GLArrayData*: Shorten methods (*API Change*), use proper constructor and finalize immutables, add growthFactor (default golden ratio 1.618), add getCapacity*() and printStats(..)

The growthFactor becomes essential for better growth behavior and can be set via setGrowthFactor().

The other changes were merely to clean up the GLArrayData interface and its 4 implementations.

Not great to change its API, but one name was misleading ['getComponentCount' -> 'getCompsPerEleme'],
so overall .. readability is enhanced.

Motivation for this change was the performance analysis and improvement of our Graph Curve Renderer.

4 files changed, 234 insertions, 208 deletions

diff --git a/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataClient.java b/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataClient.java
index 542da4bf1..e790194ca 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataClient.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataClient.java
@@ -48,6 +48,8 @@ import com.jogamp.opengl.util.glsl.ShaderState;
 
 
 public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayDataEditable {
+  /** Default growth factor using the golden ratio 1.618 */
+  public static final float DEFAULT_GROWTH_FACTOR = 1.618f;
 
   /**
    * Create a client side buffer object, using a predefined fixed function array index
@@ -72,10 +74,8 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
   public static GLArrayDataClient createFixed(final int index, final int comps, final int dataType, final boolean normalized, final int initialElementCount)
     throws GLException
   {
-      final GLArrayDataClient adc = new GLArrayDataClient();
-      final GLArrayHandler glArrayHandler = new GLFixedArrayHandler(adc);
-      adc.init(null, index, comps, dataType, normalized, 0, null, initialElementCount, 0 /* mappedElementCount */, false, glArrayHandler, 0, 0, 0, 0, false);
-      return adc;
+      return new GLArrayDataClient(null, index, comps, dataType, normalized, 0, null, initialElementCount, DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                   false, GLFixedArrayHandler.class, 0, 0, 0, 0, false);
   }
 
   /**
@@ -103,10 +103,8 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
                                               final Buffer buffer)
     throws GLException
   {
-      final GLArrayDataClient adc = new GLArrayDataClient();
-      final GLArrayHandler glArrayHandler = new GLFixedArrayHandler(adc);
-      adc.init(null, index, comps, dataType, normalized, stride, buffer, comps*comps, 0 /* mappedElementCount */, false, glArrayHandler, 0, 0, 0, 0, false);
-      return adc;
+      return new GLArrayDataClient(null, index, comps, dataType, normalized, stride, buffer, comps*comps, DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                   false, GLFixedArrayHandler.class, 0, 0, 0, 0, false);
   }
 
   /**
@@ -122,10 +120,8 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
                                              final int dataType, final boolean normalized, final int initialElementCount)
     throws GLException
   {
-      final GLArrayDataClient adc = new GLArrayDataClient();
-      final GLArrayHandler glArrayHandler = new GLSLArrayHandler(adc);
-      adc.init(name, -1, comps, dataType, normalized, 0, null, initialElementCount, 0 /* mappedElementCount */, true, glArrayHandler, 0, 0, 0, 0, true);
-      return adc;
+      return new GLArrayDataClient(name, -1, comps, dataType, normalized, 0, null, initialElementCount, DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                   true, GLSLArrayHandler.class, 0, 0, 0, 0, true);
   }
 
   /**
@@ -142,10 +138,8 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
                                              final int dataType, final boolean normalized, final int stride, final Buffer buffer)
     throws GLException
   {
-      final GLArrayDataClient adc = new GLArrayDataClient();
-      final GLArrayHandler glArrayHandler = new GLSLArrayHandler(adc);
-      adc.init(name, -1, comps, dataType, normalized, stride, buffer, comps*comps, 0 /* mappedElementCount */, true, glArrayHandler, 0, 0, 0, 0, true);
-      return adc;
+      return new GLArrayDataClient(name, -1, comps, dataType, normalized, stride, buffer, comps*comps, DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                   true, GLSLArrayHandler.class, 0, 0, 0, 0, true);
   }
 
   @Override
@@ -183,14 +177,14 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
 
   @Override
   public void destroy(final GL gl) {
-    reset(gl);
+    clear(gl);
     super.destroy(gl);
   }
 
   @Override
-  public void reset(final GL gl) {
-    enableBuffer(gl, false);
-    reset();
+  public void clear(final GL gl) {
+    seal(gl, false);
+    clear();
   }
 
   @Override
@@ -232,7 +226,7 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
   //
 
   @Override
-  public void reset() {
+  public void clear() {
     if( buffer != null ) {
         buffer.clear();
     }
@@ -334,7 +328,7 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
                        ", usesShaderState "+(null!=shaderState)+
                        ", dataType 0x"+Integer.toHexString(componentType)+
                        ", bufferClazz "+componentClazz+
-                       ", elements "+getElementCount()+
+                       ", elements "+getElemCount()+
                        ", components "+componentsPerElement+
                        ", stride "+strideB+"b "+strideL+"c"+
                        ", mappedElementCount "+mappedElementCount+
@@ -349,20 +343,27 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
 
