Cleanup GLContext special entries: getOffscreenContextPixelDataType(), getOffscreenContextReadBuffer(), .. ; Add GLFBODrawable API entries for multi buffering (no impl. yet); GLJPanel 1st simplification using offscreen drawable

- Cleanup GLContext special entries: getOffscreenContextPixelDataType(), getOffscreenContextReadBuffer(), .. ;
  - add: getDefaultReadBuffer() (-> exposed via GLBase as well)
  - add: isGLOrientationFlippedVertical()
  - add: getDefaultPixelDataType()
  - removed impl: getOffscreenContextPixelDataType()
  - removed impl: getOffscreenContextReadBuffer()
  - removed impl: offscreenImageNeedsVerticalFlip()

- Add GLFBODrawable API entries for multi buffering (no impl. yet);
  - TODO: Add implementation code in GLFBODrawableImpl

- GLJPanel 1st simplification using FBO
  - Use above new GL/GLContext entries
  - Fix: getNativeSurface() and getHandle()
  - TODO:
    - Remove distinction of 'pbuffer' and 'software',
    - Use GLDrawableFactory.createOffscreenDrawable(..)
    - Use GL for FBO swapping

11 files changed, 81 insertions, 98 deletions

diff --git a/src/jogl/classes/jogamp/opengl/GLContextImpl.java b/src/jogl/classes/jogamp/opengl/GLContextImpl.java
index 65b523394..24fc466b1 100644
--- a/src/jogl/classes/jogamp/opengl/GLContextImpl.java
+++ b/src/jogl/classes/jogamp/opengl/GLContextImpl.java
@@ -1513,15 +1513,46 @@ public abstract class GLContextImpl extends GLContext {
     throw new GLException("Not supported on non-pbuffer contexts");
   }
 
-  /** On some platforms the mismatch between OpenGL's coordinate
-      system (origin at bottom left) and the window system's
-      coordinate system (origin at top left) necessitates a vertical
-      flip of pixels read from offscreen contexts. */
-  public abstract boolean offscreenImageNeedsVerticalFlip();
+  @Override
+  public boolean isGLOrientationFlippedVertical() {
+      return true;
+  }
 
-  /** Only called for offscreen contexts; needed by glReadPixels */
-  public abstract int getOffscreenContextPixelDataType();
+  @Override
+  public int getDefaultPixelDataType() {
+      if(!pixelDataTypeEvaluated) {
+          synchronized(this) {
+              if(!pixelDataTypeEvaluated) {
+                  evalPixelDataType();
+                  pixelDataTypeEvaluated = true;
+              }
+          }
+      }
+      return pixelDataType;
+  }
 
+  private volatile boolean pixelDataTypeEvaluated = false; 
+  int /* pixelDataInternalFormat, */ pixelDataFormat, pixelDataType;
+  
+  private final void evalPixelDataType() {
+    /* if(isGL2GL3() && 3 == components) {
+        pixelDataInternalFormat=GL.GL_RGB;
+        pixelDataFormat=GL.GL_RGB;
+        pixelDataType = GL.GL_UNSIGNED_BYTE;            
+    } else */ if(isGLES2Compatible() || isExtensionAvailable(GLExtensions.OES_read_format)) {
+        final int[] glImplColorReadVals = new int[] { 0, 0 };
+        gl.glGetIntegerv(GL.GL_IMPLEMENTATION_COLOR_READ_FORMAT, glImplColorReadVals, 0);
+        gl.glGetIntegerv(GL.GL_IMPLEMENTATION_COLOR_READ_TYPE, glImplColorReadVals, 1);            
+        // pixelDataInternalFormat = (4 == components) ? GL.GL_RGBA : GL.GL_RGB;
+        pixelDataFormat = glImplColorReadVals[0];
+        pixelDataType = glImplColorReadVals[1];
+    } else {
+        // RGBA read is safe for all GL profiles 
+        // pixelDataInternalFormat = (4 == components) ? GL.GL_RGBA : GL.GL_RGB;
+        pixelDataFormat=GL.GL_RGBA;
+        pixelDataType = GL.GL_UNSIGNED_BYTE;
+    }            
+  }
 
