Bug 665: Allow re-association of GLContext/GLEventListener to a GLDrawable (Part 4)

Note:

  - GLEventListenerState preservs the GLAutoDrawable state,
    i.e. GLContext, all GLEventListener and the GLAnimatorControl association.

  - GLEventListenerState may be utilized to move the state from a dying GLAutoDrawable,
    to be moved to a new created GLAutoDrawable at a later time.

  - GLEventListenerState will be made public soon.

+++

Exessive unit tests cover the new feature, tested manually on GNU/Linux/X11 and OSX(Java6/Java7).

+++

- GLAutoDrawable
  - Change 'setContext(..)' to allow the destruction of the unbound old context:
      'setContext(GLContext newCtx)' -> 'setContext(GLContext newCtx, boolean destroyPrevCtx)'

  - Implementations: Properly implement 'setRealized(..)' incl. obeying threading constraints if exists.
    Method is being utilized at least for GLEventListenerState.moveTo(..)
    to unrealize and realize the drawable resources.

+++

Fix propagation of GLContext/GLDrawable association change (Bottom -> Top):

  GLDrawableImpl.associateContext
      GLContextImpl.associateDrawable
          GLContextImpl.makeCurrent
          GLContextImpl.destroy
          GLContext.setGLDrawable
              ...
              GLDrawableHelper.switchContext
                  GLAutoDrawble.setContext

associateDrawable(..)/associateContext(..) unifies and hence:
    - GLContextImpl.contextRealized() (removed)
    - GLDrawableImpl.contextRealized() (removed)
    - GLDrawableImpl.associateContext(..) (merged)
    - MacOSXCGLContext.drawableChangedNotify(..) (removed)

+++

- EGLUpstreamSurfaceHook.evalUpstreamSurface() validates the surface's device for reusage,
  which is valid in case of GLEventListenerState.moveTo(..)

- MacOSXCGLContext.NSOpenGLImpl: pixelFormat replaces NSOpenGLLayerPfmt and has simplified lifecycle [create..destroy],
  while native NSOpenGLLayer code only holds the reference until released.

17 files changed, 308 insertions, 275 deletions

diff --git a/src/jogl/classes/com/jogamp/opengl/GLAutoDrawableDelegate.java b/src/jogl/classes/com/jogamp/opengl/GLAutoDrawableDelegate.java
index 0f0f03ac4..bec05a0bd 100644
--- a/src/jogl/classes/com/jogamp/opengl/GLAutoDrawableDelegate.java
+++ b/src/jogl/classes/com/jogamp/opengl/GLAutoDrawableDelegate.java
@@ -170,11 +170,6 @@ public class GLAutoDrawableDelegate extends GLAutoDrawableBase implements GLAuto
     }
     
     @Override
-    public final void setRealized(boolean realized) {
-        drawable.setRealized(realized);
-    }
-
-    @Override
     public final void swapBuffers() throws GLException {
          defaultSwapBuffers();
     }
diff --git a/src/jogl/classes/com/jogamp/opengl/swt/GLCanvas.java b/src/jogl/classes/com/jogamp/opengl/swt/GLCanvas.java
index 80e1aa80d..169266152 100644
--- a/src/jogl/classes/com/jogamp/opengl/swt/GLCanvas.java
+++ b/src/jogl/classes/com/jogamp/opengl/swt/GLCanvas.java
@@ -705,16 +705,13 @@ public class GLCanvas extends Canvas implements GLAutoDrawable {
    }
 
    @Override
-   public GLContext setContext(GLContext newCtx) {
+   public GLContext setContext(GLContext newCtx, boolean destroyPrevCtx) {
       final RecursiveLock _lock = lock;
       _lock.lock();
       try {            
           final GLContext oldCtx = context;
-          final boolean newCtxCurrent = GLDrawableHelper.switchContext(drawable, oldCtx, newCtx, additionalCtxCreationFlags);
+          GLDrawableHelper.switchContext(drawable, oldCtx, destroyPrevCtx, newCtx, additionalCtxCreationFlags);
           context=(GLContextImpl)newCtx;
-          if(newCtxCurrent) {
-              context.makeCurrent();
-          }
           return oldCtx;
       } finally {
           _lock.unlock();
diff --git a/src/jogl/classes/com/jogamp/opengl/util/GLDrawableUtil.java b/src/jogl/classes/com/jogamp/opengl/util/GLDrawableUtil.java
index c03e4bfa4..83414ddb0 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/GLDrawableUtil.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/GLDrawableUtil.java
@@ -151,7 +151,7 @@ public class GLDrawableUtil {
     for(int i = dest.getGLEventListenerCount() - 1; 0 <= i; i--) {
         dest.disposeGLEventListener(dest.getGLEventListener(i), false);
     }
-    dest.setContext( src.setContext( dest.getContext() ) );
+    dest.setContext( src.setContext( dest.getContext(), false ), false );
     
     src.invoke(true, GLEventListenerState.setViewport);
     dest.invoke(true, GLEventListenerState.setViewport);
diff --git a/src/jogl/classes/javax/media/opengl/GLAutoDrawable.java b/src/jogl/classes/javax/media/opengl/GLAutoDrawable.java
index 6abe4308b..bdbbd96a5 100644
--- a/src/jogl/classes/javax/media/opengl/GLAutoDrawable.java
+++ b/src/jogl/classes/javax/media/opengl/GLAutoDrawable.java
@@ -132,7 +132,8 @@ public interface GLAutoDrawable extends GLDrawable {
   /**
    * Associate the new context, <code>newtCtx</code>, to this auto-drawable.
    * <p>
-   * The current context will be dis-associated from this auto-drawable 
+   * The current context will be destroyed if <code>destroyPrevCtx</code> is <code>true</code>,
+   * otherwise it will be dis-associated from this auto-drawable 
    * via {@link GLContext#setGLDrawable(GLDrawable, boolean) setGLDrawable(null, true);} first.
    * </p>
    * <p>
@@ -145,26 +146,16 @@ public interface GLAutoDrawable extends GLDrawable {
    * However the user shall take extra care that no other thread
    * attempts to make this context current.
    * </p>
-   * <p>
-   * In case you do not intend to use the old context anymore, i.e. 
-   * not assigning it to another drawable, it shall be
-   * destroyed, i.e.:
-   * <pre>
-            GLContext oldCtx = glad.setContext(newCtx);
-            if(null != oldCtx) {
-                oldCtx.destroy();
-            }
-   * </pre> 
-   * </p>
    * 
    * @param newCtx the new context, maybe <code>null</code> for dis-association.
+   * @param destroyPrevCtx if <code>true</code>, destroy the previous context if exists  
    * @return the previous GLContext, maybe <code>null</code>
    *  
    * @see GLContext#setGLDrawable(GLDrawable, boolean)
    * @see GLContext#setGLReadDrawable(GLDrawable)
-   * @see jogamp.opengl.GLDrawableHelper#switchContext(GLDrawable, GLContext, GLContext, int)
+   * @see jogamp.opengl.GLDrawableHelper#switchContext(GLDrawable, GLContext, boolean, GLContext, int)
    */
-  public GLContext setContext(GLContext newCtx);
+  public GLContext setContext(GLContext newCtx, boolean destroyPrevCtx);
   
   /**
    * Adds the given {@link GLEventListener listener} to the end of this drawable queue.
@@ -500,7 +491,7 @@ public interface GLAutoDrawable extends GLDrawable {
    * <p>
    * This GLAutoDrawable implementation holds it's own GLContext reference,
    * thus created a GLContext using this methods won't replace it implicitly.
-   * To replace or set this GLAutoDrawable's GLContext you need to call {@link #setContext(GLContext)}. 
+   * To replace or set this GLAutoDrawable's GLContext you need to call {@link #setContext(GLContext, boolean)}. 
    * </p>
    * <p>
    * The GLAutoDrawable implementation shall also set the 
diff --git a/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java b/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java
index ebc25e2ad..63c18db5d 100644
--- a/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java
+++ b/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java
@@ -429,8 +429,29 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
     }
   }
     