   // non public matters
 
-  protected final boolean growBufferIfNecessary(final int spareComponents) {
+  private final boolean growBufferIfNecessary(final int spareComponents) {
     if( buffer==null || buffer.remaining()<spareComponents ) {
         if( 0 != mappedElementCount ) {
             throw new GLException("Mapped buffer can't grow. Insufficient storage size: Needed "+spareComponents+" components, "+
                                   "mappedElementCount "+mappedElementCount+
                                   ", has mapped buffer "+buffer+"; "+this);
         }
-        growBuffer(Math.max(initialElementCount, (spareComponents+componentsPerElement-1)/componentsPerElement));
+        final int required_elems = ( spareComponents + componentsPerElement - 1 ) / componentsPerElement;
+        if( null == buffer ) {
+            growBuffer( Math.max( initialElementCount, required_elems ) );
+        } else {
+            final int add_comps = (int)( buffer.capacity() * ( growthFactor - 1.0f ) + 0.5f );
+            final int add_elems = ( add_comps + componentsPerElement - 1 ) / componentsPerElement;
+            growBuffer( Math.max( add_elems, required_elems ) );
+        }
         return true;
     }
     return false;
   }
 
-  protected final void growBuffer(int additionalElements) {
+  private final void growBuffer(int additionalElements) {
     if(!alive || sealed) {
        throw new GLException("Invalid state: "+this);
     }
@@ -424,20 +425,32 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
     }
   }
 
-  protected void init(final String name, final int index, final int comps, final int dataType, final boolean normalized, final int stride, final Buffer data,
-                      final int initialElementCount, final int mappedElementCount, final boolean isVertexAttribute,
-                      final GLArrayHandler handler, final int vboName, final long vboOffset, final int vboUsage, final int vboTarget, final boolean usesGLSL)
+  protected GLArrayDataClient(final String name, final int index, final int comps, final int dataType, final boolean normalized, final int stride, final Buffer data,
+                              final int initialElementCount, final float growthFactor,
+                              final int mappedElementCount, final boolean isVertexAttribute,
+                              final Class<? extends GLArrayHandler> handlerClass,
+                              final int vboName, final long vboOffset, final int vboUsage, final int vboTarget, final boolean usesGLSL)
     throws GLException
   {
-    super.init(name, index, comps, dataType, normalized, stride, data, mappedElementCount,
-               isVertexAttribute, vboName, vboOffset, vboUsage, vboTarget);
+    super(name, index, comps, dataType, normalized, stride, data, mappedElementCount,
+          isVertexAttribute, vboName, vboOffset, vboUsage, vboTarget);
 
     if( 0<mappedElementCount && 0<initialElementCount ) { // null!=buffer case validated in super.init(..)
         throw new IllegalArgumentException("mappedElementCount:="+mappedElementCount+" specified, but passing non zero initialElementSize");
     }
+
+    // immutable types
     this.initialElementCount = initialElementCount;
-    this.glArrayHandler = handler;
+    this.growthFactor = growthFactor;
+    try {
+        final Constructor<? extends GLArrayHandler> ctor = handlerClass.getConstructor(GLArrayDataEditable.class);
+        this.glArrayHandler = ctor.newInstance(this);
+    } catch (final Exception e) {
+        throw new RuntimeException("Could not ctor "+handlerClass.getName()+"("+this.getClass().getName()+")", e);
+    }
     this.usesGLSL = usesGLSL;
+
+    // mutable types
     this.sealed=false;
     this.bufferEnabled=false;
     this.enableBufferAlways=false;
@@ -448,8 +461,6 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
     }
   }
 
-  private boolean isValidated = false;
-
   protected void init_vbo(final GL gl) {
       if(!isValidated ) {
           isValidated = true;
@@ -457,8 +468,6 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
       }
   }
 
-  protected GLArrayDataClient() { }
-
   /**
    * Copy Constructor
    * <p>
@@ -470,11 +479,8 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
    */
   public GLArrayDataClient(final GLArrayDataClient src) {
     super(src);
-    this.isValidated = src.isValidated;
-    this.sealed = src.sealed;
-    this.bufferEnabled = src.bufferEnabled;
-    this.bufferWritten = src.bufferWritten;
-    this.enableBufferAlways = src.enableBufferAlways;
+
+    // immutable types
     this.initialElementCount = src.initialElementCount;
     if( null != src.glArrayHandler ) {
         final Class<? extends GLArrayHandler> clazz = src.glArrayHandler.getClass();
@@ -488,18 +494,55 @@ public class GLArrayDataClient extends GLArrayDataWrapper implements GLArrayData
         this.glArrayHandler = null;
     }
     this.usesGLSL = src.usesGLSL;
+
+    // mutable types
+    this.growthFactor = src.growthFactor;
+    this.isValidated = src.isValidated;
+    this.sealed = src.sealed;
+    this.bufferEnabled = src.bufferEnabled;
+    this.bufferWritten = src.bufferWritten;
+    this.enableBufferAlways = src.enableBufferAlways;
     this.shaderState = src.shaderState;
   }
 
