[type "+type+", format 0x"+Integer.toHexString(format)+", samples "+samples+", "+getWidth()+"x"+getHeight()+
+                   ", name 0x"+Integer.toHexString(getName())+", obj 0x"+Integer.toHexString(objectHashCode())+
+                   ", resOwner "+resourceOwner+", initCount "+getInitCounter()+"]";
+        }
+    }
+    
+    /** 
+     * Marker interface, denotes a color buffer attachment.
+     * <p>Always an instance of {@link Attachment}.</p>
+     * <p>Either an instance of {@link ColorAttachment} or {@link TextureAttachment}.</b> 
+     */
+    public static interface Colorbuffer {        
+    }
+    
+    /** Color render buffer attachment  */
+    public static class ColorAttachment extends RenderAttachment implements Colorbuffer {
+        public ColorAttachment(int iFormat, int samples, int width, int height, int name) {
+            super(Type.COLOR, iFormat, samples, width, height, name);
+        }    
+    }
+    
+    /** Texture attachment */
+    public static class TextureAttachment extends Attachment implements Colorbuffer  {
+        /** details of the texture setup */
+        public final int dataFormat, dataType, magFilter, minFilter, wrapS, wrapT;
+
+        /**
+         * @param type allowed types are [ {@link Type#COLOR_TEXTURE}, {@link Type#DEPTH_TEXTURE}, {@link Type#STENCIL_TEXTURE} ]
+         * @param iFormat
+         * @param width
+         * @param height
+         * @param dataFormat
+         * @param dataType
+         * @param magFilter
+         * @param minFilter
+         * @param wrapS
+         * @param wrapT
+         * @param name
+         */
+        public TextureAttachment(Type type, int iFormat, int width, int height, int dataFormat, int dataType, 
+                                 int magFilter, int minFilter, int wrapS, int wrapT, int name) {
+            super(validateType(type), iFormat, width, height, name);
+            this.dataFormat = dataFormat;
+            this.dataType = dataType;
+            this.magFilter = magFilter;
+            this.minFilter = minFilter;
+            this.wrapS = wrapS;
+            this.wrapT = wrapT;
+        }
+        
+        private static Type validateType(Type type) {
+            switch(type) {
+                case COLOR_TEXTURE:
+                case DEPTH_TEXTURE:
+                case STENCIL_TEXTURE:
+                    return type;
+                default: 
+                    throw new IllegalArgumentException("Invalid type: "+type);
+            }
+        }
+        
+        /** 
+         * Initializes the texture and set it's parameter, if uninitialized, i.e. name is <code>zero</code>.
+         * @throws GLException if texture generation and setup fails. The just created texture name will be deleted in this case. 
+         */
+        @Override
+        public void initialize(GL gl) throws GLException {
+            super.initialize(gl);
+            if( 1 == getInitCounter() && 0 == getName() ) {
+                final int[] name = new int[] { -1 };            
+                gl.glGenTextures(1, name, 0);
+                if(0 == name[0]) {
+                    throw new GLException("null texture, "+this);
+                }
+                setName(name[0]);
+                
+                gl.glBindTexture(GL.GL_TEXTURE_2D, name[0]);
+                gl.glTexImage2D(GL.GL_TEXTURE_2D, 0, format, getWidth(), getHeight(), 0, dataFormat, dataType, null);
+                if( 0 < magFilter ) {
+                    gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MAG_FILTER, magFilter);
+                }
+                if( 0 < minFilter ) {
+                    gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MIN_FILTER, minFilter);
+                }
+                if( 0 < wrapS ) {
+                    gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_S, wrapS);
+                }
+                if( 0 < wrapT ) {
+                    gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_T, wrapT);            
+                }        
+                int glerr = gl.glGetError();
+                if(GL.GL_NO_ERROR != glerr) {
+                    gl.glDeleteTextures(1, name, 0);
+                    setName(0);
+                    throw new GLException("GL Error 0x"+Integer.toHexString(glerr)+" while creating "+this);
+                }
+                resourceOwner = true;
+            }
+            if(DEBUG) {
+                System.err.println("Attachment.init: "+this);
+            }
+        }
+
+        @Override
+        public void free(GL gl) {
+            if(1 == getInitCounter() && resourceOwner && 0 != getName() ) {
+                final int[] name = new int[] { getName() };
+                gl.glDeleteTextures(1, name, 0);
+            }
+            super.free(gl);
+        }
+    }
+    
+    private boolean initialized;
+    private boolean basicFBOSupport;
+    private boolean fullFBOSupport;
+    private boolean rgba8Avail;
+    private boolean depth24Avail;
+    private boolean depth32Avail;
+    private boolean stencil01Avail;
+    private boolean stencil04Avail;
+    private boolean stencil08Avail;
+    private boolean stencil16Avail;
+    private boolean packedDepthStencilAvail;            
+    private int maxColorAttachments, maxSamples, maxTextureSize, maxRenderbufferSize;
+
+    private int width, height, samples;
+    private int vStatus;
+    private int fbName;
+    private boolean bound;
+
+    private int colorAttachmentCount;
+    private Colorbuffer[] colorAttachmentPoints; // colorbuffer attachment points 
+    private RenderAttachment depth, stencil; // depth and stencil maybe equal in case of packed-depth-stencil
+
+    private final FBObject samplesSink; // MSAA sink
+    private TextureAttachment samplesSinkTexture; 
+    private boolean samplesSinkDirty;
+
+    //
+    // ColorAttachment helper ..
+    //
+    
+    private final void validateColorAttachmentPointRange(int point) {
+        if(maxColorAttachments != colorAttachmentPoints.length) {
+            throw new InternalError("maxColorAttachments "+maxColorAttachments+", array.lenght "+colorAttachmentPoints);
+        }
+        if(0 > point || point >= maxColorAttachments) {
+            throw new IllegalArgumentException("attachment point out of range: "+point+", should be within [0.."+(maxColorAttachments-1)+"]");
+        }
+    }
+    
+    private final void validateAddColorAttachment(int point, Colorbuffer ca) {
+        validateColorAttachmentPointRange(point);
+        if( null != colorAttachmentPoints[point] ) {
+            throw new IllegalArgumentException("Cannot attach "+ca+", attachment point already in use by "+colorAttachmentPoints[point]);
+        }        
+    }
+    
+    private final void addColorAttachment(int point, Colorbuffer ca) {
+        validateColorAttachmentPointRange(point);
+        final Colorbuffer c = colorAttachmentPoints[point];
+        if( null != c && c != ca ) {
+            throw new IllegalArgumentException("Add failed: requested to add "+ca+" at "+point+", but slot is holding "+c+"; "+this);
+        }
+        colorAttachmentPoints[point] = ca;
+        colorAttachmentCount++;
+    }
+    
+    private final void removeColorAttachment(int point, Colorbuffer ca) {
+        validateColorAttachmentPointRange(point);
+        final Colorbuffer c = colorAttachmentPoints[point];
+        if( null != c && c != ca ) {
+            throw new IllegalArgumentException("Remove failed: requested to removed "+ca+" at "+point+", but slot is holding "+c+"; "+this);
+        }
+        colorAttachmentPoints[point] = null;
+        colorAttachmentCount--;
+    }
+    
+    /**
+     * Return the {@link Colorbuffer} attachment at <code>attachmentPoint</code> if it is attached to this FBO, otherwise null.
+     * 
+     * @see #attachColorbuffer(GL, boolean)
+     * @see #attachColorbuffer(GL, boolean)
+     * @see #attachTexture2D(GL, int, boolean, int, int, int, int)
+     * @see #attachTexture2D(GL, int, int, int, int, int, int, int, int) 
+     */
+    public final Colorbuffer getColorbuffer(int attachmentPoint) {
+        validateColorAttachmentPointRange(attachmentPoint);        
+        return colorAttachmentPoints[attachmentPoint];
+    }
+    
+    /**
+     * Finds the passed {@link Colorbuffer} within the valid range of attachment points
+     * using <i>reference</i> comparison only.
+     * <p>
+     * Note: Slow. Implementation uses a logN array search to save resources, i.e. not using a HashMap.
+     * </p>
+     * @param ca the {@link Colorbuffer} to look for.
+     * @return -1 if the {@link Colorbuffer} could not be found, otherwise [0..{@link #getMaxColorAttachments()}-1] 
+     */
+    public final int getColorbufferAttachmentPoint(Colorbuffer ca) {
+        for(int i=0; i<colorAttachmentPoints.length; i++) {
+            if( colorAttachmentPoints[i] == ca ) {
+                return i; 
+            }
+        }
+        return -1;
+    }
+    
+    /**
+     * Returns the passed {@link Colorbuffer} if it is attached to this FBO, otherwise null.
+     * Implementation compares the <i>reference</i> only.
+     * 
+     * <p>
+     * Note: Slow. Uses {@link #getColorbufferAttachmentPoint(Colorbuffer)} to determine it's attachment point
+     *       to be used for {@link #getColorbuffer(int)}
+     * </p>
+     * 
+     * @see #attachColorbuffer(GL, boolean)
+     * @see #attachColorbuffer(GL, boolean)
+     * @see #attachTexture2D(GL, int, boolean, int, int, int, int)
+     * @see #attachTexture2D(GL, int, int, int, int, int, int, int, int) 
+     */
+    public final Colorbuffer getColorbuffer(Colorbuffer ca) {
+        final int p = getColorbufferAttachmentPoint(ca);
+        return p>=0 ? getColorbuffer(p) : null;
+    }
+        
+    /**
+     * Creates an uninitialized FBObject instance.
+     * <p>
+     * Call {@link #init(GL, int, int, int)} .. etc to use it.
+     * </p>
+     */
+    public FBObject() {
+        this(false);
+    }
+    /* pp */ FBObject(boolean isSampleSink) {
+        this.initialized = false;
+        
+        // TBD @ init
+        this.basicFBOSupport = false;
+        this.fullFBOSupport = false;
+        this.rgba8Avail = false;
+        this.depth24Avail = false;
+        this.depth32Avail = false;
+        this.stencil01Avail = false;
+        this.stencil04Avail = false;
+        this.stencil08Avail = false;
+        this.stencil16Avail = false;
+        this.packedDepthStencilAvail = false;
+        this.maxColorAttachments=-1;
+        this.maxSamples=-1;
+        this.maxTextureSize = 0;
+        this.maxRenderbufferSize = 0;
+        
+        this.width = 0;
+        this.height = 0;
+        this.samples = 0;
+        this.vStatus = -1;        
+        this.fbName = 0;
+        this.bound = false;
+        
+        this.colorAttachmentPoints = null; // at init ..
+        this.colorAttachmentCount = 0;
+        this.depth = null;
+        this.stencil = null;                
+        
+        this.samplesSink = isSampleSink ? null : new FBObject(true);
+        this.samplesSinkTexture = null;
+        this.samplesSinkDirty = true;
+    }
+    
+    private void init(GL gl, int width, int height, int samples) throws GLException {
+        if(initialized) {
+            throw new GLException("FBO already initialized");
+        }        
+        fullFBOSupport = supportsFullFBO(gl);
+        
+        if( !fullFBOSupport && !supportsBasicFBO(gl) ) {
+            throw new GLException("FBO not supported w/ context: "+gl.getContext()+", "+this);
+        }
+        
+        basicFBOSupport = true;
+        
+        rgba8Avail = gl.isGL2GL3() || gl.isExtensionAvailable(GLExtensions.OES_rgb8_rgba8);
+        depth24Avail = fullFBOSupport || gl.isExtensionAvailable(GLExtensions.OES_depth24);
+        depth32Avail = fullFBOSupport || gl.isExtensionAvailable(GLExtensions.OES_depth32);
+        stencil01Avail = fullFBOSupport || gl.isExtensionAvailable(GLExtensions.OES_stencil1);
+        stencil04Avail = fullFBOSupport || gl.isExtensionAvailable(GLExtensions.OES_stencil4);
+        stencil08Avail = fullFBOSupport || gl.isExtensionAvailable(GLExtensions.OES_stencil8);
+        stencil16Avail = fullFBOSupport;
+        
+        packedDepthStencilAvail = fullFBOSupport || gl.isExtensionAvailable(GLExtensions.OES_packed_depth_stencil);
+        
+        final boolean NV_fbo_color_attachments = gl.isExtensionAvailable(GLExtensions.NV_fbo_color_attachments);
+                                
+        int val[] = new int[1];
+        
+        int glerr = gl.glGetError();
+        if(DEBUG && GL.GL_NO_ERROR != glerr) {
+            System.err.println("FBObject.init-preexisting.0 GL Error 0x"+Integer.toHexString(glerr));
+        }
+
+        int realMaxColorAttachments = 1;
+        maxColorAttachments = 1;
+        if( null != samplesSink && fullFBOSupport || NV_fbo_color_attachments ) {
+            try {
+                gl.glGetIntegerv(GL2GL3.GL_MAX_COLOR_ATTACHMENTS, val, 0);
+                glerr = gl.glGetError();
+                if(GL.GL_NO_ERROR == glerr) {
+                    realMaxColorAttachments = 1 <= val[0] ? val[0] : 1; // cap minimum to 1
+                } else if(DEBUG) {
+                    System.err.println("FBObject.init-GL_MAX_COLOR_ATTACHMENTS query GL Error 0x"+Integer.toHexString(glerr));
+                }
+            } catch (GLException gle) {}
+        }
+        maxColorAttachments = realMaxColorAttachments <= 8 ? realMaxColorAttachments : 8; // cap to limit array size
+        
+        colorAttachmentPoints = new Colorbuffer[maxColorAttachments];
+        colorAttachmentCount = 0;
+        
+        maxSamples = 0;
+        if(fullFBOSupport) {
+            gl.glGetIntegerv(GL2GL3.GL_MAX_SAMPLES, val, 0);
+            glerr = gl.glGetError();
+            if(GL.GL_NO_ERROR == glerr) {
+                maxSamples = val[0];
+            } else if(DEBUG) {
+                System.err.println("FBObject.init-GL_MAX_SAMPLES query GL Error 0x"+Integer.toHexString(glerr));
+            }
+        }
+        gl.glGetIntegerv(GL.GL_MAX_TEXTURE_SIZE, val, 0);
+        maxTextureSize = val[0];
+        gl.glGetIntegerv(GL.GL_MAX_RENDERBUFFER_SIZE, val, 0);
+        this.maxRenderbufferSize = val[0];
+        
+        glerr = gl.glGetError();
+        if(DEBUG && GL.GL_NO_ERROR != glerr) {
+            System.err.println("FBObject.init-preexisting.1 GL Error 0x"+Integer.toHexString(glerr));
+        }
+        
+        this.width = width;
+        this.height = height;
+        this.samples = samples <= maxSamples ? samples : maxSamples;
+        
+        if(DEBUG) {
+            System.err.println("FBObject "+width+"x"+height+", "+samples+" -> "+samples+" samples");
+            System.err.println("basicFBOSupport:          "+basicFBOSupport);
+            System.err.println("fullFBOSupport:           "+fullFBOSupport);
+            System.err.println("maxColorAttachments:      "+maxColorAttachments+"/"+realMaxColorAttachments);
+            System.err.println("maxSamples:               "+maxSamples);
+            System.err.println("maxTextureSize:           "+maxTextureSize);
+            System.err.println("maxRenderbufferSize:      "+maxRenderbufferSize);
+            System.err.println("rgba8:                    "+rgba8Avail);
+            System.err.println("depth24:                  "+depth24Avail);
+            System.err.println("depth32:                  "+depth32Avail);
+            System.err.println("stencil01:                "+stencil01Avail);
+            System.err.println("stencil04:                "+stencil04Avail);
+            System.err.println("stencil08:                "+stencil08Avail);
+            System.err.println("stencil16:                "+stencil16Avail);
+            System.err.println("packedDepthStencil:       "+packedDepthStencilAvail);
+            System.err.println("NV_fbo_color_attachments: "+NV_fbo_color_attachments);
+            System.err.println(gl.getContext().getGLVersion());
+            System.err.println(JoglVersion.getGLStrings(gl, null).toString());
+            System.err.println(gl.getContext());
+        }
+        
+        checkNoError(null, gl.glGetError(), "FBObject Init.pre"); // throws GLException if error
+        
+        if(width > 2 + maxTextureSize  || height> 2 + maxTextureSize ||
+           width > maxRenderbufferSize || height> maxRenderbufferSize  ) {
+            throw new GLException("size "+width+"x"+height+" exceeds on of the maxima [texture "+maxTextureSize+", renderbuffer "+maxRenderbufferSize+"]");
+        }
+
+        if(null != samplesSink) {        
+            // init sampling sink
+            samplesSink.reset(gl, width, height);
+            resetMSAATexture2DSink(gl);
+        }
+
+        // generate fbo ..
+        gl.glGenFramebuffers(1, val, 0);
+        fbName = val[0];
+        if(0 == fbName) {
+            throw new GLException("null framebuffer");
+        }
+
+        // bind fbo ..
+        gl.glBindFramebuffer(GL.GL_FRAMEBUFFER, fbName);        
+        checkNoError(gl, gl.glGetError(), "FBObject Init.bindFB");  // throws GLException if error        
+        if(!gl.glIsFramebuffer(fbName)) {
+            checkNoError(gl, GL.GL_INVALID_VALUE, "FBObject Init.isFB"); // throws GLException
+        }
+        bound = true;        
+        initialized = true;
+        
+        updateStatus(gl);
+        if(DEBUG) {
+            System.err.println("FBObject.init(): "+this);
+        }
+    }
+
+    /**
+     * Initializes or resets this FBO's instance.
+     * <p>
+     * In case the new parameters are compatible with the current ones
+     * no action will be performed. Otherwise all attachments will be recreated
+     * to match the new given parameters.
+     * </p>
+     * <p>
+     * Currently incompatibility and hence recreation is given if
+     * the size or sample count doesn't match for subsequent calls.
+     * </p>
+     * 
+     * <p>Leaves the FBO bound state untouched</p>
+     * 
+     * @param gl the current GL context
+     * @param newWidth
+     * @param newHeight
+     * @throws GLException in case of an error
+     */
+    public final void reset(GL gl, int newWidth, int newHeight) {
+        reset(gl, newWidth, newHeight, 0);
+    }
+    
+    /**
+     * Initializes or resets this FBO's instance.
+     * <p>
+     * In case the new parameters are compatible with the current ones
+     * no action will be performed. Otherwise all attachments will be recreated
+     * to match the new given parameters.
+     * </p>
+     * <p>
+     * Currently incompatibility and hence recreation is given if
+     * the size or sample count doesn't match for subsequent calls.
+     * </p>
+     * 
+     * <p>Leaves the FBO bound state untouched</p>
+     * 
+     * @param gl the current GL context
+     * @param newWidth
+     * @param newHeight
+     * @param newSamples if > 0, MSAA will be used, otherwise no multisampling. Will be capped to {@link #getMaxSamples()}.
+     * @throws GLException in case of an error
+     */
+    public final void reset(GL gl, int newWidth, int newHeight, int newSamples) {
+        if(!initialized) {
+            init(gl, newWidth, newHeight, newSamples);
+            return;
+        }
+        newSamples = newSamples <= maxSamples ? newSamples : maxSamples; // clamp
+        
+        if( newWidth !=  width || newHeight !=  height || newSamples != samples ) {
+            if(DEBUG) {
+                System.err.println("FBObject.reset - START - "+this);
+            }        
+            
+            final boolean wasBound = isBound();
+            
+            width = newWidth;
+            height = newHeight;
+            samples = newSamples;
+            detachAllImpl(gl, true , true);
+            resetMSAATexture2DSink(gl);
+            
+            if(wasBound) {
+                bind(gl);
+            } else {
+                unbind(gl);
+            }
+            
+            if(DEBUG) {
+                System.err.println("FBObject.reset - END - "+this);
+            }
+        }        
+    }
+            
+    /** 
+     * Note that the status may reflect an incomplete state during transition of attachments.
+     * @return The FB status. {@link GL.GL_FRAMEBUFFER_COMPLETE} if ok, otherwise return GL FBO error state or -1
+     * @see #validateStatus() 
+     */
+    public final int getStatus() {
+        return vStatus;
+    }
+
+    /** return the {@link #getStatus()} as a string. */
+    public final String getStatusString() {
+        return getStatusString(vStatus);
+    }
+    
+    public static final String getStatusString(int fbStatus) {
+        switch(fbStatus) {
+            case -1:
+                return "NOT A FBO";
+                
+            case GL.GL_FRAMEBUFFER_COMPLETE:
+                return "OK";
+                
+            case GL.GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT:
+                return("GL FBO: incomplete, incomplete attachment\n");
+            case GL.GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT:
+                return("GL FBO: incomplete, missing attachment");
+            case GL.GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS:
+                return("GL FBO: incomplete, attached images must have same dimensions");
+            case GL.GL_FRAMEBUFFER_INCOMPLETE_FORMATS:
+                 return("GL FBO: incomplete, attached images must have same format");
+            case GL2GL3.GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER:
+                return("GL FBO: incomplete, missing draw buffer");
+            case GL2GL3.GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER:
+                return("GL FBO: incomplete, missing read buffer");
+            case GL2GL3.GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE:
+                return("GL FBO: incomplete, missing multisample buffer");
+            case GL3.GL_FRAMEBUFFER_INCOMPLETE_LAYER_TARGETS:                
+                return("GL FBO: incomplete, layer targets");
+                
+            case GL.GL_FRAMEBUFFER_UNSUPPORTED:
+                return("GL FBO: Unsupported framebuffer format");
+            case GL2GL3.GL_FRAMEBUFFER_UNDEFINED:
+                 return("GL FBO: framebuffer undefined");
+                 
+            case 0:
+                return("GL FBO: incomplete, implementation fault");
+            default:
+                return("GL FBO: incomplete, implementation ERROR 0x"+Integer.toHexString(fbStatus));
+        }
+    }
+    
+    /**
+     * The status may even be valid if incomplete during transition of attachments.
+     * @see #getStatus()
+     */
+    public final boolean isStatusValid() {
+        switch(vStatus) {
+            case GL.GL_FRAMEBUFFER_COMPLETE:
+                return true;
+                
+            case GL.GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT:
+            case GL.GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT:
+            case GL.GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS:
+            case GL.GL_FRAMEBUFFER_INCOMPLETE_FORMATS:
+            case GL2GL3.GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER:
+            case GL2GL3.GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER:
+            case GL2GL3.GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE:
+            case GL3.GL_FRAMEBUFFER_INCOMPLETE_LAYER_TARGETS:
+                if(0 == colorAttachmentCount || null == depth) {
+                    // we are in transition
+                    return true;
+                }
+         
+            case GL.GL_FRAMEBUFFER_UNSUPPORTED:
+            case GL2GL3.GL_FRAMEBUFFER_UNDEFINED:
+                
+            case 0:                
+            default:
+                System.out.println("Framebuffer " + fbName + " is incomplete: status = 0x" + Integer.toHexString(vStatus) + 
+                        " : " + getStatusString(vStatus));
+                return false;
+        }
+    }
+        
+    private final boolean checkNoError(GL gl, int err, String exceptionMessage) throws GLException {
+        if(GL.GL_NO_ERROR != err) {
+            if(null != gl) {
+                destroy(gl);
+            }
+            if(null != exceptionMessage) {
+                throw new GLException(exceptionMessage+" GL Error 0x"+Integer.toHexString(err));
+            }
+            return false;
+        }
+        return true;
+    }
+
+    private final void checkInitialized() throws GLException {
+        if(!initialized) {
+            throw new GLException("FBO not initialized, call init(GL) first.");
+        }                
+    }
+    
+    /**
+     * Attaches a Texture2D Color Buffer to this FBO's instance at the given attachment point,
+     * selecting the texture data type and format automatically.
+     * 
+     * <p>Using default min/mag filter {@link GL#GL_NEAREST} and default wrapS/wrapT {@link GL#GL_CLAMP_TO_EDGE}.</p>
+     * 
+     * <p>Leaves the FBO bound.</p>
+     * 
+     * @param gl the current GL context
+     * @param attachmentPoint the color attachment point ranging from [0..{@link #getMaxColorAttachments()}-1]
+     * @param alpha set to <code>true</code> if you request alpha channel, otherwise <code>false</code>;
+     * @return TextureAttachment instance describing the new attached texture colorbuffer if bound and configured successfully, otherwise GLException is thrown
+     * @throws GLException in case the texture colorbuffer couldn't be allocated or MSAA has been chosen
