Bug 776 GLContext Sharing: Refine API for relaxed and lazy GLContext sharing ; Fix GLContext memory contract (volatile)

(Unit test remarks see below)

- Add shared GLContext queries
  - Refined GLContextShareSet:
    - Use IdentityHashMap since GLContext's can only be identical w/ same reference (footprint, performance)
    - Add API doc for clarification
    - Add methods:
       - ArrayList<GLContext> getCreatedShares(final GLContext context)
       - ArrayList<GLContext> getDestroyedShares(final GLContext context)
    - Use 'final' where possible

  - Add GLContext methods:
      - boolean isShared()
      - List<GLContext> getCreatedShares()
      - List<GLContext> getDestroyedShares()

- Add GLSharedContextSetter interface defining setting a shared GLContext
  directly (GLContext) or via a GLAutoDrawable:
  - setSharedContext(GLContext)
  - setSharedAutoDrawable(GLAutoDrawable)

  Both cause initialization/creation of GLAutoDrawable's drawable/context to be postponed,
  if the shared GLContext is not yet created natively or
  the shared GLAutoDrawable's GLContext does not yet exist.

  Most of impl. resides in GLDrawableHelper

  Implemented in:
    - GLAutoDrawableBase, GLOffscreenAutoDrawable
    - GLWindow
    - AWT GLCanvas

  TODO:
    - GLJPanel
    - SWT GLCanvas

- GLDrawableFactory:
   - Add 'GLOffscreenAutoDrawable createOffscreenAutoDrawable(..)' variant w/o passing the
     optional shared GLContext _and_ specifying lazy GLContext
     creation. This allows to benefit from GLSharedContextSetter contract.
     Lazy GLContext creation is performed at 2st display() call at the latest.

     All JOGL code and unit tests use this new method now.

  - Mark 'createOffscreenAutoDrawable(..)' w/ shared GLContext argument
    and immediate GLContext creation deprecated - shall be removed in 2.2.0

- Make reference to GLContext and it's native handle volatile
  Since we rely on the query 'GLContext.isCreated()' to properly allow GLAutoDrawable's to query whether
  a shared GLContext is natively created (already), the handle must be volatile
  since such query and the actual creation may operate on different threads.

+++++

- Add/Refine shared GLContext unit tests demonstrating diff. sharing methods.

  All variants of using shared GLContext:
      com.jogamp.opengl.test.junit.jogl.acore.TestSharedContextVBO*

  Most convenient way to share via setSharedAutoDrawable(GLAutoDrawable):
      com.jogamp.opengl.test.junit.jogl.acore.TestSharedContextVBOES2[NEWT|AWT]3

  AWT use w/ JTabbedPane using setSharedAutoDrawable(GLAutoDrawable):
      com.jogamp.opengl.test.junit.jogl.acore.TestSharedContextWithJTabbedPaneAWT

2 files changed, 20 insertions, 32 deletions

diff --git a/src/newt/classes/com/jogamp/newt/awt/NewtCanvasAWT.java b/src/newt/classes/com/jogamp/newt/awt/NewtCanvasAWT.java
index 1f5c26f27..70157fe4b 100644
--- a/src/newt/classes/com/jogamp/newt/awt/NewtCanvasAWT.java
+++ b/src/newt/classes/com/jogamp/newt/awt/NewtCanvasAWT.java
@@ -105,7 +105,7 @@ public class NewtCanvasAWT extends java.awt.Canvas implements WindowClosingProto
     private AWTAdapter awtMouseAdapter = null;
     private AWTAdapter awtKeyAdapter = null;
 
-    private AWTWindowClosingProtocol awtWindowClosingProtocol =
+    private final AWTWindowClosingProtocol awtWindowClosingProtocol =
           new AWTWindowClosingProtocol(this, new Runnable() {
                 @Override
                 public void run() {
@@ -204,7 +204,7 @@ public class NewtCanvasAWT extends java.awt.Canvas implements WindowClosingProto
             return false; // NEWT shall proceed requesting the native focus
         }
     }
-    private FocusAction focusAction = new FocusAction();
+    private final FocusAction focusAction = new FocusAction();
 