+  private final void setRealizedImpl(boolean realized) {
+      final RecursiveLock _lock = lock;
+      _lock.lock();
+      try {            
+          final GLDrawable _drawable = drawable;
+          if( null == _drawable || realized && ( 0 >= _drawable.getWidth() || 0 >= _drawable.getHeight() ) ) {
+              return; 
+          }
+         _drawable.setRealized(realized);
+          if( realized && _drawable.isRealized() ) {
+              sendReshape=true; // ensure a reshape is being send ..
+          }
+      } finally {
+          _lock.unlock();
+      }
+  }  
+  private final Runnable realizeOnEDTAction = new Runnable() { public void run() { setRealizedImpl(true); } };
+  private final Runnable unrealizeOnEDTAction = new Runnable() { public void run() { setRealizedImpl(false); } };
+  
   @Override
-  public void setRealized(boolean realized) {
+  public final void setRealized(boolean realized) {
+      // Make sure drawable realization happens on AWT-EDT and only there. Consider the AWTTree lock!
+      AWTEDTExecutor.singleton.invoke(getTreeLock(), false /* allowOnNonEDT */, true /* wait */, realized ? realizeOnEDTAction : unrealizeOnEDTAction);
   }
 
   @Override
@@ -595,46 +616,28 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
   }  
 
   private boolean validateGLDrawable() {
-    if( Beans.isDesignTime() || !isDisplayable() ) {
-        return false; // early out!
-    }
-    final GLDrawable _drawable = drawable;
-    if ( null != _drawable ) {
-        if( _drawable.isRealized() ) {
-            return true;
-        }
-        if( 0 >= _drawable.getWidth() || 0 >= _drawable.getHeight() ) {
-            return false; // early out!
-        }
-        // Make sure drawable realization happens on AWT-EDT and only there. Consider the AWTTree lock!
-        final boolean res0 = AWTEDTExecutor.singleton.invoke(getTreeLock(), false /* allowOnNonEDT */, true /* wait */, setRealizedOnEDTAction);
-        final boolean res1 = res0 && _drawable.isRealized();
-        if(DEBUG) {
-            System.err.println(getThreadName()+": Realized Drawable: invoked "+res0+", probedIsRealized "+res1+", "+_drawable.toString());
-            Thread.dumpStack();
-        }
-        return res1;
-    }
-    return false;
-  }
-  private Runnable setRealizedOnEDTAction = new Runnable() { 
-      public void run() { 
-          final RecursiveLock _lock = lock;
-          _lock.lock();
-          try {            
-              final GLDrawable _drawable = drawable;
-              if( null == _drawable || 0 >= _drawable.getWidth() || 0 >= _drawable.getHeight() ) {
-                  return; 
-              }
-              _drawable.setRealized(true);
-              if( _drawable.isRealized() ) {
-                  sendReshape=true; // ensure a reshape is being send ..
-              }
-          } finally {
-              _lock.unlock();
+      if( Beans.isDesignTime() || !isDisplayable() ) {
+          return false; // early out!
+      }
+      final GLDrawable _drawable = drawable;
+      if ( null != _drawable ) {
+          if( _drawable.isRealized() ) {
+              return true;
           }
-      } };
-
+          if( 0 >= _drawable.getWidth() || 0 >= _drawable.getHeight() ) {
+              return false; // early out!
+          }
+          setRealized(true);
+          final boolean res = _drawable.isRealized();
+          if(DEBUG) {
+              System.err.println(getThreadName()+": Realized Drawable: isRealized "+res+", "+_drawable.toString());
+              Thread.dumpStack();
+          }
+          return res;
+      }
+      return false;
+  }
+  
   /** <p>Overridden to track when this component is removed from a
       container. Subclasses which override this method must call
       super.removeNotify() in their removeNotify() method in order to
@@ -791,16 +794,13 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
   }
   
   @Override
-  public GLContext setContext(GLContext newCtx) {
+  public GLContext setContext(GLContext newCtx, boolean destroyPrevCtx) {
       final RecursiveLock _lock = lock;
       _lock.lock();
       try {
           final GLContext oldCtx = context;
-          final boolean newCtxCurrent = GLDrawableHelper.switchContext(drawable, oldCtx, newCtx, additionalCtxCreationFlags);
+          GLDrawableHelper.switchContext(drawable, oldCtx, destroyPrevCtx, newCtx, additionalCtxCreationFlags);
           context=(GLContextImpl)newCtx;
-          if(newCtxCurrent) {
-              context.makeCurrent();
-          }
           return oldCtx;
       } finally {
           _lock.unlock();
diff --git a/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java b/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java
index 8d9493cbf..d62967d7f 100644
--- a/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java
+++ b/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java
@@ -519,16 +519,13 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
   }
 
   @Override
-  public GLContext setContext(GLContext newCtx) {
+  public GLContext setContext(GLContext newCtx, boolean destroyPrevCtx) {
       if (backend == null) {
           return null;
       }
       final GLContext oldCtx = backend.getContext();
-      final boolean newCtxCurrent = GLDrawableHelper.switchContext(backend.getDrawable(), oldCtx, newCtx, additionalCtxCreationFlags);
+      GLDrawableHelper.switchContext(backend.getDrawable(), oldCtx, destroyPrevCtx, newCtx, additionalCtxCreationFlags);
       backend.setContext(newCtx);
-      if(newCtxCurrent) {
-          newCtx.makeCurrent();
-      }
       return oldCtx;
   }
 
diff --git a/src/jogl/classes/jogamp/opengl/GLAutoDrawableBase.java b/src/jogl/classes/jogamp/opengl/GLAutoDrawableBase.java
index c20197e72..ad67f8281 100644
--- a/src/jogl/classes/jogamp/opengl/GLAutoDrawableBase.java
+++ b/src/jogl/classes/jogamp/opengl/GLAutoDrawableBase.java
@@ -326,16 +326,13 @@ public abstract class GLAutoDrawableBase implements GLAutoDrawable, FPSCounter {
     }
 
     @Override
-    public final GLContext setContext(GLContext newCtx) {
+    public final GLContext setContext(GLContext newCtx, boolean destroyPrevCtx) {
         final RecursiveLock lock = getLock();
         lock.lock();
         try {
             final GLContext oldCtx = context;
-            final boolean newCtxCurrent = GLDrawableHelper.switchContext(drawable, oldCtx, newCtx, additionalCtxCreationFlags);
+            GLDrawableHelper.switchContext(drawable, oldCtx, destroyPrevCtx, newCtx, additionalCtxCreationFlags);
             context=(GLContextImpl)newCtx;
-            if(newCtxCurrent) { // implies null != newCtx
-                context.makeCurrent();
-            }
             return oldCtx;
         } finally {
             lock.unlock();
@@ -531,6 +528,24 @@ public abstract class GLAutoDrawableBase implements GLAutoDrawable, FPSCounter {
     }
 