   //----------------------------------------------------------------------
   // Helpers for buffer object optimizations
@@ -1599,8 +1630,10 @@ public abstract class GLContextImpl extends GLContext {
   @Override
   public final int getDefaultDrawFramebuffer() { return drawable.getDefaultDrawFramebuffer(); }  
   @Override
-  public final int getDefaultReadFramebuffer() { return drawable.getDefaultReadFramebuffer(); }
-  
+  public final int getDefaultReadFramebuffer() { return drawable.getDefaultReadFramebuffer(); }  
+  @Override
+  public final int getDefaultReadBuffer() { return drawable.getDefaultReadBuffer(gl); }
+    
   //---------------------------------------------------------------------------
   // GL_ARB_debug_output, GL_AMD_debug_output helpers
   //
diff --git a/src/jogl/classes/jogamp/opengl/GLDrawableImpl.java b/src/jogl/classes/jogamp/opengl/GLDrawableImpl.java
index df7f742aa..ccf0a8f0d 100644
--- a/src/jogl/classes/jogamp/opengl/GLDrawableImpl.java
+++ b/src/jogl/classes/jogamp/opengl/GLDrawableImpl.java
@@ -244,7 +244,16 @@ public abstract class GLDrawableImpl implements GLDrawable {
   /** Callback for special implementations, allowing GLContext to fetch a custom default render framebuffer. Defaults to zero.*/
   protected int getDefaultDrawFramebuffer() { return 0; }
   /** Callback for special implementations, allowing GLContext to fetch a custom default read framebuffer. Defaults to zero. */
-  protected int getDefaultReadFramebuffer() { return 0; }
+  protected int getDefaultReadFramebuffer() { return 0; }  
+  /** Callback for special implementations, allowing GLContext to fetch a custom default read buffer of current framebuffer. */
+  protected int getDefaultReadBuffer(GL gl) {
+      if(gl.isGLES() || getChosenGLCapabilities().getDoubleBuffered()) {
+          // Note-1: Neither ES1 nor ES2 supports selecting the read buffer via glReadBuffer
+          // Note-2: ES3 only supports GL_BACK, GL_NONE or GL_COLOR_ATTACHMENT0+i
+          return GL.GL_BACK;
+      }
+      return GL.GL_FRONT ; 
+  }
   
   @Override
   public final synchronized boolean isRealized() {
diff --git a/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java b/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
index 7a468a41e..b72f79868 100644
--- a/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
+++ b/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
@@ -302,6 +302,9 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
     protected final int getDefaultReadFramebuffer() { return initialized ? fbos[fboIFront].getReadFramebuffer() : 0; }
 
     @Override
+    protected final int getDefaultReadBuffer(GL gl) { return initialized ? fbos[fboIFront].getDefaultReadBuffer() : GL.GL_COLOR_ATTACHMENT0 ; }
+    
+    @Override
     protected final void setRealizedImpl() {
         final MutableGraphicsConfiguration msConfig = (MutableGraphicsConfiguration) surface.getGraphicsConfiguration();
         if(realized) {
@@ -435,6 +438,17 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
         }
     }
     
+    @Override
+    public final int setNumBuffers(int bufferCount) throws GLException {
+        // FIXME: Implement
+        return bufferCount;
+    }
+    
+    @Override
+    public final int getNumBuffers() {
+        return bufferCount;
+    }
+    
     /** // TODO: Add or remove TEXTURE (only) DoubleBufferMode support
     @Override
     public final DoubleBufferMode getDoubleBufferMode() {
diff --git a/src/jogl/classes/jogamp/opengl/GLOffscreenAutoDrawableImpl.java b/src/jogl/classes/jogamp/opengl/GLOffscreenAutoDrawableImpl.java
index 7701f209f..59a00170d 100644
--- a/src/jogl/classes/jogamp/opengl/GLOffscreenAutoDrawableImpl.java
+++ b/src/jogl/classes/jogamp/opengl/GLOffscreenAutoDrawableImpl.java
@@ -95,6 +95,16 @@ public class GLOffscreenAutoDrawableImpl extends GLAutoDrawableDelegate implemen
             windowRepaintOp();
         }
         