+  /**
+   * Returns this buffer's growth factor.
+   * <p>
+   * Default is {@link #DEFAULT_GROWTH_FACTOR}, i.e. the golden ratio 1.618.
+   * </p>
+   * @see #setGrowthFactor(float)
+   * @see #DEFAULT_GROWTH_FACTOR
+   */
+  public float getGrowthFactor() { return growthFactor; }
+
+  /**
+   * Sets a new growth factor for this buffer.
+   * <p>
+   * Default is {@link #DEFAULT_GROWTH_FACTOR}, i.e. the golden ratio 1.618.
+   * </p>
+   * @param v new growth factor, which must be >= 1.1, i.e. 10%
+   * @throws IllegalArgumentException if growth factor is < 1.1
+   * @see #getGrowthFactor()
+   * @see #DEFAULT_GROWTH_FACTOR
+   */
+  public void setGrowthFactor(final float v) {
+      if( v < 1.1f ) {
+          throw new IllegalArgumentException("New growth factor must be > 1.1 but is "+v);
+      }
+      growthFactor = v;
+  }
+
+  protected final int initialElementCount;
+  protected final GLArrayHandler glArrayHandler;
+  protected final boolean usesGLSL;
+
+  protected float growthFactor;
+  private boolean isValidated = false;
   protected boolean sealed;
   protected boolean bufferEnabled;
   protected boolean bufferWritten;
   protected boolean enableBufferAlways;
 
-  protected int initialElementCount;
-
-  protected GLArrayHandler glArrayHandler;
-  protected boolean usesGLSL;
   protected ShaderState shaderState;
 
 }
diff --git a/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataEditable.java b/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataEditable.java
index 7524fe1d1..50bcf7c5b 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataEditable.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataEditable.java
@@ -34,7 +34,16 @@ public interface GLArrayDataEditable extends GLArrayData {
     @Override
     public void destroy(GL gl);
 
-    public void reset(GL gl);
+    /**
+     * Clears this buffer.
+     * <p>
+     * Implementation must call {@link #seal(GL, boolean) seal(gl, false)} and {@link #clear()},
+     * i.e. turns-off the GL buffer and then clearing it.
+     * </p>
+     * @see #seal(GL, boolean)
+     * @see #clear()
+     */
+    public void clear(GL gl);
 
     /**
      * Convenience method calling {@link #seal(boolean)} and {@link #enableBuffer(GL, boolean)}.
@@ -105,7 +114,11 @@ public interface GLArrayDataEditable extends GLArrayData {
     // Data modification ..
     //
 
-    public void reset();
+    /**
+     * Clears this buffer and resets states accordingly.
+     * @see #clear(GL)
+     */
+    public void clear();
 
     /**
      * <p>If <i>seal</i> is true, it
diff --git a/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataServer.java b/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataServer.java
index 6b7c31d13..9c803d36e 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataServer.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataServer.java
@@ -85,11 +85,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                               final Buffer buffer, final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLFixedArrayHandler(ads);
-    ads.init(null, index, compsPerElement, dataType, normalized, stride, buffer, buffer.limit(), 0 /* mappedElementCount */, false,
-             glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
-    return ads;
+    return new GLArrayDataServer(null, index, compsPerElement, dataType, normalized, stride, buffer, buffer.limit(), DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                 false, GLFixedArrayHandler.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
   }
 
   /**
@@ -117,11 +114,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                               final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLFixedArrayHandler(ads);
-    ads.init(null, index, compsPerElement, dataType, normalized, 0, null, initialElementCount, 0 /* mappedElementCount */, false,
-             glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
-    return ads;
+    return new GLArrayDataServer(null, index, compsPerElement, dataType, normalized, 0, null, initialElementCount, DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                 false, GLFixedArrayHandler.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
   }
 
   /**
@@ -138,11 +132,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                              final int dataType, final boolean normalized, final int initialElementCount, final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLSLArrayHandler(ads);
-    ads.init(name, -1, compsPerElement, dataType, normalized, 0, null, initialElementCount,
-             0 /* mappedElementCount */, true, glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
-    return ads;
+    return new GLArrayDataServer(name, -1, compsPerElement, dataType, normalized, 0, null, initialElementCount,
+                                 DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */, true, GLSLArrayHandler.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
   }
 
   /**
@@ -159,10 +150,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                                    final int dataType, final boolean normalized, final int mappedElementCount, final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLSLArrayHandler(ads);
-    ads.init(name, -1, compsPerElement, dataType, normalized, 0, null, 0 /* initialElementCount */,
-             mappedElementCount, true, glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
+    final GLArrayDataServer ads = new GLArrayDataServer(name, -1, compsPerElement, dataType, normalized, 0, null, 0 /* initialElementCount */,
+                                                        DEFAULT_GROWTH_FACTOR, mappedElementCount, true, GLSLArrayHandler.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
     ads.seal(true);
     return ads;
   }
@@ -183,11 +172,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                              final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLSLArrayHandler(ads);
-    ads.init(name, -1, compsPerElement, dataType, normalized, stride, buffer, buffer.limit(), 0 /* mappedElementCount */, true,
-             glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
-    return ads;
+    return new GLArrayDataServer(name, -1, compsPerElement, dataType, normalized, stride, buffer, buffer.limit(), DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                 true, GLSLArrayHandler.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
   }
 