+     */
+    public final TextureAttachment attachTexture2D(GL gl, int attachmentPoint, boolean alpha) throws GLException {
+        return attachTexture2D(gl, attachmentPoint, alpha, GL.GL_NEAREST, GL.GL_NEAREST, GL.GL_CLAMP_TO_EDGE, GL.GL_CLAMP_TO_EDGE);
+    }
+    
+    /**
+     * Attaches a Texture2D Color Buffer to this FBO's instance at the given attachment point,
+     * selecting the texture data type and format automatically.
+     * 
+     * <p>Leaves the FBO bound.</p>
+     * 
+     * @param gl the current GL context
+     * @param attachmentPoint the color attachment point ranging from [0..{@link #getMaxColorAttachments()}-1]
+     * @param alpha set to <code>true</code> if you request alpha channel, otherwise <code>false</code>;
+     * @param magFilter if > 0 value for {@link GL#GL_TEXTURE_MAG_FILTER}
+     * @param minFilter if > 0 value for {@link GL#GL_TEXTURE_MIN_FILTER} 
+     * @param wrapS if > 0 value for {@link GL#GL_TEXTURE_WRAP_S}
+     * @param wrapT if > 0 value for {@link GL#GL_TEXTURE_WRAP_T}
+     * @return TextureAttachment instance describing the new attached texture colorbuffer if bound and configured successfully, otherwise GLException is thrown
+     * @throws GLException in case the texture colorbuffer couldn't be allocated or MSAA has been chosen
+     */
+    public final TextureAttachment attachTexture2D(GL gl, int attachmentPoint, boolean alpha, int magFilter, int minFilter, int wrapS, int wrapT) throws GLException {
+        final int textureInternalFormat, textureDataFormat, textureDataType;
+        if(gl.isGLES()) { 
+            textureInternalFormat = alpha ? GL.GL_RGBA : GL.GL_RGB;
+            textureDataFormat = alpha ? GL.GL_RGBA : GL.GL_RGB;
+            textureDataType = GL.GL_UNSIGNED_BYTE;
+        } else { 
+            textureInternalFormat = alpha ? GL.GL_RGBA8 : GL.GL_RGB8;
+            textureDataFormat = alpha ? GL.GL_BGRA : GL.GL_RGB;
+            textureDataType = alpha ? GL2GL3.GL_UNSIGNED_INT_8_8_8_8_REV : GL.GL_UNSIGNED_BYTE;
+        }
+        return attachTexture2D(gl, attachmentPoint, textureInternalFormat, textureDataFormat, textureDataType, magFilter, minFilter, wrapS, wrapT);
+    }
+    
+    /**
+     * Attaches a Texture2D Color Buffer to this FBO's instance at the given attachment point.
+     * 
+     * <p>Leaves the FBO bound.</p>
+     * 
+     * @param gl the current GL context
+     * @param attachmentPoint the color attachment point ranging from [0..{@link #getMaxColorAttachments()}-1]
+     * @param internalFormat internalFormat parameter to {@link GL#glTexImage2D(int, int, int, int, int, int, int, int, long)}
+     * @param dataFormat format parameter to {@link GL#glTexImage2D(int, int, int, int, int, int, int, int, long)}
+     * @param dataType type parameter to {@link GL#glTexImage2D(int, int, int, int, int, int, int, int, long)}
+     * @param magFilter if > 0 value for {@link GL#GL_TEXTURE_MAG_FILTER}
+     * @param minFilter if > 0 value for {@link GL#GL_TEXTURE_MIN_FILTER} 
+     * @param wrapS if > 0 value for {@link GL#GL_TEXTURE_WRAP_S}
+     * @param wrapT if > 0 value for {@link GL#GL_TEXTURE_WRAP_T}
+     * @return TextureAttachment instance describing the new attached texture colorbuffer if bound and configured successfully, otherwise GLException is thrown
+     * @throws GLException in case the texture colorbuffer couldn't be allocated or MSAA has been chosen
+     */
+    public final TextureAttachment attachTexture2D(GL gl, int attachmentPoint,
+                                                   int internalFormat, int dataFormat, int dataType,
+                                                   int magFilter, int minFilter, int wrapS, int wrapT) throws GLException {
+        return attachTexture2D(gl, attachmentPoint, 
+                               new TextureAttachment(Type.COLOR_TEXTURE, internalFormat, width, height, dataFormat, dataType, 
+                                                     magFilter, minFilter, wrapS, wrapT, 0 /* name */));
+    }
+    
+    /**
+     * Attaches a Texture2D Color Buffer to this FBO's instance at the given attachment point.
+     *  
+     * <p>
+     * In case the passed TextureAttachment <code>texA</code> is uninitialized, i.e. it's texture name is <code>zero</code>,
+     * a new texture name is generated and setup w/ the texture parameter.<br/>
+     * Otherwise, i.e. texture name is not <code>zero</code>, the passed TextureAttachment <code>texA</code> is
+     * considered complete and assumed matching this FBO requirement. A GL error may occur is the latter is untrue. 
+     * </p>
+     *    
+     * <p>Leaves the FBO bound.</p>
+     * 
+     * @param gl the current GL context
+     * @param attachmentPoint the color attachment point ranging from [0..{@link #getMaxColorAttachments()}-1]
+     * @param texA the to be attached {@link TextureAttachment}. Maybe complete or uninitialized, see above. 
+     * @return the passed TextureAttachment <code>texA</code> instance describing the new attached texture colorbuffer if bound and configured successfully, otherwise GLException is thrown
+     * @throws GLException in case the texture colorbuffer couldn't be allocated or MSAA has been chosen
+     */
+    public final TextureAttachment attachTexture2D(GL gl, int attachmentPoint, TextureAttachment texA) throws GLException {
+        validateAddColorAttachment(attachmentPoint, texA);
+        
+        if(samples>0) {
+            removeColorAttachment(attachmentPoint, texA);
+            throw new GLException("Texture2D not supported w/ MSAA. If you have enabled MSAA with exisiting texture attachments, you may want to detach them via detachAllTexturebuffer(gl).");
+        }
+        
+        texA.initialize(gl);
+        addColorAttachment(attachmentPoint, texA);
+                
+        bind(gl);
+
+        // Set up the color buffer for use as a renderable texture:
+        gl.glFramebufferTexture2D(GL.GL_FRAMEBUFFER,
+                                  GL.GL_COLOR_ATTACHMENT0 + attachmentPoint,
+                                  GL.GL_TEXTURE_2D, texA.getName(), 0);
+        updateStatus(gl);
+        
+        if(!isStatusValid()) {
+            detachColorbuffer(gl, attachmentPoint);
+            throw new GLException("attachTexture2D "+texA+" at "+attachmentPoint+" failed "+getStatusString()+", "+this);
+        }
+        if(DEBUG) {
+            System.err.println("FBObject.attachTexture2D: "+this);
+        }
+        return texA;
+    }
+    
+    /**
+     * Attaches a Color Buffer to this FBO's instance at the given attachment point,
+     * selecting the format automatically.
+     *  
+     * <p>Leaves the FBO bound.</p>
+     * 
+     * @param gl the current GL context
+     * @param attachmentPoint the color attachment point ranging from [0..{@link #getMaxColorAttachments()}-1]
+     * @param alpha set to <code>true</code> if you request alpha channel, otherwise <code>false</code>;
+     * @return ColorAttachment instance describing the new attached colorbuffer if bound and configured successfully, otherwise GLException is thrown
+     * @throws GLException in case the colorbuffer couldn't be allocated
+     */
+    public final ColorAttachment attachColorbuffer(GL gl, int attachmentPoint, boolean alpha) throws GLException {
+        final int internalFormat;
+        if( rgba8Avail ) {
+            internalFormat = alpha ? GL.GL_RGBA8 : GL.GL_RGB8 ;
+        } else {
+            internalFormat = alpha ? GL.GL_RGBA4 : GL.GL_RGB565;
+        }
+        return attachColorbuffer(gl, attachmentPoint, internalFormat);
+    }
+    
+    /**
+     * Attaches a Color Buffer to this FBO's instance at the given attachment point.
+     *  
+     * <p>Leaves the FBO bound.</p>
+     * 
+     * @param gl the current GL context
+     * @param attachmentPoint the color attachment point ranging from [0..{@link #getMaxColorAttachments()}-1]
+     * @param internalFormat usually {@link GL#GL_RGBA4}, {@link GL#GL_RGB5_A1}, {@link GL#GL_RGB565}, {@link GL#GL_RGB8} or {@link GL#GL_RGBA8}  
+     * @return ColorAttachment instance describing the new attached colorbuffer if bound and configured successfully, otherwise GLException is thrown
+     * @throws GLException in case the colorbuffer couldn't be allocated
+     * @throws IllegalArgumentException if <code>internalFormat</code> doesn't reflect a colorbuffer
+     */
+    public final ColorAttachment attachColorbuffer(GL gl, int attachmentPoint, int internalFormat) throws GLException, IllegalArgumentException {
+        final Attachment.Type atype = Attachment.Type.determine(internalFormat);
+        if( Attachment.Type.COLOR != atype ) {
+            throw new IllegalArgumentException("colorformat invalid: 0x"+Integer.toHexString(internalFormat)+", "+this);
+        }
+        
+        return attachColorbuffer(gl, attachmentPoint, new ColorAttachment(internalFormat, samples, width, height, 0));
+    }
+    
+    /**
+     * Attaches a Color Buffer to this FBO's instance at the given attachment point.
+     *  
+     * <p>Leaves the FBO bound.</p>
+     * 
+     * @param gl
+     * @param attachmentPoint the color attachment point ranging from [0..{@link #getMaxColorAttachments()}-1]
+     * @param colA the template for the new {@link ColorAttachment}   
+     * @return ColorAttachment instance describing the new attached colorbuffer if bound and configured successfully, otherwise GLException is thrown
+     * @throws GLException in case the colorbuffer couldn't be allocated
+     */
+    public final ColorAttachment attachColorbuffer(GL gl, int attachmentPoint, ColorAttachment colA) throws GLException {
+        validateAddColorAttachment(attachmentPoint, colA);
+        
+        colA.initialize(gl);        
+        addColorAttachment(attachmentPoint, colA);
+        
+        bind(gl);
+                
+        // Attach the color buffer
+        gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, 
+                                     GL.GL_COLOR_ATTACHMENT0 + attachmentPoint, 
+                                     GL.GL_RENDERBUFFER, colA.getName());
+
+        updateStatus(gl);                
+        if(!isStatusValid()) {
+            detachColorbuffer(gl, attachmentPoint);
+            throw new GLException("attachColorbuffer "+colA+" at "+attachmentPoint+" failed "+getStatusString()+", "+this);
+        }
+        if(DEBUG) {
+            System.err.println("FBObject.attachColorbuffer: "+this);
+        }
+        return colA;
+    }
+
+    
+    /**
+     * Attaches one depth, stencil or packed-depth-stencil buffer to this FBO's instance,
+     * selecting the internalFormat automatically.
+     * <p>
+     * Stencil and depth buffer can be attached only once.
+     * </p>
+     * <p>
+     * In case the desired type or bit-number is not supported, the next available one is chosen.
+     * </p>  
+     * <p>
+     * Use {@link #getDepthAttachment()} and/or {@link #getStencilAttachment()} to retrieve details
+     * about the attached buffer. The details cannot be returned, since it's possible 2 buffers
+     * are being created, depth and stencil.
+     * </p>
+     * 
+     * <p>Leaves the FBO bound.</p>
+     * 
+     * @param gl
+     * @param atype either {@link Type#DEPTH}, {@link Type#STENCIL} or {@link Type#DEPTH_STENCIL}  
+     * @param reqBits desired bits for depth or -1 for default (24 bits)
+     * @throws GLException in case the renderbuffer couldn't be allocated or one is already attached.
+     * @throws IllegalArgumentException
+     * @see #getDepthAttachment()
+     * @see #getStencilAttachment()
+     */
+    public final void attachRenderbuffer(GL gl, Attachment.Type atype, int reqBits) throws GLException, IllegalArgumentException {        
+        if( 0 > reqBits ) {
+            reqBits = 24;
+        }        
+        final int internalFormat;
+        int internalStencilFormat = -1;
+        
+        switch ( atype ) {
+            case DEPTH:
+                if( 32 <= reqBits && depth32Avail ) {
+                    internalFormat = GL.GL_DEPTH_COMPONENT32;
+                } else if( 24 <= reqBits && depth24Avail ) {
+                    internalFormat = GL.GL_DEPTH_COMPONENT24;
+                } else {
+                    internalFormat = GL.GL_DEPTH_COMPONENT16;                    
+                }
+                break;
+                
+            case STENCIL:
+                if( 16 <= reqBits && stencil16Avail ) {
+                    internalFormat = GL2GL3.GL_STENCIL_INDEX16;
+                } else if( 8 <= reqBits && stencil08Avail ) {
+                    internalFormat = GL.GL_STENCIL_INDEX8;
+                } else if( 4 <= reqBits && stencil04Avail ) {
+                    internalFormat = GL.GL_STENCIL_INDEX4;
+                } else if( 1 <= reqBits && stencil01Avail ) {
+                    internalFormat = GL.GL_STENCIL_INDEX1;
+                } else {
+                    throw new GLException("stencil buffer n/a");        
+                }
+                break;
+                
+            case DEPTH_STENCIL:
+                if( packedDepthStencilAvail ) {
+                    internalFormat = GL.GL_DEPTH24_STENCIL8;
+                } else {
+                    if( 24 <= reqBits && depth24Avail ) {
+                        internalFormat = GL.GL_DEPTH_COMPONENT24;
+                    } else {
+                        internalFormat = GL.GL_DEPTH_COMPONENT16;                    
+                    }
+                    if( stencil08Avail ) {
+                        internalStencilFormat = GL.GL_STENCIL_INDEX8;
+                    } else if( stencil04Avail ) {
+                        internalStencilFormat = GL.GL_STENCIL_INDEX4;
+                    } else if( stencil01Avail ) {
+                        internalStencilFormat = GL.GL_STENCIL_INDEX1;
+                    } else {
+                        throw new GLException("stencil buffer n/a");
+                    }
+                }
+                break;
+            default:
+                throw new IllegalArgumentException("only depth/stencil types allowed, was "+atype+", "+this);
+        }
+        
+        attachRenderbufferImpl(gl, atype, internalFormat);
+        
+        if(0<=internalStencilFormat) {
+            attachRenderbufferImpl(gl, Attachment.Type.STENCIL, internalStencilFormat);
+        }
+    }
+    
+    /**
+     * Attaches one depth, stencil or packed-depth-stencil buffer to this FBO's instance,
+     * depending on the <code>internalFormat</code>. 
+     * <p>
+     * Stencil and depth buffer can be attached only once.
+     * </p>
+     * <p>
+     * Use {@link #getDepthAttachment()} and/or {@link #getStencilAttachment()} to retrieve details
+     * about the attached buffer. The details cannot be returned, since it's possible 2 buffers
+     * are being created, depth and stencil.
+     * </p>
+     * 
+     * <p>Leaves the FBO bound.</p>
+     * 
+     * @param gl the current GL context
+     * @param internalFormat {@link GL#GL_DEPTH_COMPONENT16}, {@link GL#GL_DEPTH_COMPONENT24}, {@link GL#GL_DEPTH_COMPONENT32},
+     *                       {@link GL#GL_STENCIL_INDEX1}, {@link GL#GL_STENCIL_INDEX4}, {@link GL#GL_STENCIL_INDEX8}
+     *                       or {@link GL#GL_DEPTH24_STENCIL8}
+     * @throws GLException in case the renderbuffer couldn't be allocated or one is already attached.
+     * @throws IllegalArgumentException
+     * @see #getDepthAttachment()
+     * @see #getStencilAttachment()
+     */
+    public final void attachRenderbuffer(GL gl, int internalFormat) throws GLException, IllegalArgumentException {
+        final Attachment.Type atype = Attachment.Type.determine(internalFormat);
+        if( Attachment.Type.DEPTH != atype && Attachment.Type.STENCIL != atype && Attachment.Type.DEPTH_STENCIL != atype ) {
+            throw new IllegalArgumentException("renderformat invalid: 0x"+Integer.toHexString(internalFormat)+", "+this);
+        }
+        attachRenderbufferImpl(gl, atype, internalFormat);
+    }
+    
+    protected final void attachRenderbufferImpl(GL gl, Attachment.Type atype, int internalFormat) throws GLException {
+        if( null != depth && ( Attachment.Type.DEPTH == atype || Attachment.Type.DEPTH_STENCIL == atype ) ) {
+            throw new GLException("FBO depth buffer already attached (rb "+depth+"), type is "+atype+", 0x"+Integer.toHexString(internalFormat)+", "+this);
+        }        
+        if( null != stencil && ( Attachment.Type.STENCIL== atype || Attachment.Type.DEPTH_STENCIL == atype ) ) {
+            throw new GLException("FBO stencil buffer already attached (rb "+stencil+"), type is "+atype+", 0x"+Integer.toHexString(internalFormat)+", "+this);
+        }
+        attachRenderbufferImpl2(gl, atype, internalFormat);
+    }
+        
+    private final void attachRenderbufferImpl2(GL gl, Attachment.Type atype, int internalFormat) throws GLException {
+        if( Attachment.Type.DEPTH == atype ) {
+            if(null == depth) {
+                depth = new RenderAttachment(Type.DEPTH, internalFormat, samples, width, height, 0);
+            } else {
+                depth.setSize(width, height);
+                depth.setSamples(samples);
+            }
+            depth.initialize(gl);
+        } else if( Attachment.Type.STENCIL == atype ) {
+            if(null == stencil) {
+                stencil = new RenderAttachment(Type.STENCIL, internalFormat, samples, width, height, 0);
+            } else {
+                stencil.setSize(width, height);
+                stencil.setSamples(samples);
+            }
+            stencil.initialize(gl);
+        } else if( Attachment.Type.DEPTH_STENCIL == atype ) {
+            if(null == depth) {
+                depth = new RenderAttachment(Type.DEPTH, internalFormat, samples, width, height, 0);
+            } else {
+                depth.setSize(width, height);
+                depth.setSamples(samples);
+            }
+            depth.initialize(gl);
+            if(null == stencil) {
+                stencil = new RenderAttachment(Type.STENCIL, internalFormat, samples, width, height, depth.getName());
+            } else {
+                stencil.setName(depth.getName());
+                stencil.setSize(width, height);
+                stencil.setSamples(samples);
+            }
+            stencil.initialize(gl);
+        }
+
+        bind(gl);
+        
+        // Attach the buffer
+        if( Attachment.Type.DEPTH == atype ) {
+            gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, GL.GL_DEPTH_ATTACHMENT, GL.GL_RENDERBUFFER, depth.getName());
+        } else if( Attachment.Type.STENCIL == atype ) {
+            gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, GL.GL_STENCIL_ATTACHMENT, GL.GL_RENDERBUFFER, stencil.getName());
+        } else if( Attachment.Type.DEPTH_STENCIL == atype ) {
+            gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, GL.GL_DEPTH_ATTACHMENT, GL.GL_RENDERBUFFER, depth.getName());            
+            gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, GL.GL_STENCIL_ATTACHMENT, GL.GL_RENDERBUFFER, stencil.getName());
+        }
+        
+        updateStatus(gl);
+        if( !isStatusValid() ) {
+            detachRenderbuffer(gl, atype);
+            throw new GLException("renderbuffer attachment failed: "+this.getStatusString());
+        }
+
+        if(DEBUG) {
+            System.err.println("FBObject.attachRenderbuffer: "+this);
+        }
+    }
+    
+    /**
+     * <p>Leaves the FBO bound!</p>
+     * @param gl
+     * @param ca
+     * @throws IllegalArgumentException
+     */
+    public final void detachColorbuffer(GL gl, int attachmentPoint) throws IllegalArgumentException {
+        if(null == detachColorbufferImpl(gl, attachmentPoint, false)) {
+            throw new IllegalArgumentException("ColorAttachment at "+attachmentPoint+", not attached, "+this);            
+        }
+        if(DEBUG) {
+            System.err.println("FBObject.detachAll: "+this);
+        }
+    }
+    
+    private final Colorbuffer detachColorbufferImpl(GL gl, int attachmentPoint, boolean recreate) {
+        final Colorbuffer colbuf = colorAttachmentPoints[attachmentPoint]; // shortcut, don't validate here
+        
+        if(null == colbuf) {
+            return null;
+        }
+        
+        bind(gl);
+        
+        if(colbuf instanceof TextureAttachment) {
+            final TextureAttachment texA = (TextureAttachment) colbuf;
+            if( 0 != texA.getName() ) {
+                gl.glFramebufferTexture2D(GL.GL_FRAMEBUFFER,
+                              GL.GL_COLOR_ATTACHMENT0 + attachmentPoint,
+                              GL.GL_TEXTURE_2D, 0, 0);
+                gl.glBindTexture(GL.GL_TEXTURE_2D, 0);
+            }
+            texA.free(gl);
+            removeColorAttachment(attachmentPoint, texA);                
+            if(recreate) {
+                texA.setSize(width, height);
+                attachTexture2D(gl, attachmentPoint, texA);
+            }
+        } else if(colbuf instanceof ColorAttachment) {
+            final ColorAttachment colA = (ColorAttachment) colbuf;
+            if( 0 != colA.getName() ) {
+                gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, 
+                                             GL.GL_COLOR_ATTACHMENT0+attachmentPoint, 
+                                             GL.GL_RENDERBUFFER, 0);
+            }
+            colA.free(gl);
+            removeColorAttachment(attachmentPoint, colbuf);
+            if(recreate) {
+                colA.setSize(width, height);
+                colA.setSamples(samples);
+                attachColorbuffer(gl, attachmentPoint, colA);
+            }
+        }
+        return colbuf;
+    }
+    
+    /**
+     * 
+     * @param gl
+     * @param reqAType {@link Type#DEPTH}, {@link Type#DEPTH} or {@link Type#DEPTH_STENCIL} 
+     */
+    public final void detachRenderbuffer(GL gl, Attachment.Type atype) throws IllegalArgumentException {
+        detachRenderbufferImpl(gl, atype, false);
+    }
+    
+    public final boolean isDepthStencilPackedFormat() {
+        final boolean res = null != depth && null != stencil &&
+                            depth.format == stencil.format ;
+        if(res && depth.getName() != stencil.getName() ) {
+            throw new InternalError("depth/stencil packed format not sharing: depth "+depth+", stencil "+stencil);
+        }
+        return res;
+    }
+        
+    private final void detachRenderbufferImpl(GL gl, Attachment.Type atype, boolean recreate) throws IllegalArgumentException {
+        switch ( atype ) {
+            case DEPTH:
+            case STENCIL:
+            case DEPTH_STENCIL:             
+             break;
+             default:
+                 throw new IllegalArgumentException("only depth/stencil types allowed, was "+atype+", "+this);
+        }        
+        if( null == depth && null == stencil ) {
+            return ; // nop
+        } 
+        // reduction of possible combinations, create unique atype command(s)
+        final ArrayList<Attachment.Type> actions = new ArrayList<Attachment.Type>(2);  
+        if( isDepthStencilPackedFormat() ) {
+            // packed
+            actions.add(Attachment.Type.DEPTH_STENCIL);
+        } else {
+            // individual
+            switch ( atype ) {
+                case DEPTH:
+                    if( null != depth ) { actions.add(Attachment.Type.DEPTH); }
+                    break;
+                case STENCIL:
+                    if( null != stencil ) { actions.add(Attachment.Type.STENCIL); }
+                    break;
+                case DEPTH_STENCIL:
+                    if( null != depth ) { actions.add(Attachment.Type.DEPTH); }
+                    if( null != stencil ) { actions.add(Attachment.Type.STENCIL); }
+                    break;
+                 default: // handled
+            }
+        }
+        
+        bind(gl);        
+        
+        for(int i = 0; i < actions.size(); i++) {
+            final int format;
+            
+            Attachment.Type action = actions.get(i);
+            switch ( action ) {
+                case DEPTH:
+                    format = depth.format;
+                    if( 0 != depth.getName() ) {
+                        gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, GL.GL_DEPTH_ATTACHMENT, GL.GL_RENDERBUFFER, 0);
+                    }
+                    depth.free(gl);
+                    if(!recreate) {
+                        depth = null;
+                    }
+                    break;
+                case STENCIL:
+                    format = stencil.format;
+                    if(0 != stencil.getName()) {
+                        gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, GL.GL_STENCIL_ATTACHMENT, GL.GL_RENDERBUFFER, 0);
+                    }
+                    stencil.free(gl);
+                    if(!recreate) {
+                        stencil = null;
+                    }
+                    break;
+                case DEPTH_STENCIL:
+                    format = depth.format;
+                    if(0 != depth.getName()) {
+                        gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, GL.GL_DEPTH_ATTACHMENT, GL.GL_RENDERBUFFER, 0);
+                        gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER, GL.GL_STENCIL_ATTACHMENT, GL.GL_RENDERBUFFER, 0);
+                    }