+        @Override
+        public final int setNumBuffers(int bufferCount) throws GLException {
+            return ((GLFBODrawableImpl)drawable).setNumBuffers(bufferCount);
+        }
+        
+        @Override
+        public final int getNumBuffers() {
+            return ((GLFBODrawableImpl)drawable).getNumBuffers();
+        }
+        
         /** // TODO: Add or remove TEXTURE (only) DoubleBufferMode support
         @Override
         public DoubleBufferMode getDoubleBufferMode() {
diff --git a/src/jogl/classes/jogamp/opengl/egl/EGLContext.java b/src/jogl/classes/jogamp/opengl/egl/EGLContext.java
index 84aeaa94a..deb3813b1 100644
--- a/src/jogl/classes/jogamp/opengl/egl/EGLContext.java
+++ b/src/jogl/classes/jogamp/opengl/egl/EGLContext.java
@@ -344,14 +344,4 @@ public abstract class EGLContext extends GLContextImpl {
     public ByteBuffer glAllocateMemoryNV(int arg0, float arg1, float arg2, float arg3) {
         throw new GLException("Should not call this");
     }
-
-    @Override
-    public boolean offscreenImageNeedsVerticalFlip() {
-        throw new GLException("Should not call this");
-    }
-
-    @Override
-    public int getOffscreenContextPixelDataType() {
-        throw new GLException("Should not call this");
-    }
 }
diff --git a/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLContext.java b/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLContext.java
index cde9841b8..63ed2ab7d 100644
--- a/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLContext.java
+++ b/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLContext.java
@@ -420,20 +420,6 @@ public abstract class MacOSXCGLContext extends GLContextImpl
     return super.isExtensionAvailable(glExtensionName);
   }
 
-  @Override
-  public int getOffscreenContextPixelDataType() {
-    throw new GLException("Should not call this");
-  }
-
-  public int getOffscreenContextReadBuffer() {
-    throw new GLException("Should not call this");
-  }
-
-  @Override
-  public boolean offscreenImageNeedsVerticalFlip() {
-    throw new GLException("Should not call this");
-  }
-
   // Support for "mode switching" as described in MacOSXCGLDrawable
   public void setOpenGLMode(GLBackendType mode) {
       if (mode == openGLMode) {
diff --git a/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXOffscreenCGLContext.java b/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXOffscreenCGLContext.java
index 7b13ce22e..f2e636796 100644
--- a/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXOffscreenCGLContext.java
+++ b/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXOffscreenCGLContext.java
@@ -49,18 +49,8 @@ public class MacOSXOffscreenCGLContext extends MacOSXPbufferCGLContext
   }
 
   @Override
-  public int getOffscreenContextPixelDataType() {
-    GL gl = getGL();
+  public int getDefaultPixelDataType() {
+    final GL gl = getGL();
     return gl.isGL2GL3()?GL2GL3.GL_UNSIGNED_INT_8_8_8_8_REV:GL.GL_UNSIGNED_SHORT_5_5_5_1;
   }
-
-  @Override
-  public int getOffscreenContextReadBuffer() {
-    return GL.GL_FRONT;
-  }
-
-  @Override
-  public boolean offscreenImageNeedsVerticalFlip() {
-    return true;
-  }
 }
diff --git a/src/jogl/classes/jogamp/opengl/windows/wgl/WindowsBitmapWGLContext.java b/src/jogl/classes/jogamp/opengl/windows/wgl/WindowsBitmapWGLContext.java
index 51341a098..c8aac7f7b 100644
--- a/src/jogl/classes/jogamp/opengl/windows/wgl/WindowsBitmapWGLContext.java
+++ b/src/jogl/classes/jogamp/opengl/windows/wgl/WindowsBitmapWGLContext.java
@@ -49,18 +49,12 @@ public class WindowsBitmapWGLContext extends WindowsWGLContext {
   }
 