     @Override
+    public final void setRealized(boolean realized) {
+        final RecursiveLock _lock = getLock();
+        _lock.lock();
+        try {            
+            final GLDrawable _drawable = drawable;
+            if( null == _drawable || realized && ( 0 >= _drawable.getWidth() || 0 >= _drawable.getHeight() ) ) {
+                return; 
+            }
+            _drawable.setRealized(realized);
+            if( realized && _drawable.isRealized() ) {
+                sendReshape=true; // ensure a reshape is being send ..
+            }
+        } finally {
+            _lock.unlock();
+        }
+    }
+    
+    @Override
     public final boolean isRealized() {
         final GLDrawable _drawable = drawable;
         return null != _drawable ? _drawable.isRealized() : false;
diff --git a/src/jogl/classes/jogamp/opengl/GLContextImpl.java b/src/jogl/classes/jogamp/opengl/GLContextImpl.java
index 42364dbfd..4121e8f77 100644
--- a/src/jogl/classes/jogamp/opengl/GLContextImpl.java
+++ b/src/jogl/classes/jogamp/opengl/GLContextImpl.java
@@ -133,9 +133,6 @@ public abstract class GLContextImpl extends GLContext {
     GLContextShareSet.synchronizeBufferObjectSharing(shareWith, this);
 
     this.drawable = drawable;
-    if(null != drawable) {
-        drawable.associateContext(this, true);
-    }
     this.drawableRead = drawable;
 
     this.glDebugHandler = new GLDebugMessageHandler(this);
@@ -207,25 +204,36 @@ public abstract class GLContextImpl extends GLContext {
         return drawable; // no change.
     }
     final Thread currentThread = Thread.currentThread();
+    if( lock.isLockedByOtherThread() ) {
+        throw new GLException("GLContext current by other thread "+lock.getOwner().getName()+", operation not allowed on this thread "+currentThread.getName());
+    }    
     final boolean lockHeld = lock.isOwner(currentThread);
+    if( lockHeld && lock.getHoldCount() > 1 ) {
+        // would need to makeCurrent * holdCount
+        throw new GLException("GLContext is recursively locked - unsupported for setGLDrawable(..)");
+    }
+    final GLDrawableImpl old = drawable;
+    if( isCreated() && null != old && old.isRealized() ) {
+        if(!lockHeld) {
+            makeCurrent();
+        }
+        associateDrawable(false);
+        if(!lockHeld) {
+            release();
+        }
+    }
     if(lockHeld) {
         release();
-    } else if(lock.isLockedByOtherThread()) { // still could glitch ..
-        throw new GLException("GLContext current by other thread "+lock.getOwner().getName()+", operation not allowed on this thread "+currentThread.getName());
-    }    
+    }
     if( !setWriteOnly || drawableRead == drawable ) { // if !setWriteOnly || !explicitReadDrawable
         drawableRead = (GLDrawableImpl) readWrite;
     }
-    final GLDrawableImpl old = drawable;
-    if( null != old ) {
-        old.associateContext(this, false);
-    }
     drawableRetargeted |= null != drawable && readWrite != drawable;
     drawable = (GLDrawableImpl) readWrite ;
-    if( null != drawable ) {
-        drawable.associateContext(this, true);
-        if( lockHeld ) {
-            makeCurrent();
+    if( isCreated() && null != drawable && drawable.isRealized() ) {
+        makeCurrent(true); // implicit: associateDrawable(true)
+        if( !lockHeld ) {
+            release();
         }
     }
     return old;
@@ -363,8 +371,7 @@ public abstract class GLContextImpl extends GLContext {
                       makeCurrent();
                   }
                   try {
-                      contextRealized(false);
-                      drawable.associateContext(this, false);
+                      associateDrawable(false);
                   } catch (Throwable t) {
                       drawableContextRealizedException = t;
                   }
@@ -467,7 +474,11 @@ public abstract class GLContextImpl extends GLContext {
    * @see #destroyContextARBImpl
    */
   @Override
-  public int makeCurrent() throws GLException {
+  public final int makeCurrent() throws GLException {
+      return makeCurrent(false);
+  }
+  
+  protected final int makeCurrent(boolean forceDrawableAssociation) throws GLException {
     if( TRACE_SWITCH ) {
         System.err.println(getThreadName() +": GLContext.ContextSwitch[makeCurrent.0]: obj " + toHexString(hashCode()) + ", ctx "+toHexString(contextHandle)+", surf "+toHexString(drawable.getHandle())+" - "+lock);
     }      
@@ -561,7 +572,11 @@ public abstract class GLContextImpl extends GLContext {
             gl = gl.getContext().setGL( GLPipelineFactory.create("javax.media.opengl.Trace", null, gl, new Object[] { System.err } ) );
         }
         
-        contextRealized(true);        
+        forceDrawableAssociation = true;
+      }
+      
+      if( forceDrawableAssociation ) {
+          associateDrawable(true);
       }
       
       contextMadeCurrent(true);
@@ -662,14 +677,14 @@ public abstract class GLContextImpl extends GLContext {
   protected abstract void makeCurrentImpl() throws GLException;
 
   /**
-   * @see GLDrawableImpl#contextRealized(GLContext, boolean) 
+   * Calls {@link GLDrawableImpl#associateContext(GLContext, boolean)} 
    */ 
-  protected void contextRealized(boolean realized) {
-      drawable.contextRealized(this, realized);
+  protected void associateDrawable(boolean bound) { 
+      drawable.associateContext(this, bound);      
   }
   
   /**
-   * @see GLDrawableImpl#contextMadeCurrent(GLContext, boolean) 
+   * Calls {@link GLDrawableImpl#contextMadeCurrent(GLContext, boolean)} 
    */ 
   protected void contextMadeCurrent(boolean current) {
       drawable.contextMadeCurrent(this, current);      
diff --git a/src/jogl/classes/jogamp/opengl/GLDrawableHelper.java b/src/jogl/classes/jogamp/opengl/GLDrawableHelper.java
index 3eedf918e..1caa942ba 100644
--- a/src/jogl/classes/jogamp/opengl/GLDrawableHelper.java
+++ b/src/jogl/classes/jogamp/opengl/GLDrawableHelper.java
@@ -59,7 +59,7 @@ import javax.media.opengl.GLFBODrawable;
 import javax.media.opengl.GLRunnable;
 
 /** Encapsulates the implementation of most of the GLAutoDrawable's
-    methods to be able to share it between GLCanvas and GLJPanel. */
+    methods to be able to share it between GLAutoDrawable implementations like GLAutoDrawableBase, GLCanvas and GLJPanel. */
 public class GLDrawableHelper {
   /** true if property <code>jogl.debug.GLDrawable.PerfStats</code> is defined. */
   private static final boolean PERF_STATS = Debug.isPropertyDefined("jogl.debug.GLDrawable.PerfStats", true);
@@ -113,6 +113,9 @@ public class GLDrawableHelper {
     return sb.toString();
   }
 
+  /** Limit release calls of {@link #forceNativeRelease(GLContext)} to {@value}. */
+  private static final int MAX_RELEASE_ITER = 512;
+  
   /**
    * Since GLContext's {@link GLContext#makeCurrent()} and {@link GLContext#release()}
    * is recursive, a call to {@link GLContext#release()} may not natively release the context.
@@ -122,18 +125,25 @@ public class GLDrawableHelper {
    * @param ctx
    */
   public static final void forceNativeRelease(GLContext ctx) {
+      int releaseCount = 0;
       do {
           ctx.release();
+          releaseCount++;
           if (DEBUG) {
-              System.err.println("GLDrawableHelper.forceNativeRelease() -- currentThread "+Thread.currentThread()+" -> "+GLContext.getCurrent());
+              System.err.println("GLDrawableHelper.forceNativeRelease() #"+releaseCount+" -- currentThread "+Thread.currentThread()+" -> "+GLContext.getCurrent());
           }
-      } while( ctx == GLContext.getCurrent() );
+      } while( MAX_RELEASE_ITER > releaseCount && ctx.isCurrent() );
+      
+      if( ctx.isCurrent() ) {
+          throw new GLException("Context still current after "+MAX_RELEASE_ITER+" releases: "+ctx);
+      }
   }
         