+                    depth.free(gl);
+                    stencil.free(gl);
+                    if(!recreate) {
+                        depth = null;
+                        stencil = null;
+                    }
+                    break;
+                 default:
+                    throw new InternalError("XXX");
+            }
+            if(recreate) {
+                attachRenderbufferImpl2(gl, action, format);
+            }
+        }        
+    }
+        
+    /** 
+     * Detaches all {@link ColorAttachment}s, {@link TextureAttachment}s and {@link RenderAttachment}s.
+     * <p>Leaves the FBO bound!</p>
+     * <p>
+     * An attached sampling sink texture will be detached as well, see {@link #getSamplingSink()}.
+     * </p> 
+     * @param gl the current GL context
+     */
+    public final void detachAll(GL gl) {
+        if(null != samplesSink) {
+            samplesSink.detachAll(gl);
+        }        
+        detachAllImpl(gl, true/* detachNonColorbuffer */, false /* recreate */);
+    }
+    
+    /** 
+     * Detaches all {@link ColorAttachment}s and {@link TextureAttachment}s.
+     * <p>Leaves the FBO bound!</p>
+     * <p>
+     * An attached sampling sink texture will be detached as well, see {@link #getSamplingSink()}.
+     * </p> 
+     * @param gl the current GL context
+     */
+    public final void detachAllColorbuffer(GL gl) {
+        if(null != samplesSink) {
+            samplesSink.detachAllColorbuffer(gl);
+        }        
+        detachAllImpl(gl, false/* detachNonColorbuffer */, false /* recreate */);
+    }
+    
+    /** 
+     * Detaches all {@link TextureAttachment}s 
+     * <p>Leaves the FBO bound!</p>
+     * <p>
+     * An attached sampling sink texture will be detached as well, see {@link #getSamplingSink()}.
+     * </p> 
+     * @param gl the current GL context
+     */
+    public final void detachAllTexturebuffer(GL gl) {
+        if(null != samplesSink) {
+            samplesSink.detachAllTexturebuffer(gl);
+        }
+        for(int i=0; i<maxColorAttachments; i++) {
+            if(colorAttachmentPoints[i] instanceof TextureAttachment) {
+                detachColorbufferImpl(gl, i, false);
+            }
+        }
+    }
+    
+    public final void detachAllRenderbuffer(GL gl) {
+        if(null != samplesSink) {
+            samplesSink.detachAllRenderbuffer(gl);
+        }
+        detachRenderbufferImpl(gl, Attachment.Type.DEPTH_STENCIL, false);
+    }
+    
+    private final void detachAllImpl(GL gl, boolean detachNonColorbuffer, boolean recreate) {
+        for(int i=0; i<maxColorAttachments; i++) {
+            detachColorbufferImpl(gl, i, recreate);
+        }
+        if( !recreate && colorAttachmentCount>0 ) {
+            throw new InternalError("Non zero ColorAttachments "+this);
+        }
+        
+        if(detachNonColorbuffer) {
+            detachRenderbufferImpl(gl, Attachment.Type.DEPTH_STENCIL, recreate);
+        }
+        
+        if(DEBUG) {
+            System.err.println("FBObject.detachAll: [resetNonColorbuffer "+detachNonColorbuffer+", recreate "+recreate+"]: "+this);
+        }
+    }
+        
+    /**
+     * @param gl the current GL context
+     */
+    public final void destroy(GL gl) {
+        if(null != samplesSink) {
+            samplesSink.destroy(gl);
+        }
+        
+        detachAllImpl(gl, true /* detachNonColorbuffer */, false /* recreate */);
+        
+        // cache FB names, preset exposed to zero,
+        // braking ties w/ GL/GLContext link to getReadFramebuffer()/getWriteFramebuffer()
+        final int fb_cache = fbName;
+        fbName = 0;
+
+        int name[] = new int[1];
+        if(0!=fb_cache) {
+            name[0] = fb_cache;
+            gl.glDeleteFramebuffers(1, name, 0);
+        }        
+        initialized = false;
+        bound = false;
+        if(DEBUG) {
+            System.err.println("FBObject.destroy: "+this);
+        }
+    }
+
+    private final boolean sampleSinkSizeMismatch() {
+        return samplesSink.getWidth() != width || samplesSink.getHeight() != height ;
+    }
+    private final boolean sampleSinkTexMismatch() {
+        return null == samplesSinkTexture || 0 == samplesSinkTexture.getName() ;
+    }
+    private final boolean sampleSinkDepthStencilMismatch() {
+        final boolean depthMismatch   = ( null != depth && null == samplesSink.depth ) ||
+                                        ( null != depth && null != samplesSink.depth &&
+                                          depth.format != samplesSink.depth.format );
+        
+        final boolean stencilMismatch = ( null != stencil && null == samplesSink.stencil ) ||
+                                        ( null != stencil && null != samplesSink.stencil &&
+                                          stencil.format != samplesSink.stencil.format );        
+        
+        return depthMismatch || stencilMismatch;                
+    }
+        
+    private final void resetMSAATexture2DSink(GL gl) throws GLException {
+        if(0 == samples) {
+            // MSAA off
+            if(null != samplesSink) {
+                samplesSink.detachAll(gl);
+            }
+            return;
+        }
+        
+        boolean sampleSinkSizeMismatch = sampleSinkSizeMismatch();
+        boolean sampleSinkTexMismatch = sampleSinkTexMismatch();
+        boolean sampleSinkDepthStencilMismatch = sampleSinkDepthStencilMismatch();
+        
+        /** if(DEBUG) {
+            System.err.println("FBObject.resetMSAATexture2DSink.0: \n\tTHIS "+this+",\n\tSINK "+samplesSink+
+                               "\n\t size "+sampleSinkSizeMismatch +", tex "+sampleSinkTexMismatch +", depthStencil "+sampleSinkDepthStencilMismatch);
+        } */
+        
+        if(!sampleSinkSizeMismatch && !sampleSinkTexMismatch && !sampleSinkDepthStencilMismatch) {
+            // all properties match .. 
+            return;            
+        }
+        
+        unbind(gl);
+        
+        if(DEBUG) {
+            System.err.println("FBObject.resetMSAATexture2DSink: BEGIN\n\tTHIS "+this+",\n\tSINK "+samplesSink+
+                               "\n\t size "+sampleSinkSizeMismatch +", tex "+sampleSinkTexMismatch +", depthStencil "+sampleSinkDepthStencilMismatch);
+        }
+                
+        if( sampleSinkDepthStencilMismatch ) {
+            samplesSink.detachAllRenderbuffer(gl);
+        }
+        
+        if( sampleSinkSizeMismatch ) {
+            samplesSink.reset(gl, width, height);
+        }
+        
+        if(null == samplesSinkTexture) {
+            samplesSinkTexture = samplesSink.attachTexture2D(gl, 0, true);
+        } else if( 0 == samplesSinkTexture.getName() ) {
+            samplesSinkTexture.setSize(width, height);
+            samplesSink.attachTexture2D(gl, 0, samplesSinkTexture);
+        }
+        
+        if( sampleSinkDepthStencilMismatch ) {
+            samplesSink.attachRenderbuffer(gl, depth.format);
+            if( null != stencil && !isDepthStencilPackedFormat() ) {
+                samplesSink.attachRenderbuffer(gl, stencil.format);
+            }
+        }        
+        
+        sampleSinkSizeMismatch = sampleSinkSizeMismatch();
+        sampleSinkTexMismatch = sampleSinkTexMismatch();
+        sampleSinkDepthStencilMismatch = sampleSinkDepthStencilMismatch();
+        if(sampleSinkSizeMismatch || sampleSinkTexMismatch || sampleSinkDepthStencilMismatch) {
+            throw new InternalError("Samples sink mismatch after reset: \n\tTHIS "+this+",\n\t SINK "+samplesSink+
+                                    "\n\t size "+sampleSinkSizeMismatch +", tex "+sampleSinkTexMismatch +", depthStencil "+sampleSinkDepthStencilMismatch);
+        }
+        
+        if(DEBUG) {
+            System.err.println("FBObject.resetMSAATexture2DSink: END\n\tTHIS "+this+",\n\tSINK "+samplesSink+
+                               "\n\t size "+sampleSinkSizeMismatch +", tex "+sampleSinkTexMismatch +", depthStencil "+sampleSinkDepthStencilMismatch);
+        }
+    }
+    
+    /** 
+     * Bind this FBO, i.e. bind write framebuffer to {@link #getWriteFramebuffer()}.
+     * 
+     * <p>If multisampling is used, it sets the read framebuffer to the sampling sink {@link #getWriteFramebuffer()}, 
+     * if full FBO is supported.</p>
+     *  
+     * <p> 
+     * In case you have attached more than one color buffer,
+     * you may want to setup {@link GL2GL3#glDrawBuffers(int, int[], int)}.
+     * </p>
+     * @param gl the current GL context
+     * @throws GLException
+     */
+    public final void bind(GL gl) throws GLException {
+        if(!bound || fbName != gl.getBoundFramebuffer(GL.GL_FRAMEBUFFER)) {
+            checkInitialized();
+            if(samples > 0 && fullFBOSupport) {
+                // draw to multisampling - read from samplesSink
+                gl.glBindFramebuffer(GL2GL3.GL_DRAW_FRAMEBUFFER, getWriteFramebuffer());
+                gl.glBindFramebuffer(GL2GL3.GL_READ_FRAMEBUFFER, getReadFramebuffer());
+            } else {
+                // one for all
+                gl.glBindFramebuffer(GL.GL_FRAMEBUFFER, getWriteFramebuffer());                
+            }
+
+            checkNoError(null, gl.glGetError(), "FBObject post-bind"); // throws GLException if error
+            bound = true;
+            samplesSinkDirty = true;
+        }
+    }
+
+    /** 
+     * Unbind this FBO, i.e. bind read and write framebuffer to default, see {@link GLBase#getDefaultDrawFramebuffer()}.
+     * 
+     * <p>If full FBO is supported, sets the read and write framebuffer individually to default, hence not disturbing 
+     * an optional operating MSAA FBO, see {@link GLBase#getDefaultReadFramebuffer()} and {@link GLBase#getDefaultDrawFramebuffer()}</p>
+     *  
+     * @param gl the current GL context
+     * @throws GLException
+     */
+    public final void unbind(GL gl) throws GLException {
+        if(bound) {
+            if(fullFBOSupport) {
+                // default read/draw buffers, may utilize GLContext/GLDrawable override of 
+                // GLContext.getDefaultDrawFramebuffer() and GLContext.getDefaultReadFramebuffer()
+                gl.glBindFramebuffer(GL2GL3.GL_DRAW_FRAMEBUFFER, 0);
+                gl.glBindFramebuffer(GL2GL3.GL_READ_FRAMEBUFFER, 0);
+            } else {
+                gl.glBindFramebuffer(GL.GL_FRAMEBUFFER, 0); // default draw buffer                
+            }
+            checkNoError(null, gl.glGetError(), "FBObject post-unbind"); // throws GLException if error
+            bound = false;
+        }
+    }
+
+    /** 
+     * Returns <code>true</code> if framebuffer object is bound via {@link #bind(GL)}, otherwise <code>false</code>.
+     * <p>
+     * Method verifies the bound state via {@link GL#getBoundFramebuffer(int)}.
+     * </p>
+     * @param gl the current GL context
+     */
+    public final boolean isBound(GL gl) { 
+        bound = bound &&  fbName != gl.getBoundFramebuffer(GL.GL_FRAMEBUFFER) ;
+        return bound;
+    }
+    
+    /** Returns <code>true</code> if framebuffer object is bound via {@link #bind(GL)}, otherwise <code>false</code>. */
+    public final boolean isBound() { return bound; }
+    
+    /** 
+     * Samples the multisampling colorbuffer (msaa-buffer) to it's sink {@link #getSamplingSink()}.
+     *
+     * <p>The operation is skipped, if no multisampling is used or 
+     * the msaa-buffer has not been flagged dirty by a previous call of {@link #bind(GL)},
+     * see {@link #isSamplingBufferDirty()} </p>
+     * 
+     * <p>If full FBO is supported, sets the read and write framebuffer individually to default after sampling, hence not disturbing 
+     * an optional operating MSAA FBO, see {@link GLBase#getDefaultReadFramebuffer()} and {@link GLBase#getDefaultDrawFramebuffer()}</p>
+     * 
+     * <p>In case you intend to employ {@link GL#glReadPixels(int, int, int, int, int, int, java.nio.Buffer) glReadPixels(..)}
+     * you may want to call {@link GL#glBindFramebuffer(int, int) glBindFramebuffer}({@link GL2GL3#GL_READ_FRAMEBUFFER}, {@link #getReadFramebuffer()});
+     * </p>
+     * 
+     * <p>Leaves the FBO unbound.</p>
+     * 
+     * @param gl the current GL context
+     * @param ta {@link TextureAttachment} to use, prev. attached w/  {@link #attachTexture2D(GL, int, boolean, int, int, int, int) attachTexture2D(..)}
+     * @throws IllegalArgumentException  
+     */
+    public final void syncSamplingBuffer(GL gl) {
+        unbind(gl);
+        if(samples>0 && samplesSinkDirty) {
+            samplesSinkDirty = false;
+            resetMSAATexture2DSink(gl);
+            gl.glBindFramebuffer(GL2GL3.GL_READ_FRAMEBUFFER, fbName);
+            gl.glBindFramebuffer(GL2GL3.GL_DRAW_FRAMEBUFFER, samplesSink.getWriteFramebuffer());
+            ((GL2GL3)gl).glBlitFramebuffer(0, 0, width, height, 0, 0, width, height, // since MSAA is supported, ugly cast is OK
+                                           GL.GL_COLOR_BUFFER_BIT, GL.GL_NEAREST);
+            if(fullFBOSupport) {
+                // default read/draw buffers, may utilize GLContext/GLDrawable override of 
+                // GLContext.getDefaultDrawFramebuffer() and GLContext.getDefaultReadFramebuffer()
+                gl.glBindFramebuffer(GL2GL3.GL_DRAW_FRAMEBUFFER, 0);
+                gl.glBindFramebuffer(GL2GL3.GL_READ_FRAMEBUFFER, 0);
+            } else {
+                gl.glBindFramebuffer(GL.GL_FRAMEBUFFER, 0); // default draw buffer                
+            }
+        }
+    }
+    
+    /** 
+     * Bind the given texture colorbuffer.
+     * 
+     * <p>If multisampling is being used, {@link #syncSamplingBuffer(GL)} is being called.</p>
+     *  
+     * <p>Leaves the FBO unbound!</p>
+     * 
+     * @param gl the current GL context
+     * @param ta {@link TextureAttachment} to use, prev. attached w/  {@link #attachTexture2D(GL, int, boolean, int, int, int, int) attachTexture2D(..)}
+     * @throws IllegalArgumentException  
+     */
+    public final void use(GL gl, TextureAttachment ta) throws IllegalArgumentException {
+        if(null == ta) { throw new IllegalArgumentException("null TextureAttachment"); }
+        if(samples > 0 && samplesSinkTexture == ta) {
+            syncSamplingBuffer(gl);
+        } else {
+            unbind(gl);            
+        }
+        gl.glBindTexture(GL.GL_TEXTURE_2D, ta.getName()); // use it ..
+    }
+
+    /** 
+     * Unbind texture, ie bind 'non' texture 0
+     *  
+     * <p>Leaves the FBO unbound.</p>
+     */    
+    public final void unuse(GL gl) {
+        unbind(gl);
+        gl.glBindTexture(GL.GL_TEXTURE_2D, 0); // don't use it
+    }
+
+    /** 
+     * Returns <code>true</code> if <i>basic</i> or <i>full</i> FBO is supported, otherwise <code>false</code>.
+     * @param full <code>true</code> for <i>full</i> FBO supported query, otherwise <code>false</code> for <i>basic</i> FBO support query.
+     * @see #supportsFullFBO(GL)
+     * @see #supportsBasicFBO(GL)
+     * @throws GLException if {@link #init(GL)} hasn't been called.
+     */
+    public final boolean supportsFBO(boolean full) throws GLException { checkInitialized(); return full ? fullFBOSupport : basicFBOSupport; }
+    
+    /** 
+     * Returns <code>true</code> if renderbuffer accepts internal format {@link GL#GL_RGB8} and {@link GL#GL_RGBA8}, otherwise <code>false</code>.
+     * @throws GLException if {@link #init(GL)} hasn't been called.
+     */
+    public final boolean supportsRGBA8() throws GLException { checkInitialized(); return rgba8Avail; }
+    
+    /** 
+     * Returns <code>true</code> if {@link GL#GL_DEPTH_COMPONENT16}, {@link GL#GL_DEPTH_COMPONENT24} or {@link GL#GL_DEPTH_COMPONENT32} is supported, otherwise <code>false</code>.
+     * @param bits 16, 24 or 32 bits
+     * @throws GLException if {@link #init(GL)} hasn't been called.
+     */
+    public final boolean supportsDepth(int bits) throws GLException {
+        checkInitialized();
+        switch(bits) {
+            case 16: return basicFBOSupport; 
+            case 24: return depth24Avail;
+            case 32: return depth32Avail;
+            default: return false;            
+        }
+    }
+    
+    /** 
+     * Returns <code>true</code> if {@link GL#GL_STENCIL_INDEX1}, {@link GL#GL_STENCIL_INDEX4}, {@link GL#GL_STENCIL_INDEX8} or {@link GL2GL3#GL_STENCIL_INDEX16} is supported, otherwise <code>false</code>.
+     * @param bits 1, 4, 8 or 16 bits
+     * @throws GLException if {@link #init(GL)} hasn't been called.
+     */
+    public final boolean supportsStencil(int bits) throws GLException {
+        checkInitialized();
+        switch(bits) {
+            case  1: return stencil01Avail; 
+            case  4: return stencil04Avail;
+            case  8: return stencil08Avail;
+            case 16: return stencil16Avail;
+            default: return false;            
+        }
+    }
+    
+    /** 
+     * Returns <code>true</code> if {@link GL#GL_DEPTH24_STENCIL8} is supported, otherwise <code>false</code>.
+     * @throws GLException if {@link #init(GL)} hasn't been called.
+     */
+    public final boolean supportsPackedDepthStencil() throws GLException { checkInitialized(); return packedDepthStencilAvail; }
+    
+    /**
+     * Returns the maximum number of colorbuffer attachments.
+     * @throws GLException if {@link #init(GL)} hasn't been called.
+     */
+    public final int getMaxColorAttachments() throws GLException { checkInitialized(); return maxColorAttachments; }
+    
+    /**
+     * Returns the maximum number of samples for multisampling. Maybe zero if multisampling is not supported. 
+     * @throws GLException if {@link #init(GL)} hasn't been called.
+     */
+    public final int getMaxSamples() throws GLException { checkInitialized(); return maxSamples; }
+    
+    /**
+     * Returns <code>true</code> if this instance has been initialized with {@link #reset(GL, int, int)} 
+     * or {@link #reset(GL, int, int, int)}, otherwise <code>false</code>
+     */
+    public final boolean isInitialized() { return initialized; }
+    /** Returns the width */
+    public final int getWidth() { return width; }
+    /** Returns the height */
+    public final int getHeight() { return height; }
+    /** Returns the number of samples for multisampling (MSAA). zero if no multisampling is used. */
+    public final int getNumSamples() { return samples; }
+    /** Returns the framebuffer name to render to. */
+    public final int getWriteFramebuffer() { return fbName; }
+    /** Returns the framebuffer name to read from. Depending on multisampling, this may be a different framebuffer. */
+    public final int getReadFramebuffer() { return ( samples > 0 ) ? samplesSink.getReadFramebuffer() : fbName; }
+    /** Return the number of color/texture attachments */
+    public final int getColorAttachmentCount() { return colorAttachmentCount; }
+    /** Return the stencil {@link RenderAttachment} attachment, if exist. Maybe share the same {@link Attachment#getName()} as {@link #getDepthAttachment()}, if packed depth-stencil is being used. */ 
+    public final RenderAttachment getStencilAttachment() { return stencil; }
+    /** Return the depth {@link RenderAttachment} attachment. Maybe share the same {@link Attachment#getName()} as {@link #getStencilAttachment()}, if packed depth-stencil is being used. */ 
+    public final RenderAttachment getDepthAttachment() { return depth; }
+    
+    /** Return the complete multisampling {@link FBObject} sink, if using multisampling. */ 
+    public final FBObject getSamplingSinkFBO() { return samplesSink; }
+    
+    /** Return the multisampling {@link TextureAttachment} sink, if using multisampling. */ 
+    public final TextureAttachment getSamplingSink() { return samplesSinkTexture; }
+    /** 
+     * Returns <code>true</code> if the multisampling colorbuffer (msaa-buffer) 
+     * has been flagged dirty by a previous call of {@link #bind(GL)},
+     * otherwise <code>false</code>.
+     */
+    public final boolean isSamplingBufferDirty() { return samplesSinkDirty; }
+    
+    int objectHashCode() { return super.hashCode(); }
+    
+    public final String toString() {
+        final String caps = null != colorAttachmentPoints ? Arrays.asList(colorAttachmentPoints).toString() : null ; 
+        return "FBO[name r/w "+fbName+"/"+getReadFramebuffer()+", init "+initialized+", bound "+bound+", size "+width+"x"+height+", samples "+samples+"/"+maxSamples+
+               ", depth "+depth+", stencil "+stencil+", color attachments: "+colorAttachmentCount+"/"+maxColorAttachments+
+               ": "+caps+", msaa-sink "+samplesSinkTexture+", isSamplesSink "+(null == samplesSink)+
+               ", obj 0x"+Integer.toHexString(objectHashCode())+"]";
+    }
+    
+    private final void updateStatus(GL gl) {
+        if( 0 == fbName ) {
+            vStatus = -1;
+        } else {
+            vStatus = gl.glCheckFramebufferStatus(GL.GL_FRAMEBUFFER);
+        }
+    }       
+}
diff --git a/src/jogl/classes/com/jogamp/opengl/GLExtensions.java b/src/jogl/classes/com/jogamp/opengl/GLExtensions.java
new file mode 100644
index 000000000..f7e25fa01
--- /dev/null
+++ b/src/jogl/classes/com/jogamp/opengl/GLExtensions.java
@@ -0,0 +1,81 @@
+/**
+ * Copyright 2012 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ *
+ *    1. Redistributions of source code must retain the above copyright notice, this list of
+ *       conditions and the following disclaimer.
+ *
+ *    2. Redistributions in binary form must reproduce the above copyright notice, this list
+ *       of conditions and the following disclaimer in the documentation and/or other materials
+ *       provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
+package com.jogamp.opengl;
+
+/**
+ * Class holding OpenGL extension strings, commonly used by JOGL's implementation. 
+ */
+public class GLExtensions {
+  public static final String VERSION_1_2                     = "GL_VERSION_1_2";
+  public static final String VERSION_1_4                     = "GL_VERSION_1_4";
+  public static final String VERSION_1_5                     = "GL_VERSION_1_5";
+  public static final String VERSION_2_0                     = "GL_VERSION_2_0";
+  
+  public static final String ARB_debug_output                = "GL_ARB_debug_output";
+  public static final String AMD_debug_output                = "GL_AMD_debug_output";
+    
+  public static final String ARB_framebuffer_object          = "GL_ARB_framebuffer_object";
+  public static final String OES_framebuffer_object          = "GL_OES_framebuffer_object";
+  public static final String EXT_framebuffer_object          = "GL_EXT_framebuffer_object";
+  public static final String EXT_framebuffer_blit            = "GL_EXT_framebuffer_blit";
+  public static final String EXT_framebuffer_multisample     = "GL_EXT_framebuffer_multisample";
+  public static final String EXT_packed_depth_stencil        = "GL_EXT_packed_depth_stencil";
+  public static final String OES_depth24                     = "GL_OES_depth24";
+  public static final String OES_depth32                     = "GL_OES_depth32";
+  public static final String OES_packed_depth_stencil        = "GL_OES_packed_depth_stencil";
+  public static final String NV_fbo_color_attachments        = "GL_NV_fbo_color_attachments";
+  
+  public static final String ARB_ES2_compatibility           = "GL_ARB_ES2_compatibility";
+  
+  public static final String EXT_abgr                        = "GL_EXT_abgr";
+  public static final String OES_rgb8_rgba8                  = "GL_OES_rgb8_rgba8";
+  public static final String OES_stencil1                    = "GL_OES_stencil1";
+  public static final String OES_stencil4                    = "GL_OES_stencil4";
+  public static final String OES_stencil8                    = "GL_OES_stencil8";
+  public static final String APPLE_float_pixels              = "GL_APPLE_float_pixels";
+  
+  public static final String ARB_texture_non_power_of_two    = "GL_ARB_texture_non_power_of_two";
+  public static final String ARB_texture_rectangle           = "GL_ARB_texture_rectangle";
+  public static final String EXT_texture_rectangle           = "GL_EXT_texture_rectangle";
+  public static final String NV_texture_rectangle            = "GL_NV_texture_rectangle";
+  public static final String EXT_texture_format_BGRA8888     = "GL_EXT_texture_format_BGRA8888";
+  public static final String IMG_texture_format_BGRA8888     = "GL_IMG_texture_format_BGRA8888";
+  public static final String EXT_texture_compression_s3tc    = "GL_EXT_texture_compression_s3tc";
+  public static final String NV_texture_compression_vtc      = "GL_NV_texture_compression_vtc";
+  public static final String SGIS_generate_mipmap            = "GL_SGIS_generate_mipmap";
+  public static final String OES_read_format                 = "GL_OES_read_format";
+  
+  public static final String OES_EGL_image_external          = "GL_OES_EGL_image_external";
+  
+  //
+  // Aliased GLX/WGL/.. extensions
+  //
+  
+  public static final String ARB_pixel_format                = "GL_ARB_pixel_format"; 
+  public static final String ARB_pbuffer                     = "GL_ARB_pbuffer";
+}
diff --git a/src/jogl/classes/com/jogamp/opengl/JoglVersion.java b/src/jogl/classes/com/jogamp/opengl/JoglVersion.java
index 75785fd86..cdb4b82bb 100644
--- a/src/jogl/classes/com/jogamp/opengl/JoglVersion.java
+++ b/src/jogl/classes/com/jogamp/opengl/JoglVersion.java
@@ -93,11 +93,13 @@ public class JoglVersion extends JogampVersion {
         return sb;        
     }
     