   /**
@@ -207,11 +193,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                              final Buffer buffer, final int vboUsage, final int vboTarget)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLDataArrayHandler(ads);
-    ads.init(null, -1, compsPerElement, dataType, false, stride, buffer, buffer.limit(), 0 /* mappedElementCount */, false,
-             glArrayHandler, 0, 0, vboUsage, vboTarget, false);
-    return ads;
+    return new GLArrayDataServer(null, -1, compsPerElement, dataType, false, stride, buffer, buffer.limit(), DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                 false, GLDataArrayHandler.class, 0, 0, vboUsage, vboTarget, false);
   }
 
   /**
@@ -229,11 +212,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                              final int vboUsage, final int vboTarget)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLDataArrayHandler(ads);
-    ads.init(null, -1, compsPerElement, dataType, false, 0, null, initialElementCount, 0 /* mappedElementCount */, false,
-             glArrayHandler, 0, 0, vboUsage, vboTarget, false);
-    return ads;
+    return new GLArrayDataServer(null, -1, compsPerElement, dataType, false, 0, null, initialElementCount, DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                 false, GLDataArrayHandler.class, 0, 0, vboUsage, vboTarget, false);
   }
 
   /**
@@ -253,11 +233,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                                    final int vboUsage, final int vboTarget)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLDataArrayHandler(ads);
-    ads.init(null, -1, compsPerElement, dataType, false, 0, null, 0 /* initialElementCount */, mappedElementCount, false,
-             glArrayHandler, 0, 0, vboUsage, vboTarget, false);
-    return ads;
+    return new GLArrayDataServer(null, -1, compsPerElement, dataType, false, 0, null, 0 /* initialElementCount */, DEFAULT_GROWTH_FACTOR, mappedElementCount,
+                                 false, GLDataArrayHandler.class, 0, 0, vboUsage, vboTarget, false);
   }
 
   /**
@@ -275,11 +252,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                               final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLArrayHandlerInterleaved(ads);
-    ads.init(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, false, 0, null, initialElementCount, 0 /* mappedElementCount */, false,
-             glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
-    return ads;
+    return new GLArrayDataServer(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, false, 0, null, initialElementCount, DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                 false, GLArrayHandlerInterleaved.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
   }
 
   /**
@@ -297,10 +271,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                                                final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLArrayHandlerInterleaved(ads);
-    ads.init(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, false, 0, null, 0 /* initialElementCount */, mappedElementCount, false,
-             glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
+    final GLArrayDataServer ads = new GLArrayDataServer(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, false, 0, null, 0 /* initialElementCount */, DEFAULT_GROWTH_FACTOR, mappedElementCount,
+                                                        false, GLArrayHandlerInterleaved.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
     ads.seal(true);
     return ads;
   }
@@ -321,11 +293,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                               final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLArrayHandlerInterleaved(ads);
-    ads.init(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, normalized, stride, buffer, buffer.limit(), 0 /* mappedElementCount */, false,
-             glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
-    return ads;
+    return new GLArrayDataServer(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, normalized, stride, buffer, buffer.limit(), DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                 false, GLArrayHandlerInterleaved.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, false);
   }
 
   /**
@@ -343,28 +312,28 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
    * @param vboTarget {@link GL#GL_ARRAY_BUFFER} or {@link GL#GL_ELEMENT_ARRAY_BUFFER}
    */
   public GLArrayData addFixedSubArray(final int index, final int comps, final int vboTarget) {
-      if(interleavedOffset >= getComponentCount() * getComponentSizeInBytes()) {
-          final int iOffC = interleavedOffset / getComponentSizeInBytes();
-          throw new GLException("Interleaved offset > total components ("+iOffC+" > "+getComponentCount()+")");
+      if(interleavedOffset >= getCompsPerElem() * getBytesPerComp()) {
+          final int iOffC = interleavedOffset / getBytesPerComp();
+          throw new GLException("Interleaved offset > total components ("+iOffC+" > "+getCompsPerElem()+")");
       }
       if(usesGLSL) {
           throw new GLException("buffer uses GLSL");
       }
-      final int subStrideB = ( 0 == getStride() ) ? getComponentCount() * getComponentSizeInBytes() : getStride();
+      final int subStrideB = ( 0 == getStride() ) ? getCompsPerElem() * getBytesPerComp() : getStride();
       final GLArrayDataWrapper ad;
       if( 0 < mappedElementCount ) {
           ad = GLArrayDataWrapper.createFixed(
-                  index, comps, getComponentType(),
+                  index, comps, getCompType(),
                   getNormalized(), subStrideB, mappedElementCount,
                   getVBOName(), interleavedOffset, getVBOUsage(), vboTarget);
       } else {
           ad = GLArrayDataWrapper.createFixed(
-                  index, comps, getComponentType(),
+                  index, comps, getCompType(),
                   getNormalized(), subStrideB, getBuffer(),
                   getVBOName(), interleavedOffset, getVBOUsage(), vboTarget);
       }
       ad.setVBOEnabled(isVBO());
-      interleavedOffset += comps * getComponentSizeInBytes();
+      interleavedOffset += comps * getBytesPerComp();
       if(GL.GL_ARRAY_BUFFER == vboTarget) {
           glArrayHandler.addSubHandler(new GLFixedArrayHandlerFlat(ad));
       }
@@ -386,11 +355,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                                         final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLSLArrayHandlerInterleaved(ads);
-    ads.init(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, normalized, 0, null, initialElementCount, 0 /* mappedElementCount */, false,
-             glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
-    return ads;
+    return new GLArrayDataServer(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, normalized, 0, null, initialElementCount, DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                 false, GLSLArrayHandlerInterleaved.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
   }
 
