1 files changed, 138 insertions, 0 deletions
diff --git a/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java b/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
new file mode 100644
index 000000000..b7ea4f826
--- /dev/null
+++ b/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
@@ -0,0 +1,138 @@
+package jogamp.opengl;
+
+import javax.media.nativewindow.NativeSurface;
+import javax.media.opengl.GL;
+import javax.media.opengl.GL2GL3;
+import javax.media.opengl.GLCapabilitiesImmutable;
+import javax.media.opengl.GLContext;
+import javax.media.opengl.GLException;
+
+import com.jogamp.nativewindow.MutableGraphicsConfiguration;
+import com.jogamp.opengl.FBObject;
+import com.jogamp.opengl.FBObject.Attachment;
+import com.jogamp.opengl.FBObject.TextureAttachment;
+
+/**
+ * Offscreen GLDrawable implementation using framebuffer object (FBO)
+ * as it's offscreen rendering mechanism.
+ * 
+ * @see GLDrawableImpl#contextRealized(GLContext, boolean)
+ * @see GLDrawableImpl#contextMadeCurrent(GLContext, boolean)
+ * @see GLDrawableImpl#getDefaultDrawFramebuffer()
+ * @see GLDrawableImpl#getDefaultReadFramebuffer()
+ */
+public class GLFBODrawableImpl extends GLDrawableImpl {
+    final GLDrawableImpl parent;
+    final FBObject fbo;
+    int texUnit;
+    int samplesTexUnit = 0;
+    int width=0, height=0, samples=0;
+    
+    protected GLFBODrawableImpl(GLDrawableFactoryImpl factory, GLDrawableImpl parent, 
+                                NativeSurface surface, int initialWidth, int initialHeight, int textureUnit) {
+        super(factory, surface, false);
+        this.parent = parent;
+        this.texUnit = textureUnit;
+        final GLCapabilitiesImmutable caps = (GLCapabilitiesImmutable) surface.getGraphicsConfiguration().getChosenCapabilities();
+        this.width = initialWidth;
+        this.height = initialHeight;
+        this.samples = caps.getNumSamples();
+        this.fbo = new FBObject();
+    }
+    
+    @Override
+    protected void contextRealized(GLContext glc, boolean realized) {
+        final GLCapabilitiesImmutable caps = (GLCapabilitiesImmutable) surface.getGraphicsConfiguration().getChosenCapabilities();
+        final GL gl = glc.getGL();
+        if(realized) {                   
+            fbo.reset(gl, width, height, samples);
+            samples = fbo.getNumSamples(); // update, maybe capped
+            if(samples > 0) {
+                fbo.attachColorbuffer(gl, 0, caps.getAlphaBits()>0);
+            } else {
+                fbo.attachTexture2D(gl, 0, caps.getAlphaBits()>0);
+            }
+            if( caps.getStencilBits() > 0 ) {
+                fbo.attachRenderbuffer(gl, Attachment.Type.DEPTH_STENCIL, 24);
+            } else {
+                fbo.attachRenderbuffer(gl, Attachment.Type.DEPTH, 24);
+            }
+        } else if(null != fbo) {
+            fbo.destroy(gl);
+        }
+    }
+    
+    @Override
+    protected void contextMadeCurrent(GLContext glc, boolean current) {
+        final GL gl = glc.getGL();
+        if(current) {
+            fbo.bind(gl);
+        } else {
+            fbo.unbind(gl);
+            gl.glActiveTexture(GL.GL_TEXTURE0 + texUnit);
+            fbo.use(gl, samples > 0 ? fbo.getSamplingSink() : (TextureAttachment) fbo.getColorbuffer(0) );
+            if( samples > 0) {
+                gl.glBindFramebuffer(GL2GL3.GL_READ_FRAMEBUFFER, fbo.getReadFramebuffer());
+            }
+        }
+    }
+    
+    @Override
+    protected int getDefaultDrawFramebuffer() { return fbo.getWriteFramebuffer(); }
+    
+    @Override
+    protected int getDefaultReadFramebuffer() { return fbo.getReadFramebuffer(); }
+    
+    public FBObject getFBObject() { return fbo; }
+    
+    public void setSize(GL gl, int newWidth, int newHeight) throws GLException {
+        width = newWidth;
+        height = newHeight;        
+        fbo.reset(gl, width, height, samples);
+        samples = fbo.getNumSamples(); // update, maybe capped
+    }
+    
+    public void setSamples(GL gl, int newSamples) throws GLException {
+        samples = newSamples;
+        fbo.reset(gl, width, height, samples);
+        samples = fbo.getNumSamples(); // update, maybe capped
+    }
+    
+    
+    @Override
+    public GLContext createContext(GLContext shareWith) {
+        final GLContext ctx = parent.createContext(shareWith);
+        ctx.setGLDrawable(this, false);
+        return ctx;
+    }
+
+    @Override
+    public GLDynamicLookupHelper getGLDynamicLookupHelper() {
+        return parent.getGLDynamicLookupHelper();
+    }
+
+    @Override
+    protected void swapBuffersImpl() {
+    }
+
+    @Override
+    protected void setRealizedImpl() {
+        parent.setRealized(realized);
+        if(realized) {    
+            final MutableGraphicsConfiguration msConfig = (MutableGraphicsConfiguration) surface.getGraphicsConfiguration();
+            final GLCapabilitiesImmutable chosenCaps = (GLCapabilitiesImmutable) msConfig.getChosenCapabilities();
+            final GLCapabilitiesImmutable chosenFBOCaps = GLGraphicsConfigurationUtil.fixOffscreenGLCapabilities(chosenCaps, true /*FBO*/, false /*PBO*/);    
+            msConfig.setChosenCapabilities(chosenFBOCaps);
+        }
+    }
+
+    @Override
+    public int getWidth() {
+        return width;
+    }
+
+    @Override
+    public int getHeight() {
+        return height;
+    }    
+}