-    public static StringBuilder getDefaultOpenGLInfo(StringBuilder sb, boolean withCapabilitiesInfo) {
+    public static StringBuilder getDefaultOpenGLInfo(AbstractGraphicsDevice device, StringBuilder sb, boolean withCapabilitiesInfo) {
         if(null==sb) {
             sb = new StringBuilder();
         }
-        final AbstractGraphicsDevice device = GLProfile.getDefaultDevice();
+        if(null == device) {
+            device = GLProfile.getDefaultDevice();
+        }
         sb.append("Default Profiles on device ").append(device).append(Platform.getNewline());
         if(null!=device) {
             GLProfile.glAvailabilityToString(device, sb, "\t", 1);
@@ -120,13 +122,21 @@ public class JoglVersion extends JogampVersion {
         if(null==sb) {
             sb = new StringBuilder();
         }
-        GLContext ctx = gl.getContext();
-
+        
         sb.append(VersionUtil.SEPERATOR).append(Platform.getNewline());
         sb.append(device.getClass().getSimpleName()).append("[type ")
                 .append(device.getType()).append(", connection ").append(device.getConnection()).append("]: ").append(Platform.getNewline());
         GLProfile.glAvailabilityToString(device, sb, "\t", 1);        
         sb.append(Platform.getNewline());
+
+        return getGLStrings(gl, sb);
+    }
+    
+    public static StringBuilder getGLStrings(GL gl, StringBuilder sb) {        
+        if(null==sb) {
+            sb = new StringBuilder();
+        }
+        final GLContext ctx = gl.getContext();
         sb.append("Swap Interval  ").append(gl.getSwapInterval());
         sb.append(Platform.getNewline());
         sb.append("GL Profile     ").append(gl.getGLProfile());
diff --git a/src/jogl/classes/com/jogamp/opengl/OffscreenAutoDrawable.java b/src/jogl/classes/com/jogamp/opengl/OffscreenAutoDrawable.java
new file mode 100644
index 000000000..1ea8595c6
--- /dev/null
+++ b/src/jogl/classes/com/jogamp/opengl/OffscreenAutoDrawable.java
@@ -0,0 +1,89 @@
+/**
+ * Copyright 2012 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ * 
+ *    1. Redistributions of source code must retain the above copyright notice, this list of
+ *       conditions and the following disclaimer.
+ * 
+ *    2. Redistributions in binary form must reproduce the above copyright notice, this list
+ *       of conditions and the following disclaimer in the documentation and/or other materials
+ *       provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * 
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
+
+package com.jogamp.opengl;
+
+import javax.media.opengl.GLAutoDrawableDelegate;
+import javax.media.opengl.GLContext;
+import javax.media.opengl.GLDrawable;
+import javax.media.opengl.GLException;
+
+import jogamp.opengl.GLFBODrawableImpl;
+
+/** 
+ * Platform-independent class exposing FBO offscreen functionality to
+ * applications.
+ * <p>
+ * This class distinguishes itself from {@link GLAutoDrawableDelegate}
+ * with it's {@link #setSize(int, int)} functionality.
+ * </p>
+ */
+public class OffscreenAutoDrawable extends GLAutoDrawableDelegate {
+  
+    public OffscreenAutoDrawable(GLDrawable drawable, GLContext context, Object upstreamWidget) {
+        super(drawable, context, upstreamWidget);
+    }
+
+    /**
+     * Attempts to resize this offscreen auto drawable, if supported
+     * by the underlying {@link GLDrawable).
+     * @param newWidth
+     * @param newHeight
+     * @return <code>true</code> if resize was executed, otherwise <code>false</code>.
+     * @throws GLException in case of an error during the resize operation
+     */
+    public boolean setSize(int newWidth, int newHeight) throws GLException {
+        boolean done = false;
+        if(drawable instanceof GLFBODrawableImpl) {
+            context.makeCurrent();
+            try {                        
+                ((GLFBODrawableImpl)drawable).setSize(context.getGL(), newWidth, newHeight);
+                done = true;
+            } finally {
+                context.release();
+            }
+        }
+        if(done) {
+            this.defaultWindowResizedOp();
+            return true;
+        }
+        return false;
+    }
+    
+    /**
+     * If the underlying {@link GLDrawable} is an FBO implementation
+     * and contains an {#link FBObject}, the same is returned.
+     * Otherwise returns <code>null</code>.
+     */
+    public FBObject getFBObject() { 
+        if(drawable instanceof GLFBODrawableImpl) {
+            return ((GLFBODrawableImpl)drawable).getFBObject();
+        }
+        return null;
+    }
+}
diff --git a/src/jogl/classes/com/jogamp/opengl/swt/GLCanvas.java b/src/jogl/classes/com/jogamp/opengl/swt/GLCanvas.java
index 5ee58b78d..0d9d3ddf5 100644
--- a/src/jogl/classes/com/jogamp/opengl/swt/GLCanvas.java
+++ b/src/jogl/classes/com/jogamp/opengl/swt/GLCanvas.java
@@ -231,6 +231,8 @@ public class GLCanvas extends Canvas implements GLAutoDrawable {
 