   /**
@@ -407,10 +373,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
   public static GLArrayDataServer createGLSLInterleavedMapped(final int compsPerElement, final int dataType, final boolean normalized, final int mappedElementCount, final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLSLArrayHandlerInterleaved(ads);
-    ads.init(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, normalized, 0, null, 0 /* initialElementCount */, mappedElementCount, false,
-             glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
+    final GLArrayDataServer ads = new GLArrayDataServer(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, normalized, 0, null, 0 /* initialElementCount */, DEFAULT_GROWTH_FACTOR, mappedElementCount,
+                                                  false, GLSLArrayHandlerInterleaved.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
     ads.seal(true);
     return ads;
   }
@@ -431,11 +395,8 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                                                         final int vboUsage)
     throws GLException
   {
-    final GLArrayDataServer ads = new GLArrayDataServer();
-    final GLArrayHandler glArrayHandler = new GLSLArrayHandlerInterleaved(ads);
-    ads.init(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, normalized, stride, buffer, buffer.limit(), 0 /* mappedElementCount */, false,
-             glArrayHandler, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
-    return ads;
+    return new GLArrayDataServer(GLPointerFuncUtil.mgl_InterleaveArray, -1, compsPerElement, dataType, normalized, stride, buffer, buffer.limit(), DEFAULT_GROWTH_FACTOR, 0 /* mappedElementCount */,
+                                 false, GLSLArrayHandlerInterleaved.class, 0, 0, vboUsage, GL.GL_ARRAY_BUFFER, true);
   }
 
   /**
@@ -452,28 +413,28 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
    * @param vboTarget {@link GL#GL_ARRAY_BUFFER} or {@link GL#GL_ELEMENT_ARRAY_BUFFER}
    */
   public GLArrayData addGLSLSubArray(final String name, final int comps, final int vboTarget) {
-      if(interleavedOffset >= getComponentCount() * getComponentSizeInBytes()) {
-          final int iOffC = interleavedOffset / getComponentSizeInBytes();
-          throw new GLException("Interleaved offset > total components ("+iOffC+" > "+getComponentCount()+")");
+      if(interleavedOffset >= getCompsPerElem() * getBytesPerComp()) {
+          final int iOffC = interleavedOffset / getBytesPerComp();
+          throw new GLException("Interleaved offset > total components ("+iOffC+" > "+getCompsPerElem()+")");
       }
       if(!usesGLSL) {
           throw new GLException("buffer uses fixed function");
       }
-      final int subStrideB = ( 0 == getStride() ) ? getComponentCount() * getComponentSizeInBytes() : getStride();
+      final int subStrideB = ( 0 == getStride() ) ? getCompsPerElem() * getBytesPerComp() : getStride();
       final GLArrayDataWrapper ad;
       if( 0 < mappedElementCount ) {
           ad = GLArrayDataWrapper.createGLSL(
-                  name, comps, getComponentType(),
+                  name, comps, getCompType(),
                   getNormalized(), subStrideB, mappedElementCount,
                   getVBOName(), interleavedOffset, getVBOUsage(), vboTarget);
       } else {
           ad = GLArrayDataWrapper.createGLSL(
-                  name, comps, getComponentType(),
+                  name, comps, getCompType(),
                   getNormalized(), subStrideB, getBuffer(),
                   getVBOName(), interleavedOffset, getVBOUsage(), vboTarget);
       }
       ad.setVBOEnabled(isVBO());
-      interleavedOffset += comps * getComponentSizeInBytes();
+      interleavedOffset += comps * getBytesPerComp();
       if(GL.GL_ARRAY_BUFFER == vboTarget) {
           glArrayHandler.addSubHandler(new GLSLArrayHandlerFlat(ad));
       }
@@ -597,7 +558,7 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
                        ", usesShaderState "+(null!=shaderState)+
                        ", dataType 0x"+Integer.toHexString(componentType)+
                        ", bufferClazz "+componentClazz+
-                       ", elements "+getElementCount()+
+                       ", elements "+getElemCount()+
                        ", components "+componentsPerElement+
                        ", stride "+strideB+"b "+strideL+"c"+
                        ", initialElementCount "+initialElementCount+
@@ -620,15 +581,14 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
   // non public matters ..
   //
 