     WindowListener clearAWTMenusOnNewtFocus = new WindowAdapter() {
           @Override
@@ -559,8 +559,7 @@ public class NewtCanvasAWT extends java.awt.Canvas implements WindowClosingProto
                 final GLDrawableFactory factory = GLDrawableFactory.getFactory(caps.getGLProfile());
                 printGLAD = factory.createOffscreenAutoDrawable(null, caps, null,
                         printAWTTiles.customTileWidth != -1 ? printAWTTiles.customTileWidth : DEFAULT_PRINT_TILE_SIZE,
-                        printAWTTiles.customTileHeight != -1 ? printAWTTiles.customTileHeight : DEFAULT_PRINT_TILE_SIZE,
-                        null);
+                        printAWTTiles.customTileHeight != -1 ? printAWTTiles.customTileHeight : DEFAULT_PRINT_TILE_SIZE);
                 GLDrawableUtil.swapGLContextAndAllGLEventListener(glad, printGLAD);
                 printDrawable = printGLAD.getDelegatedDrawable();
             }
diff --git a/src/newt/classes/com/jogamp/newt/opengl/GLWindow.java b/src/newt/classes/com/jogamp/newt/opengl/GLWindow.java
index 8c1110ed3..4f259fe9a 100644
--- a/src/newt/classes/com/jogamp/newt/opengl/GLWindow.java
+++ b/src/newt/classes/com/jogamp/newt/opengl/GLWindow.java
@@ -499,21 +499,24 @@ public class GLWindow extends GLAutoDrawableBase implements GLAutoDrawable, Wind
                 if( ( null != context ) ) {
                     throw new InternalError("GLWindow.LifecycleHook.setVisiblePost: "+WindowImpl.getThreadName()+" - Null drawable, but valid context - "+GLWindow.this);
                 }
-                final NativeSurface ns;
-                {
-                    final NativeSurface wrapped_ns = window.getWrappedSurface();
-                    ns = null != wrapped_ns ? wrapped_ns : window;
-                }
-                final GLCapabilitiesImmutable glCaps = (GLCapabilitiesImmutable) ns.getGraphicsConfiguration().getChosenCapabilities();
-                if(null==factory) {
-                    factory = GLDrawableFactory.getFactory(glCaps.getGLProfile());
-                }
-                drawable = (GLDrawableImpl) factory.createGLDrawable(ns);
-                drawable.setRealized(true);
+                final GLContext[] shareWith = { null };
+                if( !helper.isSharedGLContextPending(shareWith) ) {
+                    final NativeSurface ns;
+                    {
+                        final NativeSurface wrapped_ns = window.getWrappedSurface();
+                        ns = null != wrapped_ns ? wrapped_ns : window;
+                    }
+                    final GLCapabilitiesImmutable glCaps = (GLCapabilitiesImmutable) ns.getGraphicsConfiguration().getChosenCapabilities();
+                    if(null==factory) {
+                        factory = GLDrawableFactory.getFactory(glCaps.getGLProfile());
+                    }
+                    drawable = (GLDrawableImpl) factory.createGLDrawable(ns);
+                    drawable.setRealized(true);
 
-                if( !GLWindow.this.pushGLEventListenerState() ) {
-                    context = (GLContextImpl) drawable.createContext(sharedContext);
-                    context.setContextCreationFlags(additionalCtxCreationFlags);
+                    if( !GLWindow.this.restoreGLEventListenerState() ) {
+                        context = (GLContextImpl) drawable.createContext(shareWith[0]);
+                        context.setContextCreationFlags(additionalCtxCreationFlags);
+                    }
                 }
             }
             if(Window.DEBUG_IMPLEMENTATION) {
@@ -573,25 +576,11 @@ public class GLWindow extends GLAutoDrawableBase implements GLAutoDrawable, Wind
     // OpenGL-related methods and state
     //
 
-    private GLContext sharedContext = null;
-
     @Override
     protected final RecursiveLock getLock() {
         return window.getLock();
     }
 
-    /**
-     * Specifies an {@link javax.media.opengl.GLContext OpenGL context} to share with.<br>
-     * At native creation, {@link #setVisible(boolean) setVisible(true)},
-     * a {@link javax.media.opengl.GLDrawable drawable} and {@link javax.media.opengl.GLContext context} is created besides the native Window itself,<br>
-     * hence you shall set the shared context before.
-     *
-     * @param sharedContext The OpenGL context shared by this GLWindow's one
-     */
-    public void setSharedContext(GLContext sharedContext) {
-        this.sharedContext = sharedContext;
-    }
-
     @Override
     public void display() {
         if( !isNativeValid() || !isVisible() ) { return; }