       /* Get the nativewindow-Graphics Device associated with this control (which is determined by the parent Composite) */
       device = SWTAccessor.getDevice(this);
+      /* Since we have no means of querying the screen index yet, assume 0. Good choice due to Xinerama alike settings anyways. */
+      final int screenIdx = 0;
       /* Native handle for the control, used to associate with GLContext */
       nativeWindowHandle = SWTAccessor.getWindowHandle(this);
 
@@ -243,7 +245,7 @@ public class GLCanvas extends Canvas implements GLAutoDrawable {
       final GLDrawableFactory glFactory = GLDrawableFactory.getFactory(caps.getGLProfile());
 
       /* Create a NativeWindow proxy for the SWT canvas */
-      proxySurface = glFactory.createProxySurface(device, nativeWindowHandle, caps, chooser);
+      proxySurface = glFactory.createProxySurface(device, screenIdx, nativeWindowHandle, caps, chooser, swtCanvasUpStreamHook);
 
       /* Associate a GL surface with the proxy */
       drawable = glFactory.createGLDrawable(proxySurface);
@@ -265,12 +267,58 @@ public class GLCanvas extends Canvas implements GLAutoDrawable {
       addControlListener(new ControlAdapter() {
          @Override
          public void controlResized(final ControlEvent arg0) {
-            clientArea = GLCanvas.this.getClientArea();
-            /* Mark for OpenGL reshape next time the control is painted */
-            sendReshape = true;
+            updateSizeCheck();
          }
       });
    }
+   private final ProxySurface.UpstreamSurfaceHook swtCanvasUpStreamHook = new ProxySurface.UpstreamSurfaceHook() {
+    @Override
+    public final void create(ProxySurface s) { /* nop */ }
+
+    @Override
+    public final void destroy(ProxySurface s) { /* nop */ }
+
+    @Override
+    public final int getWidth(ProxySurface s) {
+        return clientArea.width;
+    }
+
+    @Override
+    public final int getHeight(ProxySurface s) {
+        return clientArea.height;
+    }
+    
+    @Override
+    public String toString() {
+        return "SETUpstreamSurfaceHook[upstream: "+GLCanvas.this.toString()+"]";
+    }
+
+   };
+
+   protected final void updateSizeCheck() {
+      clientArea = GLCanvas.this.getClientArea();
+      if (clientArea != null && 
+          proxySurface.getWidth() != clientArea.width && 
+          proxySurface.getHeight() != clientArea.height) {
+          sendReshape = true; // Mark for OpenGL reshape next time the control is painted
+      }
+      sendReshape = false;
+   }
+
+   @Override
+   public final Object getUpstreamWidget() {
+       return this;
+   }
+   
+   @Override
+   public int getWidth() {
+      return clientArea.width;
+   }
+
+   @Override
+   public int getHeight() {
+      return clientArea.height;
+   }
 
    @Override
    public void addGLEventListener(final GLEventListener arg0) {
@@ -418,25 +466,11 @@ public class GLCanvas extends Canvas implements GLAutoDrawable {
    }
 
    @Override
-   public int getHeight() {
-      final Rectangle clientArea = this.clientArea;
-      if (clientArea == null) return 0;
-      return clientArea.height;
-   }
-
-   @Override
    public NativeSurface getNativeSurface() {
       return (drawable != null) ? drawable.getNativeSurface() : null;
    }
 
    @Override
-   public int getWidth() {
-      final Rectangle clientArea = this.clientArea;
-      if (clientArea == null) return 0;
-      return clientArea.width;
-   }
-
-   @Override
    public boolean isRealized() {
       return (drawable != null) ? drawable.isRealized() : false;
    }
@@ -515,7 +549,7 @@ public class GLCanvas extends Canvas implements GLAutoDrawable {
        // System.err.println(NativeWindowVersion.getInstance());
        System.err.println(JoglVersion.getInstance());
 