-  @Override
-  protected void init(final String name, final int index, final int comps, final int dataType, final boolean normalized,
-                      final int stride, final Buffer data, final int initialElementCount, final int mappedElementCount,
-                      final boolean isVertexAttribute,
-                      final GLArrayHandler glArrayHandler, final int vboName, final long vboOffset, final int vboUsage, final int vboTarget, final boolean usesGLSL)
+  protected GLArrayDataServer(final String name, final int index, final int comps, final int dataType, final boolean normalized,
+                              final int stride, final Buffer data, final int initialElementCount, final float growthFactor,
+                              final int mappedElementCount, final boolean isVertexAttribute,
+                              final Class<? extends GLArrayHandler> handlerClass, final int vboName, final long vboOffset, final int vboUsage, final int vboTarget, final boolean usesGLSL)
     throws GLException
   {
-    super.init(name, index, comps, dataType, normalized, stride, data, initialElementCount, mappedElementCount, isVertexAttribute,
-               glArrayHandler, vboName, vboOffset, vboUsage, vboTarget, usesGLSL);
+    super(name, index, comps, dataType, normalized, stride, data, initialElementCount, growthFactor, mappedElementCount,
+          isVertexAttribute, handlerClass, vboName, vboOffset, vboUsage, vboTarget, usesGLSL);
 
     vboEnabled=true;
   }
@@ -646,8 +606,6 @@ public class GLArrayDataServer extends GLArrayDataClient implements GLArrayDataE
     }
   }
 
-  protected GLArrayDataServer() { }
-
   /**
    * Copy Constructor
    * <p>
diff --git a/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataWrapper.java b/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataWrapper.java
index 3f759c6d8..ae19d788f 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataWrapper.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/GLArrayDataWrapper.java
@@ -28,6 +28,7 @@
 
 package com.jogamp.opengl.util;
 
+import java.io.PrintStream;
 import java.nio.Buffer;
 import java.nio.ByteBuffer;
 import java.nio.FloatBuffer;
@@ -35,7 +36,6 @@ import java.nio.IntBuffer;
 import java.nio.ShortBuffer;
 
 import com.jogamp.opengl.GL;
-import com.jogamp.opengl.GL2ES1;
 import com.jogamp.opengl.GL2ES2;
 import com.jogamp.opengl.GLArrayData;
 import com.jogamp.opengl.GLException;
@@ -70,10 +70,8 @@ public class GLArrayDataWrapper implements GLArrayData {
                                                final Buffer buffer, final int vboName, final long vboOffset, final int vboUsage, final int vboTarget)
     throws GLException
   {
-      final GLArrayDataWrapper adc = new GLArrayDataWrapper();
-      adc.init(null, index, comps, dataType, normalized, stride, buffer, 0 /* mappedElementCount */,
-               false, vboName, vboOffset, vboUsage, vboTarget);
-      return adc;
+      return new GLArrayDataWrapper(null, index, comps, dataType, normalized, stride, buffer, 0 /* mappedElementCount */,
+                                    false, vboName, vboOffset, vboUsage, vboTarget);
   }
 
   /**
@@ -97,10 +95,8 @@ public class GLArrayDataWrapper implements GLArrayData {
                                                final int mappedElementCount, final int vboName, final long vboOffset, final int vboUsage, final int vboTarget)
     throws GLException
   {
-      final GLArrayDataWrapper adc = new GLArrayDataWrapper();
-      adc.init(null, index, comps, dataType, normalized, stride, null, mappedElementCount,
-               false, vboName, vboOffset, vboUsage, vboTarget);
-      return adc;
+      return new GLArrayDataWrapper(null, index, comps, dataType, normalized, stride, null, mappedElementCount,
+                                    false, vboName, vboOffset, vboUsage, vboTarget);
   }
 
   /**
@@ -123,10 +119,8 @@ public class GLArrayDataWrapper implements GLArrayData {
                                              final Buffer buffer, final int vboName, final long vboOffset, final int vboUsage, final int vboTarget)
     throws GLException
   {
-      final GLArrayDataWrapper adc = new GLArrayDataWrapper();
-      adc.init(name, -1, comps, dataType, normalized, stride, buffer, 0  /* mappedElementCount */,
-              true, vboName, vboOffset, vboUsage, vboTarget);
-      return adc;
+      return new GLArrayDataWrapper(name, -1, comps, dataType, normalized, stride, buffer, 0  /* mappedElementCount */,
+                                    true, vboName, vboOffset, vboUsage, vboTarget);
   }
 
   /**
@@ -149,10 +143,8 @@ public class GLArrayDataWrapper implements GLArrayData {
                                               final int mappedElementCount, final int vboName, final long vboOffset, final int vboUsage, final int vboTarget)
     throws GLException
   {
-      final GLArrayDataWrapper adc = new GLArrayDataWrapper();
-      adc.init(name, -1, comps, dataType, normalized, stride, null, mappedElementCount,
-              true, vboName, vboOffset, vboUsage, vboTarget);
-      return adc;
+      return new GLArrayDataWrapper(name, -1, comps, dataType, normalized, stride, null, mappedElementCount,
+                                    true, vboName, vboOffset, vboUsage, vboTarget);
   }
 