   /**
    * Switch {@link GLContext} / {@link GLDrawable} association.
    * <p>
-   * Dis-associate <code>oldCtx</code> from <code>drawable</code> 
+   * The <code>oldCtx</code> will be destroyed if <code>destroyPrevCtx</code> is <code>true</code>,
+   * otherwise dis-associate <code>oldCtx</code> from <code>drawable</code> 
    * via {@link GLContext#setGLDrawable(GLDrawable, boolean) oldCtx.setGLDrawable(null, true);}.
    * </p>
    * <p>
@@ -149,31 +159,25 @@ public class GLDrawableHelper {
    * 
    * @param drawable the drawable which context is changed
    * @param oldCtx the old context, maybe <code>null</code>.
+   * @param destroyOldCtx if <code>true</code>, destroy the <code>oldCtx</code>
    * @param newCtx the new context, maybe <code>null</code> for dis-association.
    * @param newCtxCreationFlags additional creation flags if newCtx is not null and not been created yet, see {@link GLContext#setContextCreationFlags(int)}
-   * @return true if the new context was current, otherwise false
    *  
-   * @see GLAutoDrawable#setContext(GLContext)
+   * @see GLAutoDrawable#setContext(GLContext, boolean)
    */
-  public static final boolean switchContext(GLDrawable drawable, GLContext oldCtx, GLContext newCtx, int newCtxCreationFlags) {
+  public static final void switchContext(GLDrawable drawable, GLContext oldCtx, boolean destroyOldCtx, GLContext newCtx, int newCtxCreationFlags) {
       if( null != oldCtx ) {
-          if( oldCtx.isCurrent() ) {
-              oldCtx.release();
+          if( destroyOldCtx ) {
+              oldCtx.destroy();
+          } else {
+              oldCtx.setGLDrawable(null, true); // dis-associate old pair
           }
-          oldCtx.setGLDrawable(null, true); // dis-associate old pair
       }
-      final boolean newCtxCurrent;
+      
       if(null!=newCtx) {
-          newCtxCurrent = newCtx.isCurrent();
-          if(newCtxCurrent) {
-              newCtx.release();
-          }
           newCtx.setContextCreationFlags(newCtxCreationFlags);
-          newCtx.setGLDrawable(drawable, true); // re-associate new pair
-      } else {          
-          newCtxCurrent = false;
+          newCtx.setGLDrawable(drawable, true); // re-associate new pair          
       }
-      return newCtxCurrent;
   }
   
   /**
@@ -208,7 +212,6 @@ public class GLDrawableHelper {
               context.makeCurrent();
           }
           context.getGL().glFinish();
-          context.release();
           context.setGLDrawable(null, true); // dis-associate
       }
       
@@ -837,7 +840,7 @@ public class GLDrawableHelper {
         if( null != exclusiveContextThread ) {
             throw new GLException("Release current exclusive Context Thread "+exclusiveContextThread+" first");
         }
-        if( null != context && GLContext.getCurrent() == context ) {
+        if( null != context && context.isCurrent() ) {
             try {
                 forceNativeRelease(context);
             } catch (Throwable ex) {
diff --git a/src/jogl/classes/jogamp/opengl/GLDrawableImpl.java b/src/jogl/classes/jogamp/opengl/GLDrawableImpl.java
index c0c28a5f2..d0c1461a9 100644
--- a/src/jogl/classes/jogamp/opengl/GLDrawableImpl.java
+++ b/src/jogl/classes/jogamp/opengl/GLDrawableImpl.java
@@ -164,13 +164,14 @@ public abstract class GLDrawableImpl implements GLDrawable {
   @Override
   public final void setRealized(boolean realizedArg) {
     if ( realized != realizedArg ) { // volatile: OK (locked below)
+        final boolean isProxySurface = surface instanceof ProxySurface;
         if(DEBUG) {
-            System.err.println(getThreadName() + ": setRealized: "+getClass().getSimpleName()+" "+realized+" -> "+realizedArg);
+            System.err.println(getThreadName() + ": setRealized: drawable "+getClass().getSimpleName()+", surface "+surface.getClass().getSimpleName()+", isProxySurface "+isProxySurface+": "+realized+" -> "+realizedArg);
             Thread.dumpStack();
         }
         AbstractGraphicsDevice aDevice = surface.getGraphicsConfiguration().getScreen().getDevice();
         if(realizedArg) {
-            if(surface instanceof ProxySurface) {
+            if(isProxySurface) {
                 ((ProxySurface)surface).createNotify();
             }
             if(NativeSurface.LOCK_SURFACE_NOT_READY >= lockSurface()) {
@@ -195,7 +196,7 @@ public abstract class GLDrawableImpl implements GLDrawable {
                 unlockSurface();
             } else {
                 aDevice.unlock();
-                if(surface instanceof ProxySurface) {
+                if(isProxySurface) {
                     ((ProxySurface)surface).destroyNotify();
                 }
             }
@@ -210,18 +211,26 @@ public abstract class GLDrawableImpl implements GLDrawable {
    */
   protected abstract void setRealizedImpl();
 
-  /** 
-   * Callback for special implementations, allowing GLContext to trigger GL related lifecycle: <code>construct</code>, <code>destroy</code>.
+  /**
+   * Callback for special implementations, allowing
+   * <ul>
+   *   <li>to associate bound context to this drawable (bound == true) 
+   *       or to remove such association (bound == false).</li>
+   *   <li>to trigger GLContext/GLDrawable related lifecycle: <code>construct</code>, <code>destroy</code>.</li>
+   * </ul>
    * <p>
-   * If <code>realized</code> is <code>true</code>, the context has just been created and made current.
+   * If <code>bound</code> is <code>true</code>, the context is current and being newly associated w/ this drawable.
    * </p>
    * <p>
-   * If <code>realized</code> is <code>false</code>, the context is still current and will be released and destroyed after this method returns.
+   * If <code>bound</code> is <code>false</code>, the context is still current and will be unbound (released and destroyed, or simply disassociated).
    * </p>
    * <p>
-   * @see #contextMadeCurrent(GLContext, boolean)
+   * Being called by {@link GLContextImpl#associateDrawable(boolean)}.
+   * </p>
+   * @param ctx the just bounded or unbounded context
+   * @param bound if <code>true</code> create an association, otherwise remove it
    */
-  protected void contextRealized(GLContext glc, boolean realized) {}
+  protected void associateContext(GLContext ctx, boolean bound) { }
   
   /** 
    * Callback for special implementations, allowing GLContext to trigger GL related lifecycle: <code>makeCurrent</code>, <code>release</code>.
@@ -232,21 +241,12 @@ public abstract class GLDrawableImpl implements GLDrawable {
    * If <code>current</code> is <code>false</code>, the context is still current and will be release after this method returns.
    * </p>
    * <p>
-   * Note: Will also be called after {@link #contextRealized(GLContext, boolean) contextRealized(ctx, true)}
-   * but not at context destruction, i.e. {@link #contextRealized(GLContext, boolean) contextRealized(ctx, false)}.
+   * Being called by {@link GLContextImpl#contextMadeCurrent(boolean)}.
    * </p>
-   * @see #contextRealized(GLContext, boolean)
+   * @see #associateContext(GLContext, boolean)
    */ 
   protected void contextMadeCurrent(GLContext glc, boolean current) { }
 
-  /**
-   * Callback for special implementations, allowing to associate bound context to this drawable (bound == true) 
-   * or to remove such association (bound == false).
-   * @param ctx the just bounded or unbounded context
-   * @param bound if <code>true</code> create an association, otherwise remove it
-   */
-  protected void associateContext(GLContext ctx, boolean bound) { }
-  
   /** 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. */
diff --git a/src/jogl/classes/jogamp/opengl/GLEventListenerState.java b/src/jogl/classes/jogamp/opengl/GLEventListenerState.java
index 7a2569850..2385460fe 100644
--- a/src/jogl/classes/jogamp/opengl/GLEventListenerState.java
+++ b/src/jogl/classes/jogamp/opengl/GLEventListenerState.java
@@ -45,7 +45,6 @@ import javax.media.opengl.GLEventListener;
 import javax.media.opengl.GLException;
 import javax.media.opengl.GLRunnable;
 
-import com.jogamp.common.util.locks.RecursiveLock;
 import com.jogamp.nativewindow.MutableGraphicsConfiguration;
 
 /**
@@ -71,11 +70,12 @@ import com.jogamp.nativewindow.MutableGraphicsConfiguration;
  * <p>
  */
 public class GLEventListenerState {
-    private static final boolean DEBUG = true;
+    private static final boolean DEBUG = GLDrawableImpl.DEBUG;
     