-       System.err.println(JoglVersion.getDefaultOpenGLInfo(null, true).toString());
+       System.err.println(JoglVersion.getDefaultOpenGLInfo(null, null, true).toString());
 
        final GLCapabilitiesImmutable caps = new GLCapabilities( GLProfile.getDefault(GLProfile.getDefaultDevice()) );
        final Display display = new Display();
diff --git a/src/jogl/classes/com/jogamp/opengl/util/FBObject.java b/src/jogl/classes/com/jogamp/opengl/util/FBObject.java
deleted file mode 100644
index 3e049a334..000000000
--- a/src/jogl/classes/com/jogamp/opengl/util/FBObject.java
+++ /dev/null
@@ -1,483 +0,0 @@
-/*
- * Copyright (c) 2008 Sun Microsystems, Inc. All Rights Reserved.
- * Copyright (c) 2011 JogAmp Community. All rights reserved.
- * 
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- * 
- * - Redistribution of source code must retain the above copyright
- *   notice, this list of conditions and the following disclaimer.
- * 
- * - Redistribution in binary form must reproduce the above copyright
- *   notice, this list of conditions and the following disclaimer in the
- *   documentation and/or other materials provided with the distribution.
- * 
- * Neither the name of Sun Microsystems, Inc. or the names of
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- * 
- * This software is provided "AS IS," without a warranty of any kind. ALL
- * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
- * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
- * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
- * MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
- * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
- * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
- * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
- * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
- * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
- * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
- * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
- * 
- */
-
-package com.jogamp.opengl.util;
-
-import javax.media.opengl.*;
-
-public class FBObject {
-    static final int MAX_FBO_TEXTURES = 32; // just for our impl .. not the real 'max' FBO color attachments
-    private int[] fbo_tex_names;
-    private int[] fbo_tex_units;
-    private int fbo_tex_num;
-    private int colorattachment_num;
-
-    private boolean initialized;
-    private int width, height;
-    private int fb, depth_rb, stencil_rb, vStatus;
-    private boolean bound;
-    
-    public FBObject(int width, int height) {
-        this.fbo_tex_names = new int[MAX_FBO_TEXTURES];
-        this.fbo_tex_units = new int[MAX_FBO_TEXTURES];
-        this.fbo_tex_num = 0;
-        this.colorattachment_num = 0;
-        this.initialized = false;
-        this.width = width;
-        this.height = height;
-        this.fb = 0;
-        this.depth_rb = 0;
-        this.stencil_rb = 0;
-        this.bound = false;
-    }        
-    
-    /**
-     * @return true if the FB status is valid, otherwise false
-     * @see #getStatus()
-     */
-    public boolean isStatusValid() {
-        switch(vStatus) {
-            case GL.GL_FRAMEBUFFER_COMPLETE:
-                return true;
-            case GL.GL_FRAMEBUFFER_UNSUPPORTED:
-            case GL.GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT:
-            case GL.GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT:
-            case GL.GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS:
-            case GL.GL_FRAMEBUFFER_INCOMPLETE_FORMATS:
-            //case GL2.GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER:
-            //case GL2.GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER:
-            //case GL2.GL_FRAMEBUFFER_INCOMPLETE_DUPLICATE_ATTACHMENT:
-            case 0:
-            default:
-                System.out.println("Framebuffer " + fb + " is incomplete: status = 0x" + Integer.toHexString(vStatus) + 
-                        " : " + getStatusString(vStatus));
-                return false;
-        }
-    }
-        
-    /** 
-     * @return The FB status. {@link GL.GL_FRAMEBUFFER_COMPLETE} if ok, otherwise return GL FBO error state or -1
-     * @see #validateStatus() 
-     */
-    public int getStatus() {
-        return vStatus;
-    }
-
-    public String getStatusString() {
-        return getStatusString(vStatus);
-    }
-    
-    public static final String getStatusString(int fbStatus) {
-        switch(fbStatus) {
-            case -1:
-                return "NOT A FBO";
-            case GL.GL_FRAMEBUFFER_COMPLETE:
-                return "OK";
-            case GL.GL_FRAMEBUFFER_UNSUPPORTED:
-                return("GL FBO: Unsupported framebuffer format");
-            case GL.GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT:
-                return("GL FBO: incomplete, incomplete attachment\n");
-            case GL.GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT:
-                return("GL FBO: incomplete, missing attachment");
-            case GL.GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS:
-                return("GL FBO: incomplete, attached images must have same dimensions");
-            case GL.GL_FRAMEBUFFER_INCOMPLETE_FORMATS:
-                 return("GL FBO: incomplete, attached images must have same format");
-            case GL2.GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER:
-                return("GL FBO: incomplete, missing draw buffer");
-            case GL2.GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER:
-                return("GL FBO: incomplete, missing read buffer");
-            case GL2.GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE:
-                return("GL FBO: incomplete, missing multisample buffer");
-            case 0:
-                return("GL FBO: incomplete, implementation fault");
-            default:
-                return("GL FBO: incomplete, implementation ERROR");
-        }
-    }
-    
-    private boolean checkNoError(GL gl, int err, String exceptionMessage) {
-        if(GL.GL_NO_ERROR != err) {
-            if(null != gl) {
-                destroy(gl);
-            }
-            if(null != exceptionMessage) {
-                throw new GLException(exceptionMessage+" GL Error 0x"+Integer.toHexString(err));
-            }
-            return false;
-        }
-        return true;
-    }
-
-    private final void checkInitialized() {
-        if(!initialized) {
-            throw new GLException("FBO not initialized, call init(GL) first.");
-        }                
-    }
-    
-    private final void checkBound(GL gl, boolean shallBeBound) {
-        checkInitialized();
-        if(bound != shallBeBound) {
-            final String s0 = shallBeBound ? "not" : "already" ; 
-            throw new GLException("FBO "+s0+" bound "+toString());
-        }
-        checkNoError(null, gl.glGetError(), "FBObject pre"); // throws GLException if error
-    }
-
-    /**
-     * Initializes this FBO's instance with it's texture.
-     * 
-     * <p>Leaves the FBO bound!</p>
-     * 
-     * @param gl the current GL context
-     * @throws GLException in case of an error
-     */
-    public void init(GL gl) throws GLException {
-        if(initialized) {
-            throw new GLException("FBO already initialized");
-        }        
-        checkNoError(null, gl.glGetError(), "FBObject Init.pre"); // throws GLException if error
-                
-        // generate fbo ..
-        int name[] = new int[1];
-
-        gl.glGenFramebuffers(1, name, 0);
-        fb = name[0];
-        if(fb==0) {
-            throw new GLException("null generated framebuffer");
-        }
-
-        // bind fbo ..
-        gl.glBindFramebuffer(GL.GL_FRAMEBUFFER, fb);        
-        checkNoError(gl, gl.glGetError(), "FBObject Init.bindFB");  // throws GLException if error        
-        if(!gl.glIsFramebuffer(fb)) {
-            checkNoError(gl, GL.GL_INVALID_VALUE, "FBObject Init.isFB"); // throws GLException
-        }
-        bound = true;        
-        initialized = true;
-        
-        updateStatus(gl);        
-    }
-
-    /**
-     * Attaches a[nother] Texture2D Color Buffer to this FBO's instance,
-     * selecting the texture data type and format automatically.
-     * <p>This may be done as many times as many color attachments are supported,
-     * see {@link GL2GL3#GL_MAX_COLOR_ATTACHMENTS}.</p> 
-     * 
-     * <p>Assumes a bound FBO</p>
-     * <p>Leaves the FBO bound!</p>
-     * 
-     * @param gl the current GL context
-     * @param texUnit the desired texture unit ranging from [0..{@link GL2#GL_MAX_TEXTURE_UNITS}-1], or -1 if no unit shall be activate at {@link #use(GL, int)}
-     * @param magFilter if > 0 value for {@link GL#GL_TEXTURE_MAG_FILTER}
-     * @param minFilter if > 0 value for {@link GL#GL_TEXTURE_MIN_FILTER} 
-     * @param wrapS if > 0 value for {@link GL#GL_TEXTURE_WRAP_S}
-     * @param wrapT if > 0 value for {@link GL#GL_TEXTURE_WRAP_T}
-     * @return idx of the new attached texture, otherwise -1
-     * @throws GLException in case of an error
-     */
-    public int attachTexture2D(GL gl, int texUnit, int magFilter, int minFilter, int wrapS, int wrapT) throws GLException {
-        final int textureInternalFormat, textureDataFormat, textureDataType;
-        if(gl.isGLES()) { 
-            textureInternalFormat=GL.GL_RGBA;
-            textureDataFormat=GL.GL_RGBA;
-            textureDataType=GL.GL_UNSIGNED_BYTE;
-        } else { 
-            textureInternalFormat=GL.GL_RGBA8;
-            textureDataFormat=GL.GL_BGRA;
-            textureDataType=GL2GL3.GL_UNSIGNED_INT_8_8_8_8_REV;
-        }
-        return attachTexture2D(gl, texUnit, textureInternalFormat, textureDataFormat, textureDataType, magFilter, minFilter, wrapS, wrapT);
-    }
-    
-    /**
-     * Attaches a[nother] Texture2D Color Buffer to this FBO's instance,
-     * selecting the texture data type and format automatically.
-     * <p>This may be done as many times as many color attachments are supported,
-     * see {@link GL2GL3#GL_MAX_COLOR_ATTACHMENTS}.</p> 
-     * 
-     * <p>Assumes a bound FBO</p>
-     * <p>Leaves the FBO bound!</p>
-     * 
-     * @param gl the current GL context
-     * @param texUnit the desired texture unit ranging from [0..{@link GL2#GL_MAX_TEXTURE_UNITS}-1], or -1 if no unit shall be activate at {@link #use(GL, int)}
-     * @param textureInternalFormat internalFormat parameter to {@link GL#glTexImage2D(int, int, int, int, int, int, int, int, long)}
-     * @param textureDataFormat format parameter to {@link GL#glTexImage2D(int, int, int, int, int, int, int, int, long)}
-     * @param textureDataType type parameter to {@link GL#glTexImage2D(int, int, int, int, int, int, int, int, long)}
-     * @param magFilter if > 0 value for {@link GL#GL_TEXTURE_MAG_FILTER}
-     * @param minFilter if > 0 value for {@link GL#GL_TEXTURE_MIN_FILTER} 
-     * @param wrapS if > 0 value for {@link GL#GL_TEXTURE_WRAP_S}
-     * @param wrapT if > 0 value for {@link GL#GL_TEXTURE_WRAP_T}
-     * @return index of the texture colorbuffer if bound and configured successfully, otherwise -1
-     * @throws GLException in case the texture colorbuffer couldn't be allocated
-     */
-    public int attachTexture2D(GL gl, int texUnit,
-                               int textureInternalFormat, int textureDataFormat, int textureDataType,
-                               int magFilter, int minFilter, int wrapS, int wrapT) throws GLException {
-        checkBound(gl, true);
-        final int fbo_tex_idx = fbo_tex_num;
-        gl.glGenTextures(1, fbo_tex_names, fbo_tex_num);
-        if(fbo_tex_names[fbo_tex_idx]==0) {
-            throw new GLException("null generated texture");
-        }
-        fbo_tex_units[fbo_tex_idx] = texUnit;
-        fbo_tex_num++;
-        if(0<=texUnit) {
-            gl.glActiveTexture(GL.GL_TEXTURE0 + texUnit);
-        }
-        gl.glBindTexture(GL.GL_TEXTURE_2D, fbo_tex_names[fbo_tex_idx]);
-        checkNoError(gl, gl.glGetError(), "FBObject Init.bindTex");  // throws GLException if error        
-        gl.glTexImage2D(GL.GL_TEXTURE_2D, 0, textureInternalFormat, width, height, 0,
-                        textureDataFormat, textureDataType, null);
-        int glerr = gl.glGetError();
-        if(GL.GL_NO_ERROR != glerr) {
-            int[] sz = new int[1];
-            gl.glGetIntegerv(GL.GL_MAX_TEXTURE_SIZE, sz, 0);
-            // throws GLException if error
-            checkNoError(gl, glerr, "FBObject Init.texImage2D: "+
-                                    " int-fmt 0x"+Integer.toHexString(textureInternalFormat)+
-                                    ", "+width+"x"+height+
-                                    ", data-fmt 0x"+Integer.toHexString(textureDataFormat)+
-                                    ", data-type 0x"+Integer.toHexString(textureDataType)+
-                                    ", max tex-sz "+sz[0]);
-        }
-        if( 0 < magFilter ) {
-            gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MAG_FILTER, magFilter);
-        }
-        if( 0 < minFilter ) {
-            gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MIN_FILTER, minFilter);
-        }
-        if( 0 < wrapS ) {
-            gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_S, wrapS);
-        }
-        if( 0 < wrapT ) {
-            gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_T, wrapT);            
-        }
-
-        // Set up the color buffer for use as a renderable texture:
-        gl.glFramebufferTexture2D(GL.GL_FRAMEBUFFER,
-                                  GL.GL_COLOR_ATTACHMENT0 + colorattachment_num++,
-                                  GL.GL_TEXTURE_2D, fbo_tex_names[fbo_tex_idx], 0); 
-
-        updateStatus(gl);                
-        return isStatusValid() ? fbo_tex_idx : -1;
-    }
-    
-    /**
-     * Attaches one Depth Buffer to this FBO's instance.
-     * <p>This may be done only one time.</p>
-     * 
-     * <p>Assumes a bound FBO</p>
-     * <p>Leaves the FBO bound!</p>
-     * @param gl the current GL context
-     * @param depthComponentType {@link GL#GL_DEPTH_COMPONENT16}, {@link GL#GL_DEPTH_COMPONENT24} or {@link GL#GL_DEPTH_COMPONENT32}
-     * @return true if the depth renderbuffer could be bound and configured, otherwise false
-     * @throws GLException in case the depth renderbuffer couldn't be allocated or one is already attached.
-     */
-    public boolean attachDepthBuffer(GL gl, int depthComponentType) throws GLException {
-        checkBound(gl, true);
-        if(depth_rb != 0) {
-            throw new GLException("FBO depth buffer already attached (rb "+depth_rb+")");
-        }        
-        int name[] = new int[1];
-        gl.glGenRenderbuffers(1, name, 0);
-        depth_rb = name[0];        
-        if(depth_rb==0) {
-            throw new GLException("null generated renderbuffer");
-        }
-        // Initialize the depth buffer:
-        gl.glBindRenderbuffer(GL.GL_RENDERBUFFER, depth_rb);
-        if(!gl.glIsRenderbuffer(depth_rb)) {
-            System.err.println("not a depthbuffer: "+ depth_rb);
-            name[0] = depth_rb;
-            gl.glDeleteRenderbuffers(1, name, 0);
-            depth_rb=0;
-            return false;            
-        }
-        
-        gl.glRenderbufferStorage(GL.GL_RENDERBUFFER, depthComponentType, width, height);
-        // Set up the depth buffer attachment:
-        gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER,
-                                     GL.GL_DEPTH_ATTACHMENT,
-                                     GL.GL_RENDERBUFFER, depth_rb);
-        updateStatus(gl);
-        return isStatusValid();                
-    }
-    
-    /**
-     * Attaches one Stencil Buffer to this FBO's instance.
-     * <p>This may be done only one time.</p>
-     * 
-     * <p>Assumes a bound FBO</p>
-     * <p>Leaves the FBO bound!</p>
-     * @param gl the current GL context
-     * @param stencilComponentType {@link GL#GL_STENCIL_INDEX1}, {@link GL#GL_STENCIL_INDEX4} or {@link GL#GL_STENCIL_INDEX8}
-     * @return true if the stencil renderbuffer could be bound and configured, otherwise false
-     * @throws GLException in case the stencil renderbuffer couldn't be allocated  or one is already attached.
-     */
-    public boolean attachStencilBuffer(GL gl, int stencilComponentType) throws GLException {
-        checkBound(gl, true);
-        if(stencil_rb != 0) {
-            throw new GLException("FBO stencil buffer already attached (rb "+stencil_rb+")");
-        }
-        int name[] = new int[1];
-        gl.glGenRenderbuffers(1, name, 0);
-        stencil_rb = name[0];
-        if(stencil_rb==0) {
-            throw new GLException("null generated stencilbuffer");
-        }
-        // Initialize the stencil buffer:
-        gl.glBindRenderbuffer(GL.GL_RENDERBUFFER, stencil_rb);
-        if(!gl.glIsRenderbuffer(stencil_rb)) {
-            System.err.println("not a stencilbuffer: "+ stencil_rb);
-            name[0] = stencil_rb;
-            gl.glDeleteRenderbuffers(1, name, 0);
-            stencil_rb=0;
-            return false;
-        }
-        gl.glRenderbufferStorage(GL.GL_RENDERBUFFER, stencilComponentType, width, height);
-        gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER,
-                                     GL.GL_STENCIL_ATTACHMENT,
-                                     GL.GL_RENDERBUFFER, stencil_rb);
-        updateStatus(gl);        
-        return isStatusValid();                
-    }
-
-    /**
-     * @param gl the current GL context
-     */
-    public void destroy(GL gl) {
-        if(bound) {
-            unbind(gl);
-        }
-
-        int name[] = new int[1];
-
-        if(0!=stencil_rb) {
-            name[0] = stencil_rb;
-            gl.glDeleteRenderbuffers(1, name, 0);
-            stencil_rb = 0;
-        }
-        if(0!=depth_rb) {
-            name[0] = depth_rb;
-            gl.glDeleteRenderbuffers(1, name, 0);
-            depth_rb=0;
-        }
-        if(null!=fbo_tex_names && fbo_tex_num>0) {
-            gl.glDeleteTextures(1, fbo_tex_names, fbo_tex_num);
-            fbo_tex_names = new int[MAX_FBO_TEXTURES];
-            fbo_tex_units = new int[MAX_FBO_TEXTURES];
-            fbo_tex_num = 0;
-        }
-        colorattachment_num = 0;
-        if(0!=fb) {
-            name[0] = fb;
-            gl.glDeleteFramebuffers(1, name, 0);
-            fb = 0;
-        }
-        initialized = false;
-    }
-
-    /** 
-     * Bind this FBO 
-     * <p>In case you have attached more than one color buffer,
-     * you may want to setup {@link GL2GL3#glDrawBuffers(int, int[], int)}.</p>
-     * @param gl the current GL context
-     */
-    public void bind(GL gl) {
-        checkBound(gl, false);
-        gl.glBindFramebuffer(GL.GL_FRAMEBUFFER, fb);
-        bound = true;
-    }
-
-    /** 
-     * Unbind FBO, ie bind 'non' FBO 0 
-     * @param gl the current GL context
-     */
-    public void unbind(GL gl) {
-        checkBound(gl, true);
-        gl.glBindFramebuffer(GL.GL_FRAMEBUFFER, 0);
-        bound = false;
-    }
-
-    /** 
-     * Bind the texture with given index.
-     * 
-     * <p>If a valid texture unit was named via {@link #attachTexture2D(GL, int, int, int, int, int) attachTexture2D(..)},
-     * the unit is activated via {@link GL#glActiveTexture(int) glActiveTexture(GL.GL_TEXTURE0 + unit)}.</p>
-     * @param gl the current GL context
-     * @param texIdx index of the texture to use, prev. attached w/  {@link #attachTexture2D(GL, int, int, int, int, int) attachTexture2D(..)}  
-     */
-    public void use(GL gl, int texIdx) {
-        checkBound(gl, false);
-        if(texIdx >= fbo_tex_num) {
-            throw new GLException("Invalid texId, only "+fbo_tex_num+" textures are attached");
-        }
-        if(0<=fbo_tex_units[texIdx]) {
-            gl.glActiveTexture(GL.GL_TEXTURE0 + fbo_tex_units[texIdx]);
-        }
-        gl.glBindTexture(GL.GL_TEXTURE_2D, fbo_tex_names[texIdx]); // use it ..
-    }
-
-    /** Unbind texture, ie bind 'non' texture 0 */    
-    public void unuse(GL gl) {
-        checkBound(gl, false);
-        gl.glBindTexture(GL.GL_TEXTURE_2D, 0); // don't use it
-    }
-    
-    public final boolean isBound() { return bound; }
-    public final int getWidth() { return width; }
-    public final int getHeight() { return height; }       
-    public final int getFBName() { return fb; }
-    public final int getTextureNumber() { return fbo_tex_num; }
-    public final int getTextureName(int idx) { return fbo_tex_names[idx]; }
-    
-    /** @return the named texture unit ranging from [0..{@link GL2#GL_MAX_TEXTURE_UNITS}-1], or -1 if no unit was desired. */
-    public final int getTextureUnit(int idx) { return fbo_tex_units[idx]; }
-    public final int getColorAttachmentNumber() { return colorattachment_num; }
-    public final int getStencilBuffer() { return stencil_rb; }
-    public final int getDepthBuffer() { return depth_rb; }
-    public final String toString() {
-        return "FBO[name "+fb+", size "+width+"x"+height+", color num "+colorattachment_num+", tex num "+fbo_tex_num+", depth "+depth_rb+", stencil "+stencil_rb+"]";
-    }
-    
-    private void updateStatus(GL gl) {
-        if(!gl.glIsFramebuffer(fb)) {
-            vStatus = -1;
-        } else {
-            vStatus = gl.glCheckFramebufferStatus(GL.GL_FRAMEBUFFER);
-        }
-    }       
-}
diff --git a/src/jogl/classes/com/jogamp/opengl/util/GLBuffers.java b/src/jogl/classes/com/jogamp/opengl/util/GLBuffers.java
index 8401b9cd2..331d6fa4e 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/GLBuffers.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/GLBuffers.java
@@ -39,6 +39,7 @@
 package com.jogamp.opengl.util;
 