   /**
@@ -176,7 +168,7 @@ public class GLArrayDataWrapper implements GLArrayData {
         }
         return false;
     }
-    return glp.isValidArrayDataType(getIndex(), getComponentCount(), getComponentType(), isVertexAttribute(), throwException);
+    return glp.isValidArrayDataType(getIndex(), getCompsPerElem(), getCompType(), isVertexAttribute(), throwException);
   }
 
   @Override
@@ -235,21 +227,21 @@ public class GLArrayDataWrapper implements GLArrayData {
   public Buffer getBuffer() { return buffer; }
 
   @Override
-  public final int getComponentCount() { return componentsPerElement; }
+  public final int getCompsPerElem() { return componentsPerElement; }
 
   @Override
-  public final int getComponentType() { return componentType; }
+  public final int getCompType() { return componentType; }
 
   @Override
-  public final int getComponentSizeInBytes() { return componentByteSize; }
+  public final int getBytesPerComp() { return bytesPerComponent; }
 
   @Override
-  public final int getElementCount() {
+  public final int getElemCount() {
     if( 0 != mappedElementCount ) {
         return mappedElementCount;
     } else if( null != buffer ) {
         final int remainingComponents = ( 0 == buffer.position() ) ? buffer.limit() : buffer.position();
-        return ( remainingComponents * componentByteSize ) / strideB ;
+        return ( remainingComponents * bytesPerComponent ) / strideB ;
     } else {
         return 0;
     }
@@ -258,15 +250,29 @@ public class GLArrayDataWrapper implements GLArrayData {
   @Override
   public final int getSizeInBytes() {
     if( 0 != mappedElementCount ) {
-        return mappedElementCount * componentsPerElement * componentByteSize ;
+        return mappedElementCount * componentsPerElement * bytesPerComponent ;
     } else if( null != buffer ) {
-        return ( buffer.position()==0 ) ? ( buffer.limit() * componentByteSize ) : ( buffer.position() * componentByteSize ) ;
+        return ( buffer.position()==0 ) ? ( buffer.limit() * bytesPerComponent ) : ( buffer.position() * bytesPerComponent ) ;
     } else {
         return 0;
     }
   }
 
   @Override
+  public int getCapacityInBytes() {
+    if( null != buffer ) {
+        return buffer.capacity() * bytesPerComponent;
+    } else {
+        return 0;
+    }
+  }
+
+  @Override
+  public void printStats(final PrintStream out) {
+      out.printf("elements %,d, bytes %,d / %,d", getElemCount(), getSizeInBytes(), getCapacityInBytes());
+  }
+
+  @Override
   public final boolean getNormalized() { return normalized; }
 
   @Override
@@ -291,7 +297,7 @@ public class GLArrayDataWrapper implements GLArrayData {
                        ", isVertexAttribute "+isVertexAttribute+
                        ", dataType 0x"+Integer.toHexString(componentType)+
                        ", bufferClazz "+componentClazz+
-                       ", elements "+getElementCount()+
+                       ", elements "+getElemCount()+
                        ", components "+componentsPerElement+
                        ", stride "+strideB+"b "+strideL+"c"+
                        ", mappedElementCount "+mappedElementCount+
@@ -364,17 +370,14 @@ public class GLArrayDataWrapper implements GLArrayData {
       this.vboTarget = vboTarget;
   }
 
-  protected void init(final String name, final int index, final int componentsPerElement, final int componentType,
-                      final boolean normalized, final int stride, final Buffer data, final int mappedElementCount,
-                      final boolean isVertexAttribute, final int vboName, final long vboOffset, final int vboUsage, final int vboTarget)
+  protected GLArrayDataWrapper(final String name, final int index, final int componentsPerElement, final int componentType,
+                               final boolean normalized, final int stride, final Buffer data, final int mappedElementCount,
+                               final boolean isVertexAttribute, final int vboName, final long vboOffset, final int vboUsage, final int vboTarget)
     throws GLException
   {
     if( 0<mappedElementCount && null != data ) {
         throw new IllegalArgumentException("mappedElementCount:="+mappedElementCount+" specified, but passing non null buffer");
     }
-    this.isVertexAttribute = isVertexAttribute;
-    this.index = index;
-    this.location = -1;
     // We can't have any dependence on the FixedFuncUtil class here for build bootstrapping reasons
 
     if( GL.GL_ELEMENT_ARRAY_BUFFER == vboTarget ) {
@@ -389,15 +392,11 @@ public class GLArrayDataWrapper implements GLArrayData {
         throw new GLException("Invalid GPUBuffer target: 0x"+Integer.toHexString(vboTarget));
     }
 
+    // immutable types
     this.componentType = componentType;
     componentClazz = getBufferClass(componentType);
-    if( GLBuffers.isGLTypeFixedPoint(componentType) ) {
-        this.normalized = normalized;
-    } else {
-        this.normalized = false;
-    }
-    componentByteSize = GLBuffers.sizeOfGLType(componentType);
-    if(0 > componentByteSize) {
+    bytesPerComponent = GLBuffers.sizeOfGLType(componentType);
+    if(0 > bytesPerComponent) {
         throw new GLException("Given componentType not supported: "+componentType+":\n\t"+this);
     }
     if(0 >= componentsPerElement) {
@@ -405,19 +404,30 @@ public class GLArrayDataWrapper implements GLArrayData {
     }
     this.componentsPerElement = componentsPerElement;
 