-    private GLEventListenerState(AbstractGraphicsScreen upstreamScreen, AbstractGraphicsScreen screen, GLCapabilitiesImmutable caps, 
+    private GLEventListenerState(AbstractGraphicsScreen upstreamScreen, boolean proxyOwnsUpstreamDevice, AbstractGraphicsScreen screen, GLCapabilitiesImmutable caps, 
                                  GLContext context, int count, GLAnimatorControl anim) {
         this.upstreamScreen = upstreamScreen;
+        this.proxyOwnsUpstreamDevice = proxyOwnsUpstreamDevice;
         this.screen = screen;
         this.caps = caps;
         this.context = context;
@@ -97,6 +97,7 @@ public class GLEventListenerState {
     public final int listenerCount() { return listeners.length; }
 
     public final AbstractGraphicsScreen upstreamScreen;
+    public final boolean proxyOwnsUpstreamDevice;
     public final AbstractGraphicsScreen screen;
     public final GLCapabilitiesImmutable caps;
     public final GLContext context;
@@ -161,25 +162,30 @@ public class GLEventListenerState {
         }
         aScreen1.getDevice().clearHandleOwner();  // don't close device handle
 
-        final AbstractGraphicsScreen aUpScreen2;         
+        final AbstractGraphicsScreen aUpScreen2;
+        final boolean proxyOwnsUpstreamDevice;
         {
             AbstractGraphicsScreen _aUpScreen2=null;
             if(aSurface instanceof ProxySurface) {
                 final ProxySurface aProxy = (ProxySurface)aSurface;
+                proxyOwnsUpstreamDevice = aProxy.containsUpstreamOptionBits( ProxySurface.OPT_PROXY_OWNS_UPSTREAM_DEVICE );
                 final NativeSurface aUpSurface = aProxy.getUpstreamSurface();
-                if(null != aUpSurface) {
+                if(DEBUG && null != aUpSurface) {
                     System.err.println("X00 UpstreamSurface:            "+aUpSurface.getClass().getName()+", "+aUpSurface);
                 }
-                aProxy.clearUpstreamOptionBits( ProxySurface.OPT_PROXY_OWNS_UPSTREAM_DEVICE ); // don't close device handle
                 if(null != aUpSurface) {
                     final AbstractGraphicsScreen aUpScreen1 = aUpSurface.getGraphicsConfiguration().getScreen();
                     _aUpScreen2 = cloneScreen(aUpScreen1);
                     if(null != aUpScreen1) {
                         aUpScreen1.getDevice().clearHandleOwner(); // don't close device handle
                     }
-                    System.err.println("X0X NativeSurface:              "+aSurface.getClass().getName()+", "+aSurface);
-                    System.err.println("X0X UpstreamSurface:            "+aUpSurface.getClass().getName()+", "+aUpSurface);
+                    if(DEBUG) {
+                        System.err.println("X0X NativeSurface:              "+aSurface.getClass().getName()+", "+aSurface);
+                        System.err.println("X0X UpstreamSurface:            "+aUpSurface.getClass().getName()+", "+aUpSurface);
+                    }
                 }
+            } else {
+                proxyOwnsUpstreamDevice = false;
             }
             aUpScreen2=_aUpScreen2;
         }
@@ -189,7 +195,7 @@ public class GLEventListenerState {
             aAnim.remove(a); // also handles ECT
         }
         
-        final GLEventListenerState glls = new GLEventListenerState(aUpScreen2, aScreen2, caps, a.getContext(), aSz, aAnim); 
+        final GLEventListenerState glls = new GLEventListenerState(aUpScreen2, proxyOwnsUpstreamDevice, aScreen2, caps, a.getContext(), aSz, aAnim); 
 
         //
         // remove and cache all GLEventListener and their init-state
@@ -205,7 +211,7 @@ public class GLEventListenerState {
         //
         a.invoke(true, glFinish);
 
-        a.setContext( null );
+        a.setContext( null, false );
         
         return glls;
     }
@@ -241,13 +247,7 @@ public class GLEventListenerState {
             throw new GLException("Incompatible Capabilities - Prev-Holder: "+caps+", New-Holder "+caps);
         }
         // Destroy and remove currently associated GLContext, if any (will be replaced)
-        {
-            final GLContext ctx = a.getContext();
-            if( null != ctx) {
-                ctx.destroy();
-            }
-            a.setContext( null );
-        }
+        a.setContext( null, true );
         final boolean aRealized = a.isRealized();
         if( aRealized ) {
             a.setRealized(false);
@@ -260,8 +260,11 @@ public class GLEventListenerState {
             final AbstractGraphicsScreen aScreen1 = aCfg.getScreen();
             aCfg.setScreen( screen );
             aScreen1.getDevice().close();
-            System.err.println("XXX NativeSurface:              "+aSurface.getClass().getName()+", "+aSurface);
+            if( DEBUG ) {
+                System.err.println("XXX NativeSurface:              "+aSurface.getClass().getName()+", "+aSurface);
+            }
         }
+        
         // If using a ProxySurface w/ an upstream surface, set new Screen and close previous one on it
         {
             boolean upstreamSet = false;
@@ -270,13 +273,19 @@ public class GLEventListenerState {
                 final NativeSurface aUpSurface = aProxy.getUpstreamSurface();            
                 if(null != aUpSurface) {
                     final MutableGraphicsConfiguration aUpCfg = (MutableGraphicsConfiguration) aUpSurface.getGraphicsConfiguration();
-                    final AbstractGraphicsScreen aUpScreen1 = aUpCfg.getScreen();
                     if( null != upstreamScreen ) {
-                        System.err.println("XX0 UpstreamSurface:            "+aUpSurface.getClass().getName()+", "+aUpSurface);
+                        if( DEBUG ) {
+                            System.err.println("XX0 UpstreamSurface:            "+aUpSurface.getClass().getName()+", "+aUpSurface+", "+aProxy.getUpstreamOptionBits(null).toString());
+                        }
+                        aUpCfg.getScreen().getDevice().close();
                         aUpCfg.setScreen( upstreamScreen );
-                        aUpScreen1.getDevice().close();
+                        if( proxyOwnsUpstreamDevice ) {
+                            aProxy.addUpstreamOptionBits( ProxySurface.OPT_PROXY_OWNS_UPSTREAM_DEVICE );
+                        }
                         upstreamSet = true;
-                        System.err.println("XXX UpstreamSurface:            "+aUpSurface.getClass().getName()+", "+aUpSurface);
+                        if( DEBUG ) {
+                            System.err.println("XXX UpstreamSurface:            "+aUpSurface.getClass().getName()+", "+aUpSurface+", "+aProxy.getUpstreamOptionBits(null).toString());
+                        }
                     } else {
                         throw new GLException("Incompatible Surface config - Has Upstream-Surface: Prev-Holder = false, New-Holder = true");
                     }
@@ -292,7 +301,7 @@ public class GLEventListenerState {
         }
         final boolean surfaceLocked = false; // NativeSurface.LOCK_SURFACE_NOT_READY < aSurface.lockSurface();
         try {
-            a.setContext( context );
+            a.setContext( context, false );
         } finally {
             if( surfaceLocked ) {
                 aSurface.unlockSurface();
diff --git a/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java b/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
index 86cfa4f4c..51ec7dda6 100644
--- a/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
+++ b/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
@@ -38,6 +38,7 @@ import com.jogamp.opengl.JoglVersion;
  */
 public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
     protected static final boolean DEBUG = GLDrawableImpl.DEBUG || Debug.debug("FBObject");
+    protected static final boolean DEBUG_SWAP = Debug.isPropertyDefined("jogl.debug.FBObject.Swap", true);
     
     private final GLDrawableImpl parent;
     private GLCapabilitiesImmutable origParentChosenCaps;
@@ -92,6 +93,9 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
     }
     
     private final void initialize(boolean realize, GL gl) {
+        if( initialized == realize ) {
+            throw new InternalError("Already set to initialize := "+realize+": "+this);
+        }
         if(realize) {
             final GLCapabilities chosenFBOCaps = (GLCapabilities) getChosenGLCapabilities(); // cloned at setRealized(true)
             
@@ -323,8 +327,8 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
     }
     
     @Override
-    protected final void contextRealized(GLContext glc, boolean realized) {
-        initialize(realized, glc.getGL());
+    protected void associateContext(GLContext glc, boolean bound) {
+        initialize(bound, glc.getGL());        
     }
     