 import com.jogamp.common.nio.Buffers;
+
 import javax.media.opengl.GL;
 import javax.media.opengl.GL2;
 import javax.media.opengl.GL2ES2;
@@ -56,22 +57,32 @@ import java.nio.*;
 public class GLBuffers extends Buffers {
 
     /**
-     * @param glType shall be one of 
-     *              GL_UNSIGNED_BYTE, GL_BYTE, GL_UNSIGNED_SHORT, GL_SHORT,
-     *              GL_UNSIGNED_INT, GL_INT, GL_HALF_FLOAT, GL_FLOAT, GL_DOUBLE, 
-     *              GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
-     *              GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, 
-     *              GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, 
-     *              GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
-     *              GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV, 
-     *              GL_UNSIGNED_INT_10_10_10_2, GL_UNSIGNED_INT_2_10_10_10_REV
-     *              GL_UNSIGNED_INT_24_8, GL_UNSIGNED_INT_10F_11F_11F_REV,
-     *              GL_UNSIGNED_INT_5_9_9_9_REV, GL_FLOAT_32_UNSIGNED_INT_24_8_REV,         
-     *              GL_HILO16_NV, GL_SIGNED_HILO16_NV (27)         
+     * @param glType shall be one of (29) <br/>
+     *              GL_BYTE, GL_UNSIGNED_BYTE, <br/>
+     *              GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV, <br/>
+     *              <br/>
+     *              GL_SHORT, GL_UNSIGNED_SHORT, <br/>
+     *              GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, <br/> 
+     *              GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, <br/>
+     *              GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV, <br/>
+     *              GL.GL_HALF_FLOAT, GLES2.GL_HALF_FLOAT_OES: <br/>
+     *              <br/>
+     *              GL_FIXED, GL_INT <br/>
+     *              GL_UNSIGNED_INT, GL_UNSIGNED_INT_8_8_8_8, <br/>
+     *              GL_UNSIGNED_INT_8_8_8_8_REV, GL_UNSIGNED_INT_10_10_10_2, <br/> 
+     *              GL_UNSIGNED_INT_2_10_10_10_REV, GL_UNSIGNED_INT_24_8, <br/>
+     *              GL_UNSIGNED_INT_10F_11F_11F_REV, GL_UNSIGNED_INT_5_9_9_9_REV <br/> 
+     *              GL_HILO16_NV, GL_SIGNED_HILO16_NV <br/>
+     *              <br/>
+     *              GL2GL3.GL_FLOAT_32_UNSIGNED_INT_24_8_REV <br/>
+     *              <br/>
+     *              GL_FLOAT, GL_DOUBLE <br/> 
+     *              
      * @return -1 if glType is unhandled, otherwise the actual value > 0 
      */
     public static final int sizeOfGLType(int glType) {
-        switch (glType) { // 25
+        switch (glType) { // 29
+            // case GL2.GL_BITMAP:
             case GL.GL_BYTE:
             case GL.GL_UNSIGNED_BYTE:
             case GL2GL3.GL_UNSIGNED_BYTE_3_3_2:
@@ -86,6 +97,8 @@ public class GLBuffers extends Buffers {
             case GL2GL3.GL_UNSIGNED_SHORT_4_4_4_4_REV:
             case GL2GL3.GL_UNSIGNED_SHORT_5_5_5_1:
             case GL2GL3.GL_UNSIGNED_SHORT_1_5_5_5_REV:
+            case GL.GL_HALF_FLOAT:
+            case GLES2.GL_HALF_FLOAT_OES:
                 return SIZEOF_SHORT;
                                 
             case GL.GL_FIXED:
@@ -108,29 +121,38 @@ public class GLBuffers extends Buffers {
             case GL.GL_FLOAT:
                 return SIZEOF_FLOAT;
                 
-            case GL2.GL_DOUBLE:
+            case GL2GL3.GL_DOUBLE:
                 return SIZEOF_DOUBLE;
         }
         return -1;
     }
     
     /**
-     * @param glType shall be one of 
-     *              GL_UNSIGNED_BYTE, GL_BYTE, GL_UNSIGNED_SHORT, GL_SHORT,
-     *              GL_UNSIGNED_INT, GL_INT, GL_HALF_FLOAT, GL_FLOAT, GL_DOUBLE, 
-     *              GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
-     *              GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, 
-     *              GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, 
-     *              GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
-     *              GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV, 
-     *              GL_UNSIGNED_INT_10_10_10_2, GL_UNSIGNED_INT_2_10_10_10_REV
-     *              GL_UNSIGNED_INT_24_8, GL_UNSIGNED_INT_10F_11F_11F_REV,
-     *              GL_UNSIGNED_INT_5_9_9_9_REV, GL_FLOAT_32_UNSIGNED_INT_24_8_REV,         
-     *              GL_HILO16_NV, GL_SIGNED_HILO16_NV (27)         
+     * @param glType shall be one of (29) <br/>
+     *              GL_BYTE, GL_UNSIGNED_BYTE, <br/>
+     *              GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV, <br/>
+     *              <br/>
+     *              GL_SHORT, GL_UNSIGNED_SHORT, <br/>
+     *              GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, <br/> 
+     *              GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, <br/>
+     *              GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV, <br/>
+     *              GL_HALF_FLOAT, GL_HALF_FLOAT_OES <br/>
+     *              <br/>
+     *              GL_FIXED, GL_INT <br/>
+     *              GL_UNSIGNED_INT, GL_UNSIGNED_INT_8_8_8_8, <br/>
+     *              GL_UNSIGNED_INT_8_8_8_8_REV, GL_UNSIGNED_INT_10_10_10_2, <br/> 
+     *              GL_UNSIGNED_INT_2_10_10_10_REV, GL_UNSIGNED_INT_24_8, <br/>
+     *              GL_UNSIGNED_INT_10F_11F_11F_REV, GL_UNSIGNED_INT_5_9_9_9_REV <br/> 
+     *              GL_HILO16_NV, GL_SIGNED_HILO16_NV <br/>
+     *              <br/>
+     *              GL_FLOAT_32_UNSIGNED_INT_24_8_REV <br/>
+     *              <br/>
+     *              GL_FLOAT, GL_DOUBLE <br/> 
+     *              
      * @return null if glType is unhandled, otherwise the new Buffer object 
      */
     public static final Buffer newDirectGLBuffer(int glType, int numElements) {
-        switch (glType) {
+        switch (glType) { // 29
             case GL.GL_BYTE:
             case GL.GL_UNSIGNED_BYTE:
             case GL2GL3.GL_UNSIGNED_BYTE_3_3_2:
@@ -145,6 +167,8 @@ public class GLBuffers extends Buffers {
             case GL2GL3.GL_UNSIGNED_SHORT_4_4_4_4_REV:
             case GL2GL3.GL_UNSIGNED_SHORT_5_5_5_1:
             case GL2GL3.GL_UNSIGNED_SHORT_1_5_5_5_REV:
+            case GL.GL_HALF_FLOAT:
+            case GLES2.GL_HALF_FLOAT_OES:
                 return newDirectShortBuffer(numElements);
                 
             case GL.GL_FIXED:
@@ -174,18 +198,26 @@ public class GLBuffers extends Buffers {
     }
 
     /**
-     * @param glType shall be one of 
-     *              GL_UNSIGNED_BYTE, GL_BYTE, GL_UNSIGNED_SHORT, GL_SHORT,
-     *              GL_UNSIGNED_INT, GL_INT, GL_HALF_FLOAT, GL_FLOAT, GL_DOUBLE, 
-     *              GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
-     *              GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, 
-     *              GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, 
-     *              GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
-     *              GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV, 
-     *              GL_UNSIGNED_INT_10_10_10_2, GL_UNSIGNED_INT_2_10_10_10_REV
-     *              GL_UNSIGNED_INT_24_8, GL_UNSIGNED_INT_10F_11F_11F_REV,
-     *              GL_UNSIGNED_INT_5_9_9_9_REV, GL_FLOAT_32_UNSIGNED_INT_24_8_REV,      
-     *              GL_HILO16_NV, GL_SIGNED_HILO16_NV (27)         
+     * @param glType shall be one of (29) <br/>
+     *              GL_BYTE, GL_UNSIGNED_BYTE, <br/>
+     *              GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV, <br/>
+     *              <br/>
+     *              GL_SHORT, GL_UNSIGNED_SHORT, <br/>
+     *              GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, <br/> 
+     *              GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, <br/>
+     *              GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV, <br/>
+     *              GL_HALF_FLOAT, GL_HALF_FLOAT_OES <br/>
+     *              <br/>
+     *              GL_FIXED, GL_INT <br/>
+     *              GL_UNSIGNED_INT, GL_UNSIGNED_INT_8_8_8_8, <br/>
+     *              GL_UNSIGNED_INT_8_8_8_8_REV, GL_UNSIGNED_INT_10_10_10_2, <br/> 
+     *              GL_UNSIGNED_INT_2_10_10_10_REV, GL_UNSIGNED_INT_24_8, <br/>
+     *              GL_UNSIGNED_INT_10F_11F_11F_REV, GL_UNSIGNED_INT_5_9_9_9_REV <br/> 
+     *              GL_HILO16_NV, GL_SIGNED_HILO16_NV <br/>
+     *              <br/>
+     *              GL_FLOAT_32_UNSIGNED_INT_24_8_REV <br/>
+     *              <br/>
+     *              GL_FLOAT, GL_DOUBLE <br/> 
      * @return null if glType is unhandled or parent is null or bufLen is 0, otherwise the new Buffer object 
      */
     public static final Buffer sliceGLBuffer(ByteBuffer parent, int bytePos, int byteLen, int glType) {
@@ -195,7 +227,7 @@ public class GLBuffers extends Buffers {
         parent.position(bytePos);
         parent.limit(bytePos + byteLen);
 
-        switch (glType) {
+        switch (glType) { // 29
             case GL.GL_BYTE:
             case GL.GL_UNSIGNED_BYTE:
             case GL2GL3.GL_UNSIGNED_BYTE_3_3_2:
@@ -210,6 +242,8 @@ public class GLBuffers extends Buffers {
             case GL2GL3.GL_UNSIGNED_SHORT_4_4_4_4_REV:
             case GL2GL3.GL_UNSIGNED_SHORT_5_5_5_1:
             case GL2GL3.GL_UNSIGNED_SHORT_1_5_5_5_REV:
+            case GL.GL_HALF_FLOAT:
+            case GLES2.GL_HALF_FLOAT_OES:
                 return parent.asShortBuffer();
                 
             case GL.GL_FIXED:
@@ -362,28 +396,46 @@ public class GLBuffers extends Buffers {
      * 
      * @param tmp a pass through integer array of size >= 1 used to store temp data (performance)
      * 
-     * @param format must be one of 
-     *              GL_COLOR_INDEX, GL_STENCIL_INDEX, GL_DEPTH_COMPONENT, GL_DEPTH_STENCIL,
-     *              GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA, GL_LUMINANCE,
-     *              GL_RG, GL_LUMINANCE_ALPHA,
-     *              GL_RGB, GL_BGR, GL_RGBA, GL_BGRA, GL_ABGR_EXT,
-     *              GL_RED_INTEGER, GL_GREEN_INTEGER, GL_BLUE_INTEGER,
-     *              GL_RG_INTEGER, GL_RGB_INTEGER, GL_BGR_INTEGER, 
-     *              GL_RGBA_INTEGER, GL_BGRA_INTEGER, GL_HILO_NV, GL_SIGNED_HILO_NV (26)
+     * @param format must be one of (26) <br/> 
+     *              GL_COLOR_INDEX GL_STENCIL_INDEX <br/> 
+     *              GL_DEPTH_COMPONENT GL_DEPTH_STENCIL <br/> 
+     *              GL_RED GL_RED_INTEGER <br/> 
+     *              GL_GREEN GL_GREEN_INTEGER <br/> 
+     *              GL_BLUE GL_BLUE_INTEGER <br/> 
+     *              GL_ALPHA GL_LUMINANCE (12) <br/> 
+     *              <br/> 
+     *              GL_LUMINANCE_ALPHA GL_RG <br/>
+     *              GL_RG_INTEGER GL_HILO_NV <br/> 
+     *              GL_SIGNED_HILO_NV (5) <br/> 
+     *              <br/> 
+     *              GL_RGB GL_RGB_INTEGER <br/> 
+     *              GL_BGR GL_BGR_INTEGER (4)<br/>  
+     *              <br/> 
+     *              GL_RGBA GL_RGBA_INTEGER <br/> 
+     *              GL_BGRA GL_BGRA_INTEGER <br/>
+     *              GL_ABGR_EXT (5)<br/> 
      *           
-     * @param type must be one of 
-     *              GL_BITMAP, 
-     *              GL_UNSIGNED_BYTE, GL_BYTE, GL_UNSIGNED_SHORT, GL_SHORT,
-     *              GL_UNSIGNED_INT, GL_INT, GL_HALF_FLOAT, GL_FLOAT, GL_DOUBLE, 
-     *              GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
-     *              GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, 
-     *              GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, 
-     *              GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
-     *              GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV, 
-     *              GL_UNSIGNED_INT_10_10_10_2, GL_UNSIGNED_INT_2_10_10_10_REV
-     *              GL_UNSIGNED_INT_24_8, GL_UNSIGNED_INT_10F_11F_11F_REV,
-     *              GL_UNSIGNED_INT_5_9_9_9_REV, GL_FLOAT_32_UNSIGNED_INT_24_8_REV,
-     *              GL_HILO16_NV, GL_SIGNED_HILO16_NV (28)         
+     * @param type must be one of (30) <br/>  
+     *              GL_BITMAP, <br/> 
+     *              GL_BYTE, GL_UNSIGNED_BYTE, <br/>
+     *              GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV, <br/>
+     *              <br/>
+     *              GL_SHORT, GL_UNSIGNED_SHORT, <br/>
+     *              GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, <br/> 
+     *              GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV, <br/>
+     *              GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV, <br/>
+     *              GL_HALF_FLOAT, GL_HALF_FLOAT_OES <br/>
+     *              <br/>
+     *              GL_FIXED, GL_INT <br/>
+     *              GL_UNSIGNED_INT, GL_UNSIGNED_INT_8_8_8_8, <br/>
+     *              GL_UNSIGNED_INT_8_8_8_8_REV, GL_UNSIGNED_INT_10_10_10_2, <br/> 
+     *              GL_UNSIGNED_INT_2_10_10_10_REV, GL_UNSIGNED_INT_24_8, <br/>
+     *              GL_UNSIGNED_INT_10F_11F_11F_REV, GL_UNSIGNED_INT_5_9_9_9_REV <br/> 
+     *              GL_HILO16_NV, GL_SIGNED_HILO16_NV <br/>
+     *              <br/>
+     *              GL_FLOAT_32_UNSIGNED_INT_24_8_REV <br/>
+     *              <br/>
+     *              GL_FLOAT, GL_DOUBLE <br/> 
      * 
      * @param width in pixels
      * @param height in pixels
@@ -402,7 +454,7 @@ public class GLBuffers extends Buffers {
         if (height < 0) return 0;
         if (depth < 0) return 0;
         