-    if(0<stride && stride<componentsPerElement*componentByteSize) {
-        throw new GLException("stride ("+stride+") lower than component bytes, "+componentsPerElement+" * "+componentByteSize);
+    if(0<stride && stride<componentsPerElement*bytesPerComponent) {
+        throw new GLException("stride ("+stride+") lower than component bytes, "+componentsPerElement+" * "+bytesPerComponent);
     }
-    if(0<stride && stride%componentByteSize!=0) {
-        throw new GLException("stride ("+stride+") not a multiple of bpc "+componentByteSize);
+    if(0<stride && stride%bytesPerComponent!=0) {
+        throw new GLException("stride ("+stride+") not a multiple of bpc "+bytesPerComponent);
+    }
+    this.strideB=(0==stride)?componentsPerElement*bytesPerComponent:stride;
+    this.strideL=strideB/bytesPerComponent;
+
+    if( GLBuffers.isGLTypeFixedPoint(componentType) ) {
+        this.normalized = normalized;
+    } else {
+        this.normalized = false;
     }
-    this.buffer = data;
     this.mappedElementCount = mappedElementCount;
-    this.strideB=(0==stride)?componentsPerElement*componentByteSize:stride;
-    this.strideL=strideB/componentByteSize;
+    this.isVertexAttribute = isVertexAttribute;
+
+    // mutable types
+    this.index = index;
+    this.location = -1;
+    this.buffer = data;
     this.vboName= vboName;
-    this.vboEnabled= 0 != vboName ;
     this.vboOffset=vboOffset;
+    this.vboEnabled= 0 != vboName ;
 
     switch(vboUsage) {
         case 0: // nop
@@ -441,8 +451,6 @@ public class GLArrayDataWrapper implements GLArrayData {
     this.alive=true;
   }
 
-  protected GLArrayDataWrapper() { }
-
   /**
    * Copy Constructor
    * <p>
@@ -453,17 +461,22 @@ public class GLArrayDataWrapper implements GLArrayData {
    * </p>
    */
   public GLArrayDataWrapper(final GLArrayDataWrapper src) {
-    this.alive = src.alive;
-    this.index = src.index;
-    this.location = src.location;
-    this.name = src.name;
-    this.componentsPerElement = src.componentsPerElement;
+    // immutable types
     this.componentType = src.componentType;
     this.componentClazz = src.componentClazz;
-    this.componentByteSize = src.componentByteSize;
-    this.normalized = src.normalized;
+    this.bytesPerComponent = src.bytesPerComponent;
+    this.componentsPerElement = src.componentsPerElement;
     this.strideB = src.strideB;
     this.strideL = src.strideL;
+    this.normalized = src.normalized;
+    this.mappedElementCount = src.mappedElementCount;
+    this.isVertexAttribute = src.isVertexAttribute;
+
+    // mutable types
+    this.alive = src.alive;
+    this.index = src.index;
+    this.location = src.location;
+    this.name = src.name;
     if( null != src.buffer ) {
         if( src.buffer.position() == 0 ) {
             this.buffer = Buffers.slice(src.buffer);
@@ -473,33 +486,32 @@ public class GLArrayDataWrapper implements GLArrayData {
     } else {
         this.buffer = null;
     }
-    this.mappedElementCount = src.mappedElementCount;
-    this.isVertexAttribute = src.isVertexAttribute;
-    this.vboOffset = src.vboOffset;
     this.vboName = src.vboName;
+    this.vboOffset = src.vboOffset;
     this.vboEnabled = src.vboEnabled;
     this.vboUsage = src.vboUsage;
     this.vboTarget = src.vboTarget;
   }
 
+  protected final int componentType;
+  protected final Class<?> componentClazz;
+  protected final int bytesPerComponent;
+  protected final int componentsPerElement;
+  /** stride in bytes; strideB >= componentsPerElement * componentByteSize */
+  protected final int strideB;
+  /** stride in logical components */
+  protected final int strideL;
+  protected final boolean normalized;
+  protected final int mappedElementCount;
+  protected final boolean isVertexAttribute;
+
   protected boolean alive;
   protected int index;
   protected int location;
   protected String name;
-  protected int componentsPerElement;
-  protected int componentType;
-  protected Class<?> componentClazz;
-  protected int componentByteSize;
-  protected boolean normalized;
-  /** stride in bytes; strideB >= componentsPerElement * componentByteSize */
-  protected int strideB;
-  /** stride in logical components */
-  protected int strideL;
   protected Buffer buffer;
-  protected int mappedElementCount;
-  protected boolean isVertexAttribute;
-  protected long vboOffset;
   protected int vboName;
+  protected long vboOffset;
   protected boolean vboEnabled;
   protected int vboUsage;
   protected int vboTarget;