     @Override
@@ -338,7 +342,7 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
                 swapFBOImpl(glc);
                 swapFBOImplPost(glc);
                 fboBound=false;
-                if(DEBUG) {
+                if(DEBUG_SWAP) {
                     System.err.println("Post FBO swap(@release): done");
                 }
             }
@@ -354,7 +358,7 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
                 swapFBOImpl(ctx);
                 doPostSwap = true;
                 fboBound=false;
-                if(DEBUG) {
+                if(DEBUG_SWAP) {
                     System.err.println("Post FBO swap(@swap): done");
                 }
             }
@@ -406,7 +410,7 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
                 gl.glBindFramebuffer(GL2GL3.GL_READ_FRAMEBUFFER, fbos[fboIFront].getReadFramebuffer());
         } */
         
-        if(DEBUG) {
+        if(DEBUG_SWAP) {
             System.err.println("Post FBO swap(X): fboI back "+fboIBack+", front "+fboIFront+", num "+fbos.length);
         }
     }
diff --git a/src/jogl/classes/jogamp/opengl/GLPbufferImpl.java b/src/jogl/classes/jogamp/opengl/GLPbufferImpl.java
index b438131bc..ddc6d5917 100644
--- a/src/jogl/classes/jogamp/opengl/GLPbufferImpl.java
+++ b/src/jogl/classes/jogamp/opengl/GLPbufferImpl.java
@@ -86,9 +86,10 @@ public class GLPbufferImpl extends GLAutoDrawableBase implements GLPbuffer {
   // 
     
   @Override
-  public final void setRealized(boolean realized) {
+  public final void swapBuffers() throws GLException {
+      defaultSwapBuffers();
   }
-
+  
   //
   // GLAutoDrawable completion
   //
@@ -125,11 +126,6 @@ public class GLPbufferImpl extends GLAutoDrawableBase implements GLPbuffer {
     }
   }
 
-  @Override
-  public final void swapBuffers() throws GLException {
-      defaultSwapBuffers();
-  }
-  
   //----------------------------------------------------------------------
   // Internals only below this point
   //
diff --git a/src/jogl/classes/jogamp/opengl/egl/EGLUpstreamSurfaceHook.java b/src/jogl/classes/jogamp/opengl/egl/EGLUpstreamSurfaceHook.java
index 342c4c417..77e9dc173 100644
--- a/src/jogl/classes/jogamp/opengl/egl/EGLUpstreamSurfaceHook.java
+++ b/src/jogl/classes/jogamp/opengl/egl/EGLUpstreamSurfaceHook.java
@@ -47,7 +47,7 @@ public class EGLUpstreamSurfaceHook implements UpstreamSurfaceHook.MutableSize {
     public final void create(ProxySurface surface) {
         final String dbgPrefix;
         if(DEBUG) {
-            dbgPrefix = getThreadName() + ": EGLUpstreamSurfaceHook.create("+surface.getClass().getSimpleName()+"): "; 
+            dbgPrefix = getThreadName() + ": EGLUpstreamSurfaceHook.create( up "+upstreamSurface.getClass().getSimpleName()+" -> this "+surface.getClass().getSimpleName()+" ): ";
             System.err.println(dbgPrefix+this);            
         } else {
             dbgPrefix = null;
@@ -76,24 +76,51 @@ public class EGLUpstreamSurfaceHook implements UpstreamSurfaceHook.MutableSize {
         
         boolean isEGLSurfaceValid = true; // assume yes
         
-        final AbstractGraphicsConfiguration aConfig = upstreamSurface.getGraphicsConfiguration();        
-        final AbstractGraphicsDevice aDevice = aConfig.getScreen().getDevice();
-        
         final EGLGraphicsDevice eglDevice;
-        if( aDevice instanceof EGLGraphicsDevice ) {
-            eglDevice = (EGLGraphicsDevice) aDevice;
+        final AbstractGraphicsConfiguration aConfig;
+        {
+            final AbstractGraphicsConfiguration surfaceConfig = surface.getGraphicsConfiguration();
+            final AbstractGraphicsDevice surfaceDevice = null != surfaceConfig ? surfaceConfig.getScreen().getDevice() : null;
+            if(DEBUG) {
+                System.err.println(dbgPrefix+"SurfaceDevice: "+surfaceDevice.getClass().getSimpleName()+", hash 0x"+Integer.toHexString(surfaceDevice.hashCode())+", "+surfaceDevice);
+                System.err.println(dbgPrefix+"SurfaceConfig: "+surfaceConfig.getClass().getSimpleName()+", hash 0x"+Integer.toHexString(surfaceConfig.hashCode())+", "+surfaceConfig);
+            }
+    
+            final AbstractGraphicsConfiguration upstreamConfig = upstreamSurface.getGraphicsConfiguration();        
+            final AbstractGraphicsDevice upstreamDevice = upstreamConfig.getScreen().getDevice();
             if(DEBUG) {
-                System.err.println(dbgPrefix+"Reusing eglDevice: "+eglDevice);
+                System.err.println(dbgPrefix+"UpstreamDevice: "+upstreamDevice.getClass().getSimpleName()+", hash 0x"+Integer.toHexString(upstreamDevice.hashCode())+", "+upstreamDevice);
+                System.err.println(dbgPrefix+"UpstreamConfig: "+upstreamConfig.getClass().getSimpleName()+", hash 0x"+Integer.toHexString(upstreamConfig.hashCode())+", "+upstreamConfig);
             }
-            if(EGL.EGL_NO_DISPLAY == eglDevice.getHandle()) {
-                eglDevice.open();
+            
+            if( surfaceDevice instanceof EGLGraphicsDevice ) {
+                eglDevice = (EGLGraphicsDevice) surfaceDevice;
+                aConfig = surfaceConfig;
+                if(DEBUG) {
+                    System.err.println(dbgPrefix+"Reusing this eglDevice: "+eglDevice+", using this config "+aConfig.getClass().getSimpleName()+" "+aConfig);
+                }
+                if(EGL.EGL_NO_DISPLAY == eglDevice.getHandle()) {
+                    eglDevice.open();
+                    isEGLSurfaceValid = false;
+                    surface.addUpstreamOptionBits( ProxySurface.OPT_PROXY_OWNS_UPSTREAM_DEVICE );
+                }
+            } else if( upstreamDevice instanceof EGLGraphicsDevice ) {
+                eglDevice = (EGLGraphicsDevice) upstreamDevice;
+                aConfig = upstreamConfig;
+                if(DEBUG) {
+                    System.err.println(dbgPrefix+"Reusing upstream eglDevice: "+eglDevice+", using upstream config "+aConfig.getClass().getSimpleName()+" "+aConfig);
+                }
+                if(EGL.EGL_NO_DISPLAY == eglDevice.getHandle()) {
+                    eglDevice.open();
+                    isEGLSurfaceValid = false;
+                    surface.addUpstreamOptionBits( ProxySurface.OPT_PROXY_OWNS_UPSTREAM_DEVICE );
+                }
+            } else {
+                eglDevice = EGLDisplayUtil.eglCreateEGLGraphicsDevice(upstreamSurface);
+                aConfig = upstreamConfig;
                 isEGLSurfaceValid = false;
                 surface.addUpstreamOptionBits( ProxySurface.OPT_PROXY_OWNS_UPSTREAM_DEVICE );
             }
-        } else {
-            eglDevice = EGLDisplayUtil.eglCreateEGLGraphicsDevice(upstreamSurface);
-            isEGLSurfaceValid = false;
-            surface.addUpstreamOptionBits( ProxySurface.OPT_PROXY_OWNS_UPSTREAM_DEVICE );                
         }
         
         final GLCapabilitiesImmutable capsRequested = (GLCapabilitiesImmutable) aConfig.getRequestedCapabilities();
diff --git a/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLContext.java b/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLContext.java
index 3825f855c..a03850043 100644
--- a/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLContext.java
+++ b/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLContext.java
@@ -85,10 +85,9 @@ public abstract class MacOSXCGLContext extends GLContextImpl
   // NSOpenGL-based or CGL-based)
   protected interface GLBackendImpl {
         boolean isNSContext();
-        void drawableChangedNotify();
         long create(long share, int ctp, int major, int minor);
         boolean destroy(long ctx);
-        boolean contextRealized(boolean realized);
+        void associateDrawable(boolean bound);
         boolean copyImpl(long src, int mask);
         boolean makeCurrent(long ctx);
         boolean release(long ctx);
@@ -328,20 +327,15 @@ public abstract class MacOSXCGLContext extends GLContextImpl
   }
   