-        switch (format) /* 24 */ {
+        switch (format) /* 26 */ {
             case GL2.GL_COLOR_INDEX:
             case GL2GL3.GL_STENCIL_INDEX:
             case GL2GL3.GL_DEPTH_COMPONENT:
@@ -445,7 +497,7 @@ public class GLBuffers extends Buffers {
               throw new GLException("format 0x"+Integer.toHexString(format)+" not supported [yet], pls notify the maintainer in case this is our bug.");
         }
                 
-        switch (type) /* 26 */ {
+        switch (type) /* 30 */ {
             case GL2.GL_BITMAP:
               if (GL2.GL_COLOR_INDEX == format || GL2GL3.GL_STENCIL_INDEX == format) {
                 return (depth * (height * ((width+7)/8)));
@@ -460,6 +512,7 @@ public class GLBuffers extends Buffers {
             case GLES2.GL_HALF_FLOAT_OES:
               esize = 2;
               break;
+            case GL.GL_FIXED:
             case GL2ES2.GL_INT:
             case GL.GL_UNSIGNED_INT:
             case GL.GL_FLOAT:
diff --git a/src/jogl/classes/com/jogamp/opengl/util/GLReadBufferUtil.java b/src/jogl/classes/com/jogamp/opengl/util/GLReadBufferUtil.java
index 368cbc0a2..b0fae8a6d 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/GLReadBufferUtil.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/GLReadBufferUtil.java
@@ -35,6 +35,7 @@ import java.io.IOException;
 import java.nio.*;
 import javax.media.opengl.*;
 
+import com.jogamp.opengl.GLExtensions;
 import com.jogamp.opengl.util.texture.Texture;
 import com.jogamp.opengl.util.texture.TextureData;
 import com.jogamp.opengl.util.texture.TextureIO;
@@ -67,6 +68,10 @@ public class GLReadBufferUtil {
       return null!=readTextureData && null!=readPixelBuffer ;
     }
     
+    public boolean hasAlpha() { return 4 == components ? true : false ; }
+    
+    public GLPixelStorageModes getGLPixelStorageModes() { return psm; }
+    
     /**
      * @return the raw pixel ByteBuffer, filled by {@link #readPixels(GLAutoDrawable, boolean)}
      */
@@ -104,13 +109,14 @@ public class GLReadBufferUtil {
     /**
      * Read the drawable's pixels to TextureData and Texture, if requested at construction
      * 
-     * @param gl the current GL object
+     * @param gl the current GL context object. It's read drawable is being used as the pixel source.
      * @param drawable the drawable to read from
      * @param flip weather to flip the data vertically or not
      * 
      * @see #GLReadBufferUtil(boolean, boolean)
      */
-    public boolean readPixels(GL gl, GLDrawable drawable, boolean flip) {
+    public boolean readPixels(GL gl, boolean flip) {
+        final GLDrawable drawable = gl.getContext().getGLReadDrawable();
         final int textureInternalFormat, textureDataFormat, textureDataType;
         final int[] glImplColorReadVals = new int[] { 0, 0 };
         
@@ -118,7 +124,7 @@ public class GLReadBufferUtil {
             textureInternalFormat=GL.GL_RGB;
             textureDataFormat=GL.GL_RGB;
             textureDataType = GL.GL_UNSIGNED_BYTE;            
-        } else if(gl.isGLES2Compatible() || gl.isExtensionAvailable("GL_OES_read_format")) {
+        } else if(gl.isGLES2Compatible() || gl.isExtensionAvailable(GLExtensions.OES_read_format)) {
             gl.glGetIntegerv(GL.GL_IMPLEMENTATION_COLOR_READ_FORMAT, glImplColorReadVals, 0);
             gl.glGetIntegerv(GL.GL_IMPLEMENTATION_COLOR_READ_TYPE, glImplColorReadVals, 1);            
             textureInternalFormat = (4 == components) ? GL.GL_RGBA : GL.GL_RGB;
diff --git a/src/jogl/classes/com/jogamp/opengl/util/ImmModeSink.java b/src/jogl/classes/com/jogamp/opengl/util/ImmModeSink.java
index 3b817afcf..cf0373044 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/ImmModeSink.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/ImmModeSink.java
@@ -1,15 +1,20 @@
 
 package com.jogamp.opengl.util;
 
-import com.jogamp.common.util.*;
-import com.jogamp.opengl.util.glsl.ShaderState;
+import java.nio.Buffer;
+import java.nio.ByteBuffer;
+import java.nio.ShortBuffer;
+import java.util.ArrayList;
+import java.util.Iterator;
 
-import javax.media.opengl.*;
-import javax.media.opengl.fixedfunc.*;
+import javax.media.opengl.GL;
+import javax.media.opengl.GL2ES1;
+import javax.media.opengl.GL2ES2;
+import javax.media.opengl.GLException;
+import javax.media.opengl.fixedfunc.GLPointerFunc;
 
-import java.nio.*;
-import java.util.Iterator;
-import java.util.ArrayList;
+import com.jogamp.common.util.ReflectionUtil;
+import com.jogamp.opengl.util.glsl.ShaderState;
 
 public class ImmModeSink {
 
@@ -337,10 +342,8 @@ public class ImmModeSink {
         enableBuffer(gl, true);
 
         if (buffer!=null) {
-            GL2ES1 glf = gl.getGL2ES1();
-
             if(null==indices) {
-                glf.glDrawArrays(mode, 0, count);
+                gl.glDrawArrays(mode, 0, count);
             } else {
                 Class<?> clazz = indices.getClass();
                 int type=-1;
@@ -352,7 +355,7 @@ public class ImmModeSink {
                 if(0>type) {
                     throw new GLException("Given Buffer Class not supported: "+clazz+", should be ubyte or ushort:\n\t"+this);
                 }
-                glf.glDrawElements(mode, indices.remaining(), type, indices);
+                gl.glDrawElements(mode, indices.remaining(), type, indices);
                 // GL2: gl.glDrawRangeElements(mode, 0, indices.remaining()-1, indices.remaining(), type, indices);
             }
         }
diff --git a/src/jogl/classes/com/jogamp/opengl/util/awt/Screenshot.java b/src/jogl/classes/com/jogamp/opengl/util/awt/Screenshot.java
index fa66673fd..0022d5c2d 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/awt/Screenshot.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/awt/Screenshot.java
@@ -48,6 +48,7 @@ import javax.media.opengl.GLException;
 import javax.media.opengl.glu.gl2.GLUgl2;
 
 import com.jogamp.common.util.IOUtil;
+import com.jogamp.opengl.GLExtensions;
 import com.jogamp.opengl.util.GLPixelStorageModes;
 import com.jogamp.opengl.util.TGAWriter;
 
@@ -392,7 +393,7 @@ public class Screenshot {
 
   private static void checkExtABGR() {
     GL2 gl = GLUgl2.getCurrentGL2();
-    if (!gl.isExtensionAvailable("GL_EXT_abgr")) {
+    if (!gl.isExtensionAvailable(GLExtensions.EXT_abgr)) {
       throw new IllegalArgumentException("Saving alpha channel requires GL_EXT_abgr");
     }
   } 
diff --git a/src/jogl/classes/com/jogamp/opengl/util/awt/TextRenderer.java b/src/jogl/classes/com/jogamp/opengl/util/awt/TextRenderer.java
index 622ee1b79..1735fcddd 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/awt/TextRenderer.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/awt/TextRenderer.java
@@ -41,6 +41,7 @@ package com.jogamp.opengl.util.awt;
 
 import com.jogamp.common.nio.Buffers;
 
+import com.jogamp.opengl.GLExtensions;
 import com.jogamp.opengl.util.*;
 import com.jogamp.opengl.util.packrect.*;
 import com.jogamp.opengl.util.texture.*;
@@ -1976,7 +1977,7 @@ public class TextRenderer {
 
     private final boolean is15Available(GL gl) {
         if (!checkFor_isExtensionAvailable_GL_VERSION_1_5) {
-            isExtensionAvailable_GL_VERSION_1_5 = gl.isExtensionAvailable("GL_VERSION_1_5");
+            isExtensionAvailable_GL_VERSION_1_5 = gl.isExtensionAvailable(GLExtensions.VERSION_1_5);
             checkFor_isExtensionAvailable_GL_VERSION_1_5 = true;
         }
         return isExtensionAvailable_GL_VERSION_1_5;
diff --git a/src/jogl/classes/com/jogamp/opengl/util/texture/Texture.java b/src/jogl/classes/com/jogamp/opengl/util/texture/Texture.java
index 49d4add5f..e7bf87a36 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/texture/Texture.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/texture/Texture.java
@@ -44,6 +44,7 @@ import javax.media.nativewindow.NativeWindowFactory;
 
 import jogamp.opengl.*;
 
+import com.jogamp.opengl.GLExtensions;
 import com.jogamp.opengl.util.texture.spi.*;
 
 /**
@@ -262,8 +263,8 @@ public class Texture {
      *
      * See the <a href="#perftips">performance tips</a> above for hints
      * on how to maximize performance when using many Texture objects.
-     * @param gl TODO
-     *
+     * 
+     * @param gl the current GL context
      * @throws GLException if no OpenGL context was current or if any
      * OpenGL-related errors occurred
      */
@@ -448,12 +449,12 @@ public class Texture {
 
         // See whether we have automatic mipmap generation support
         boolean haveAutoMipmapGeneration =
-            (gl.isExtensionAvailable("GL_VERSION_1_4") ||
-             gl.isExtensionAvailable("GL_SGIS_generate_mipmap"));
+            (gl.isExtensionAvailable(GLExtensions.VERSION_1_4) ||
+             gl.isExtensionAvailable(GLExtensions.SGIS_generate_mipmap));
 
         // Indicate to the TextureData what functionality is available
-        data.setHaveEXTABGR(gl.isExtensionAvailable("GL_EXT_abgr"));
-        data.setHaveGL12(gl.isExtensionAvailable("GL_VERSION_1_2"));
+        data.setHaveEXTABGR(gl.isExtensionAvailable(GLExtensions.EXT_abgr));
+        data.setHaveGL12(gl.isExtensionAvailable(GLExtensions.VERSION_1_2));
 
         // Indicates whether both width and height are power of two
         boolean isPOT = isPowerOfTwo(imgWidth) && isPowerOfTwo(imgHeight);
@@ -646,7 +647,7 @@ public class Texture {
 
         int minFilter = (data.getMipmap() ? GL.GL_LINEAR_MIPMAP_LINEAR : GL.GL_LINEAR);
         int magFilter = GL.GL_LINEAR;
-        int wrapMode = (gl.isExtensionAvailable("GL_VERSION_1_2") || !gl.isGL2()) ? GL.GL_CLAMP_TO_EDGE : GL2.GL_CLAMP;
+        int wrapMode = (gl.isExtensionAvailable(GLExtensions.VERSION_1_2) || !gl.isGL2()) ? GL.GL_CLAMP_TO_EDGE : GL2.GL_CLAMP;
 
         // REMIND: figure out what to do for GL_TEXTURE_RECTANGLE_ARB
         if (texTarget != GL2.GL_TEXTURE_RECTANGLE_ARB) {
@@ -925,8 +926,8 @@ public class Texture {
     private void updateSubImageImpl(GL gl, TextureData data, int newTarget, int mipmapLevel,
                                     int dstx, int dsty,
                                     int srcx, int srcy, int width, int height) throws GLException {
-        data.setHaveEXTABGR(gl.isExtensionAvailable("GL_EXT_abgr"));
-        data.setHaveGL12(gl.isExtensionAvailable("GL_VERSION_1_2"));
+        data.setHaveEXTABGR(gl.isExtensionAvailable(GLExtensions.EXT_abgr));
+        data.setHaveGL12(gl.isExtensionAvailable(GLExtensions.VERSION_1_2));
 
         Buffer buffer = data.getBuffer();
         if (buffer == null && data.getMipmapData() == null) {
@@ -1044,8 +1045,8 @@ public class Texture {
             case GL.GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
             case GL.GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
             case GL.GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
-                if (!gl.isExtensionAvailable("GL_EXT_texture_compression_s3tc") &&
-                    !gl.isExtensionAvailable("GL_NV_texture_compression_vtc")) {
+                if (!gl.isExtensionAvailable(GLExtensions.EXT_texture_compression_s3tc) &&
+                    !gl.isExtensionAvailable(GLExtensions.NV_texture_compression_vtc)) {
                     throw new GLException("DXTn compressed textures not supported by this graphics card");
                 }
                 break;
@@ -1081,7 +1082,7 @@ public class Texture {
     private static boolean haveTexRect(GL gl) {
         return (!disableTexRect &&
                 TextureIO.isTexRectEnabled() &&
-                gl.isExtensionAvailable("GL_ARB_texture_rectangle"));
+                gl.isExtensionAvailable(GLExtensions.ARB_texture_rectangle));
     }
 
     private static boolean preferTexRect(GL gl) {
diff --git a/src/jogl/classes/com/jogamp/opengl/util/texture/TextureIO.java b/src/jogl/classes/com/jogamp/opengl/util/texture/TextureIO.java
index ca97cdc4b..b878c6002 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/texture/TextureIO.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/texture/TextureIO.java
@@ -155,6 +155,14 @@ public class TextureIO {
         file. */
     public static final String TIFF    = "tiff";
 
+    /** Constant which can be used as a file suffix to indicate a PAM
+        file, NetPbm magic 7 - binary RGB and RGBA. Write support only. */
+    public static final String PAM     = "pam";
+    
+    /** Constant which can be used as a file suffix to indicate a PAM
+        file, NetPbm magic 6 - binary RGB. Write support only. */
+    public static final String PPM     = "ppm";
+    
     private static final boolean DEBUG = Debug.debug("TextureIO");
 
     // For manually disabling the use of the texture rectangle
diff --git a/src/jogl/classes/com/jogamp/opengl/util/texture/TextureSequence.java b/src/jogl/classes/com/jogamp/opengl/util/texture/TextureSequence.java
index 5ee2104a3..6b41c0bc8 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/texture/TextureSequence.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/texture/TextureSequence.java
@@ -102,7 +102,6 @@ import javax.media.opengl.GL;
  */
 public interface TextureSequence {
     public static final String GL_OES_EGL_image_external_Required_Prelude = "#extension GL_OES_EGL_image_external : enable\n";
-    public static final String GL_OES_EGL_image_external = "GL_OES_EGL_image_external";
     public static final String samplerExternalOES = "samplerExternalOES";
     public static final String sampler2D = "sampler2D";
     
diff --git a/src/jogl/classes/com/jogamp/opengl/util/texture/spi/NetPbmTextureWriter.java b/src/jogl/classes/com/jogamp/opengl/util/texture/spi/NetPbmTextureWriter.java
index c2b131b97..cd42a1157 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/texture/spi/NetPbmTextureWriter.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/texture/spi/NetPbmTextureWriter.java
@@ -77,8 +77,10 @@ public class NetPbmTextureWriter implements TextureWriter {
 
     public int getMagic() { return magic; }
 
-    public static final String PPM     = "ppm";
-    public static final String PAM     = "pam";
+    /** @see TextureIO#PPM */
+    public static final String PPM     = TextureIO.PPM;
+    /** @see TextureIO#PAM */
+    public static final String PAM     = TextureIO.PAM;
 
     public String getSuffix() { return (magic==6)?PPM:PAM; }