   @Override
-  public int getOffscreenContextPixelDataType() {
+  public int getDefaultPixelDataType() {
       return GL.GL_UNSIGNED_BYTE;
   }
 
   @Override
-  public int getOffscreenContextReadBuffer() {
-    // On Windows these contexts are always single-buffered
-    return GL.GL_FRONT;
-  }
-
-  @Override
-  public boolean offscreenImageNeedsVerticalFlip() {
+  public boolean isGLOrientationFlippedVertical() {
     // We can take care of this in the DIB creation (see below)
     return false;
   }
diff --git a/src/jogl/classes/jogamp/opengl/windows/wgl/WindowsWGLContext.java b/src/jogl/classes/jogamp/opengl/windows/wgl/WindowsWGLContext.java
index 57f16522c..92d75e3fd 100644
--- a/src/jogl/classes/jogamp/opengl/windows/wgl/WindowsWGLContext.java
+++ b/src/jogl/classes/jogamp/opengl/windows/wgl/WindowsWGLContext.java
@@ -538,20 +538,6 @@ public class WindowsWGLContext extends GLContextImpl {
   }
 
   @Override
-  public int getOffscreenContextPixelDataType() {
-    throw new GLException("Should not call this");
-  }
-
-  public int getOffscreenContextReadBuffer() {
-    throw new GLException("Should not call this");
-  }
-
-  @Override
-  public boolean offscreenImageNeedsVerticalFlip() {
-    throw new GLException("Should not call this");
-  }
-
-  @Override
   public void bindPbufferToTexture() {
     throw new GLException("Should not call this");
   }
diff --git a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXContext.java b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXContext.java
index 76e0bc15c..bf1045132 100644
--- a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXContext.java
+++ b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXContext.java
@@ -619,20 +619,6 @@ public abstract class X11GLXContext extends GLContextImpl {
   }
 
   @Override
-  public int getOffscreenContextPixelDataType() {
-    throw new GLException("Should not call this");
-  }
-
-  public int getOffscreenContextReadBuffer() {
-    throw new GLException("Should not call this");
-  }
-
-  @Override
-  public boolean offscreenImageNeedsVerticalFlip() {
-    throw new GLException("Should not call this");
-  }
-
-  @Override
   public void bindPbufferToTexture() {
     throw new GLException("Should not call this");
   }
diff --git a/src/jogl/classes/jogamp/opengl/x11/glx/X11PixmapGLXContext.java b/src/jogl/classes/jogamp/opengl/x11/glx/X11PixmapGLXContext.java
index 96d0f18dc..1cfb7e427 100644
--- a/src/jogl/classes/jogamp/opengl/x11/glx/X11PixmapGLXContext.java
+++ b/src/jogl/classes/jogamp/opengl/x11/glx/X11PixmapGLXContext.java
@@ -50,24 +50,9 @@ public class X11PixmapGLXContext extends X11GLXContext {
   }
 
   @Override
-  public int getOffscreenContextPixelDataType() {
+  public int getDefaultPixelDataType() {
     GL gl = getGL();
     return gl.isGL2GL3()?GL2GL3.GL_UNSIGNED_INT_8_8_8_8_REV:GL.GL_UNSIGNED_SHORT_5_5_5_1;
   }
 
-  @Override
-  public int getOffscreenContextReadBuffer() {
-    GLCapabilitiesImmutable caps = (GLCapabilitiesImmutable)drawable.getNativeSurface().getGraphicsConfiguration().getChosenCapabilities();
-    if (caps.getDoubleBuffered()) {
-      return GL.GL_BACK;
-    }
-    return GL.GL_FRONT;
-  }
-
-  @Override
-  public boolean offscreenImageNeedsVerticalFlip() {
-    // There doesn't seem to be a way to do this in the construction
-    // of the Pixmap or GLXPixmap
-    return true;
-  }
 }