   @Override
-  protected void contextRealized(boolean realized) {
+  protected void associateDrawable(boolean bound) {
       // context stuff depends on drawable stuff
-      if(realized) {
-          super.contextRealized(true);   // 1) init drawable stuff
-          impl.contextRealized(true);    // 2) init context stuff
+      System.err.println("MaxOSXCGLContext.associateDrawable: "+bound);
+      if(bound) {
+          super.associateDrawable(true);   // 1) init drawable stuff
+          impl.associateDrawable(true);    // 2) init context stuff
       } else {
-          impl.contextRealized(false);   // 1) free context stuff
-          super.contextRealized(false);  // 2) free drawable stuff
-      }
-  }
-  
-  /* pp */ void drawableChangedNotify() {
-      if( 0 != contextHandle) {
-          impl.drawableChangedNotify();
+          impl.associateDrawable(false);   // 1) free context stuff
+          super.associateDrawable(false);  // 2) free drawable stuff
       }
   }
   
@@ -467,9 +461,8 @@ public abstract class MacOSXCGLContext extends GLContextImpl
 
   // NSOpenGLContext-based implementation
   class NSOpenGLImpl implements GLBackendImpl {
-      private OffscreenLayerSurface backingLayerHost = null;
-      private long nsOpenGLLayer = 0;
-      private long nsOpenGLLayerPFmt = 0; // lifecycle:  [create - contextRealized]
+      private long pixelFormat = 0; // lifecycle:  [create - destroy]
+      private long nsOpenGLLayer = 0; // lifecycle:  [associateDrawable_true - associateDrawable_false]
       private float screenVSyncTimeout; // microSec
       private int vsyncTimeout;    // microSec - for nsOpenGLLayer mode
       private int lastWidth=0, lastHeight=0; // allowing to detect size change
@@ -479,18 +472,6 @@ public abstract class MacOSXCGLContext extends GLContextImpl
       @Override
       public boolean isNSContext() { return true; }
 
-      @Override
-      public void drawableChangedNotify() {          
-          backingLayerHost = NativeWindowFactory.getOffscreenLayerSurface(drawable.getNativeSurface(), true);
-          if( null == backingLayerHost ) {
-              boolean[] isPBuffer = { false };
-              boolean[] isFBO = { false };
-              CGL.setContextView(contextHandle, getNSViewHandle(isPBuffer, isFBO));
-          } else {
-              nsOpenGLLayer = backingLayerHost.getAttachedSurfaceLayer();
-          }
-      }
-
       private long getNSViewHandle(boolean[] isPBuffer, boolean[] isFBO) {
           final long nsViewHandle;
           if(drawable instanceof GLFBODrawableImpl) {
@@ -549,13 +530,12 @@ public abstract class MacOSXCGLContext extends GLContextImpl
               isPBuffer = _isPBuffer[0];
               isFBO = _isFBO[0];
           }
-          backingLayerHost = NativeWindowFactory.getOffscreenLayerSurface(surface, true);
+          final OffscreenLayerSurface backingLayerHost = NativeWindowFactory.getOffscreenLayerSurface(surface, true);
 
           boolean incompleteView = null != backingLayerHost;
           if( !incompleteView && surface instanceof ProxySurface ) {
               incompleteView = ((ProxySurface)surface).containsUpstreamOptionBits( ProxySurface.OPT_UPSTREAM_WINDOW_INVISIBLE );
           }
-          long pixelFormat;
           {
               final GLCapabilitiesImmutable targetCaps;
               if( isFBO ) {
@@ -606,48 +586,54 @@ public abstract class MacOSXCGLContext extends GLContextImpl
           }
           config.setChosenCapabilities(fixedCaps);
           
-          try {
-              final IntBuffer viewNotReady = Buffers.newDirectIntBuffer(1);
-              // Try to allocate a context with this
-              ctx = CGL.createContext(share,
-                      nsViewHandle, incompleteView,
-                      pixelFormat,
-                      chosenCaps.isBackgroundOpaque(),
-                      viewNotReady);
-              if (0 == ctx) {
-                  if(DEBUG) {
-                      System.err.println("NS create failed: viewNotReady: "+ (1 == viewNotReady.get(0)));
-                  }
-                  return 0;
+          final IntBuffer viewNotReady = Buffers.newDirectIntBuffer(1);
+          // Try to allocate a context with this
+          ctx = CGL.createContext(share, nsViewHandle, incompleteView,
+                  pixelFormat, chosenCaps.isBackgroundOpaque(), viewNotReady);
+          if (0 == ctx) {
+              if(DEBUG) {
+                  System.err.println("NS create failed: viewNotReady: "+ (1 == viewNotReady.get(0)));
               }
+              return 0;
+          }
 
-              if(null != backingLayerHost) {
-                  nsOpenGLLayerPFmt = pixelFormat;
-                  pixelFormat = 0;
-              }
-              
-              if (chosenCaps.isOnscreen() && !chosenCaps.isBackgroundOpaque()) {
-                  // Set the context opacity
-                  CGL.setContextOpacity(ctx, 0);
-              }
-          } finally {
-              if(0!=pixelFormat) {
-                  CGL.deletePixelFormat(pixelFormat);
-                  pixelFormat = 0;
-              }
+          if (chosenCaps.isOnscreen() && !chosenCaps.isBackgroundOpaque()) {
+              // Set the context opacity
+              CGL.setContextOpacity(ctx, 0);
           }
           return ctx;
       }
 
       @Override
       public boolean destroy(long ctx) {
+          if(0!=pixelFormat) {
+              CGL.deletePixelFormat(pixelFormat);
+              pixelFormat = 0;
+          }
           return CGL.deleteContext(ctx, true);
+          
       }
 
       @Override
-      public boolean contextRealized(boolean realized) {
-          if( realized ) {
+      public void associateDrawable(boolean bound) {
+          final OffscreenLayerSurface backingLayerHost = NativeWindowFactory.getOffscreenLayerSurface(drawable.getNativeSurface(), true);
+          
+          if(DEBUG) {
+              System.err.println("MaxOSXCGLContext.NSOpenGLImpl.associateDrawable: "+bound+", ctx "+toHexString(contextHandle)+", hasBackingLayerHost "+(null!=backingLayerHost));
+          }          
+          
+          if( bound ) {
+              
               if( null != backingLayerHost ) {
+                  
+                  if( 0 != nsOpenGLLayer ) { // FIXME: redundant
+                      throw new InternalError("Lifecycle: bound=true, hasBackingLayerHost=true, but 'nsOpenGLLayer' is already/still set local: "+nsOpenGLLayer+", "+this);
+                  }
+                  nsOpenGLLayer = backingLayerHost.getAttachedSurfaceLayer();
+                  if( 0 != nsOpenGLLayer ) { // FIXME: redundant
+                      throw new InternalError("Lifecycle: bound=true, hasBackingLayerHost=true, but 'nsOpenGLLayer' is already/still set on backingLayerHost: "+nsOpenGLLayer+", "+this);
+                  }
+                  
                   //
                   // handled layered surface
                   //
@@ -700,8 +686,7 @@ public abstract class MacOSXCGLContext extends GLContextImpl
                   }
                   final boolean ctxUnlocked = CGL.kCGLNoError == CGL.CGLUnlockContext(cglCtx);
                   try {                  
-                      nsOpenGLLayer = CGL.createNSOpenGLLayer(ctx, gl3ShaderProgramName, nsOpenGLLayerPFmt, pbufferHandle, texID, chosenCaps.isBackgroundOpaque(), lastWidth, lastHeight);
-                      nsOpenGLLayerPFmt = 0; // NSOpenGLLayer will release pfmt
+                      nsOpenGLLayer = CGL.createNSOpenGLLayer(ctx, gl3ShaderProgramName, pixelFormat, pbufferHandle, texID, chosenCaps.isBackgroundOpaque(), lastWidth, lastHeight);
                       if (DEBUG) {
                           System.err.println("NS create nsOpenGLLayer "+toHexString(nsOpenGLLayer)+" w/ pbuffer "+toHexString(pbufferHandle)+", texID "+texID+", texSize "+lastWidth+"x"+lastHeight+", "+drawable);
                       }
@@ -718,17 +703,22 @@ public abstract class MacOSXCGLContext extends GLContextImpl
               } else {
                   lastWidth = drawable.getWidth();
                   lastHeight = drawable.getHeight();                  
+                  boolean[] isPBuffer = { false };
+                  boolean[] isFBO = { false };
+                  CGL.setContextView(contextHandle, getNSViewHandle(isPBuffer, isFBO));
               }
           } else {
               if( 0 != nsOpenGLLayer ) {
-                  final NativeSurface surface = drawable.getNativeSurface();
+                  if( null == backingLayerHost ) { // FIXME: redundant
+                      throw new InternalError("Lifecycle: bound=false, hasNSOpneGLLayer=true, but 'backingLayerHost' is null local: "+nsOpenGLLayer+", "+this);
+                  }
+                  
                   if (DEBUG) {
                       System.err.println("NS destroy nsOpenGLLayer "+toHexString(nsOpenGLLayer)+", "+drawable);
                   }
-                  final OffscreenLayerSurface ols = NativeWindowFactory.getOffscreenLayerSurface(surface, true);
-                  if(null != ols && ols.isSurfaceLayerAttached()) {
+                  if( backingLayerHost.isSurfaceLayerAttached() ) {
                       // still having a valid OLS attached to surface (parent OLS could have been removed)
-                      ols.detachSurfaceLayer();
+                      backingLayerHost.detachSurfaceLayer();
                   }
                   CGL.releaseNSOpenGLLayer(nsOpenGLLayer);
                   if( null != gl3ShaderProgram ) {
@@ -738,8 +728,6 @@ public abstract class MacOSXCGLContext extends GLContextImpl
                   nsOpenGLLayer = 0;
               }
           }
-          backingLayerHost = null;
-          return true;
       }
 
       private final void validatePBufferConfig(long ctx) {
@@ -889,11 +877,6 @@ public abstract class MacOSXCGLContext extends GLContextImpl
       public boolean isNSContext() { return false; }
 
       @Override
-      public void drawableChangedNotify() {
-          // FIXME
-      }
-      
-      @Override
       public long create(long share, int ctp, int major, int minor) {
           long ctx = 0;
           MacOSXCGLGraphicsConfiguration config = (MacOSXCGLGraphicsConfiguration) drawable.getNativeSurface().getGraphicsConfiguration();
@@ -947,8 +930,7 @@ public abstract class MacOSXCGLContext extends GLContextImpl
       }
 
       @Override
-      public boolean contextRealized(boolean realized) {
-          return true;
+      public void associateDrawable(boolean bound) {
       }
 
       @Override
diff --git a/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLDrawable.java b/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLDrawable.java
index ff1772860..0f282d33f 100644
--- a/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLDrawable.java
+++ b/src/jogl/classes/jogamp/opengl/macosx/cgl/MacOSXCGLDrawable.java
@@ -119,7 +119,6 @@ public abstract class MacOSXCGLDrawable extends GLDrawableImpl {
         if(bound) {
             final MacOSXCGLContext osxCtx = (MacOSXCGLContext)ctx;
             createdContexts.add(new WeakReference<MacOSXCGLContext>(osxCtx));
-            osxCtx.drawableChangedNotify();
         } else {
             for(int i=0; i<createdContexts.size(); ) {
                 final WeakReference<MacOSXCGLContext> ref = createdContexts.get(i); 
diff --git a/src/jogl/native/macosx/MacOSXWindowSystemInterface-calayer.m b/src/jogl/native/macosx/MacOSXWindowSystemInterface-calayer.m
index 2cf74380c..abc9d7958 100644
--- a/src/jogl/native/macosx/MacOSXWindowSystemInterface-calayer.m
+++ b/src/jogl/native/macosx/MacOSXWindowSystemInterface-calayer.m
@@ -275,7 +275,7 @@ static const GLfloat gl_verts[] = {
     vboBufTexCoord = 0;
     vertAttrLoc = 0;
     texCoordAttrLoc = 0;
-    parentPixelFmt = _parentPixelFmt;
+    parentPixelFmt = [_parentPixelFmt retain]; // until destruction
     swapInterval = 1; // defaults to on (as w/ new GL profiles)
     swapIntervalCounter = 0;
     timespec_now(&lastWaitTime);
@@ -338,13 +338,13 @@ static const GLfloat gl_verts[] = {
 #ifdef VERBOSE_ON
     CGRect lRect = [self bounds];
     if(NULL != pbuffer) {
-        DBG_PRINT("MyNSOpenGLLayer::init (pbuffer) %p, ctx %p, pfmt %p, pbuffer %p, opaque %d, pbuffer %dx%d -> tex %dx%d, bounds: %lf/%lf %lfx%lf (refcnt %d)\n", 
+        DBG_PRINT("MyNSOpenGLLayer::init (pbuffer) %p, ctx %p, pfmt %p, pbuffer %p, opaque %d, pbuffer %dx%d -> tex %dx%d, bounds: %lf/%lf %lfx%lf, displayLink %p (refcnt %d)\n", 
             self, parentCtx, parentPixelFmt, pbuffer, opaque, [pbuffer pixelsWide], [pbuffer pixelsHigh], texWidth, texHeight,
-            lRect.origin.x, lRect.origin.y, lRect.size.width, lRect.size.height, (int)[self retainCount]);
+            lRect.origin.x, lRect.origin.y, lRect.size.width, lRect.size.height, displayLink, (int)[self retainCount]);
     } else {
-        DBG_PRINT("MyNSOpenGLLayer::init (texture) %p, ctx %p, pfmt %p, opaque %d, tex[id %d, %dx%d], bounds: %lf/%lf %lfx%lf (refcnt %d)\n", 
+        DBG_PRINT("MyNSOpenGLLayer::init (texture) %p, ctx %p, pfmt %p, opaque %d, tex[id %d, %dx%d], bounds: %lf/%lf %lfx%lf, displayLink %p (refcnt %d)\n", 
             self, parentCtx, parentPixelFmt, opaque, (int)textureID, texWidth, texHeight,
-            lRect.origin.x, lRect.origin.y, lRect.size.width, lRect.size.height, (int)[self retainCount]);
+            lRect.origin.x, lRect.origin.y, lRect.size.width, lRect.size.height, displayLink, (int)[self retainCount]);
     }
 #endif
     return self;
@@ -498,7 +498,10 @@ static const GLfloat gl_verts[] = {
         myCtx = NULL;
     }
     parentCtx = NULL;
-    [parentPixelFmt release];
+    if( NULL != parentPixelFmt ) {
+        [parentPixelFmt release];
+        parentPixelFmt = NULL;
+    }
     pthread_mutex_unlock(&renderLock);
     [self release];
     DBG_PRINT("MyNSOpenGLLayer::releaseLayer.X: %p\n", self);
@@ -623,7 +626,7 @@ static const GLfloat gl_verts[] = {
 {
     DBG_PRINT("MyNSOpenGLLayer::openGLPixelFormatForDisplayMask: %p (refcnt %d) - parent-pfmt %p -> new-pfmt %p\n", 
         self, (int)[self retainCount], parentPixelFmt, parentPixelFmt);
-    // We simply take over ownership of parent PixelFormat ..
+    // We simply take over ownership of parent PixelFormat until releaseLayer..
     return parentPixelFmt;
 }