Seamless Integration of an FBObject based GLFBODrawable as GLOffscreenAutoDrawable.FBO and as an OffscreenLayerSurface's drawable (OSX) - Fix Bugs 569 and 599

Summary:
=========
The new FBObject based GLFBODrawable implementation allows the seamless utilization of
FBO offscreen rendering in single buffer, double buffer and MSAA mode.

The GLFBODrawable uses a parent drawable based on a
dummy surface to allow a GLOffscreenAutoDrawable.FBO creation
or a mutable surface supporting an existing offscreen layer surface (OSX CALayer).

Offscreen GLDrawable's and GLOffscreenAutoDrawable's can be selected via the
GLCapabilities. If simply !onscreen is selected in the caps instance w/o enabling FBO, PBuffer or Bitmap,
the factory will automatically choose regarding availability:
   FBO > PBuffer > Bitmap

Double buffering is supported in MSAA more (intrinsic) and explicit in non MSAA.
It is preferred when delivering resources (texture id's or framebuffer names)
to a shared GLContext.
This is demonstrated in (emulates our OSX CALayer implementation):
  TestFBOOffThreadSharedContextMix2DemosES2NEWT,
  TestFBOOnThreadSharedContext1DemoES2NEWT
and with the OSX JAWT OffscreenLayerSurface itself. FBO is the preferred choice.

+++

Offscreen drawables can be resized while maintaining a bound GLContext (e.g. w/ GLAutoDrawable).
Previously both, drawable and context, needed to be destroyed and recreated at offscreen resize.
Common implementation in GLDrawableHelper is used in the implementations
(NEWT's GLWindow, AWT GLCanvas, SWT GLCanvas).

+++

Tested:
=======

Manually run all unit tests on:
  - Linux x86_64 NVidia/AMD/Mesa3d(ES)
  - OSX x86_64 NVidia
  - Windows x86_64 NVidia
  - Android arm Mali-400/Tegra-2

No regressions.

Disclaimer:
===========
This feature is committed almost in one patch.

Both previous commits were introducing / fixing the capabilities behavior:
 90d45928186f2be99999461cfe45f76a783cc961
 9036376b7806a5fc61590bf49404eb71830de92f

I have to appologize for the huge size and impact (files and platforms) of this commit
however, I could not find a better way to inject this feature in one sane piece.

NativeWindow Details:
=====================

Complete decoupling of platform impl. detail of surfaces
implementing ProxySurface. Used to generalize dummy surfaces and EGL surfaces
on top of a native platform surface.
  - ProxySurface.UpstreamSurfaceHook -> UpstreamSurfaceHook
  - abstract class ProxySurface -> interface ProxySurface + ProxySurfaceImpl
  - Misc. implementations

JOGL Details:
=====================

FBOObject: API Change / Simplification & Usability
  - Removed reference counter to remove complexity, allow user to choose.
  - Add 'dispose' flag for detachColorbuffer(..), allowing to keep attachment alive
  - Fix equals operation of Attachment
  - Check pre-exising GL errors
  - Interface Colobuffer gets lifecycle methods
  - Add static factory methods to create Attachments w/o FBObject instance
  - Reset:
    - Clip min size to 1
    - Keep alive samplingSink, i.e. don't issue resetMSAATexture2DSink(..).
      It gets called at syncFramebuffer()/use(..) later on before actual usage.
      This allows the consumer to utilize the GL_FRONT buffer until (e.g.) swap.
  - misc bugfixes

GLOffscreenAutoDrawable: API Change
  - Reloc and interfacing
  - class com.jogamp.opengl.OffscreenAutoDrawable -> javax.media.opengl.*
    interfaces GLOffscreenAutoDrawable extends GLAutoDrawable
               GLOffscreenAutoDrawable.FBO extends GLOffscreenAutoDrawable, GLFBODrawable
  - Added general implementation and FBO specialization
  - Replacing GLPBuffer (deprecated) .. usable for any offscreen GLDrawable via factory

GLAutoDrawable:
  - Add 'GLDrawable getDelegatedDrawable()'
  - Refine documentation of setContext(..), remove disclaimer and fixme tags

GLDrawableFactory:
  - Refine API doc and it's selection mechanism for offscreen.
  - Add createOffscreenDrawable(..)
  - Add createOffscreenAutoDrawable(..)
  - Add canCreateFBO(..)
  - Mark createGLPbuffer(..) deprectated

Mark GLPBuffer deprecated

New: GLFBODrawable extends GLDrawable

GLCanvas (AWT and SWT): Add offscreen resize support w/o GLContext recreation

GLAutoDrawableBase .. GLWindow:
  - Add offscreen resize support w/o GLContext recreation
  - Remove double swapBuffer call
  -

GLBase/GLContext:
  - Add:
    - boolean hasBasicFBOSupport()
    - boolean hasFullFBOSupport()
    - int getMaxRenderbufferSamples()
    - boolean isTextureFormatBGRA8888Available()

GLContext: Fix version detection and hasGLSL()
  - Version detection in setGLFunctionAvailability(..)
    - Query GL_VERSION ASAP and parse it and compare w/ given major/minor
    - Use parsed version if valid and lower than given _or_ given is invalid.
    - Use validated version for caching (procaddr, ..), version number, etc.

  - Fix hasGLSL()
    Since 'isGL2ES2()' is true if 'isGL2()'
    and the latter simply alows GL 1.*, we confine the result to a GL >= 2.0
    on desktops. FIXME: May consider GL 1.5 w/ extensions.
    -  return isGL2ES2();
    +      return isGLES2() ||
    +             isGL3() ||
    +             isGL2() && ctxMajorVersion>1 ;

GLDrawableImpl:
  - Add 'associateContext(GLContext, boolean)' allowing impl.
    to have a (weak) reference list of bound context.
    This is was pulled up from the OSX specific drawable impl.
  - swapBuffersImpl() -> swapBuffersImpl(boolean doubleBuffered)
    and call it regardless of single buffering.
    This is required to propagate this event to impl. properly,
    i.e. FBODrawable requires a swap notification.
  - Clarify 'contextMadeCurrent(..)' protocol

GLDrawableHelper:
  - Add resize and recreate offscreen drawable util method
  - Simplify required init/reshape calls for GLEventListener
  -

GLGraphicsConfigurationUtil:
  - fixWinAttribBitsAndHwAccel: Reflect sharede context hw-accel bits
  - OSX has no offscreen bitmap, use pbuffer
  - use proper offscreen auto selection if offscreen and no modes are set

EGL Context/Drawable/DrawableFactory: Abstract native platform code out of base classes
  - Use EGLWrappedSurface w/ UpstreamSurfaceHook to handle upstream (X11, WGL, ..)
    lifecycle - in case the EGL resource is hooked up on it.

Invisible dummy surfaces: All platforms
  - size is now reduced to 64x64 and decoupled of actual generic mutable size
  - fix device  lifecycle, no more leaks

+++

OSX
====

Enable support for GLFBODrawableImpl in offscreen CALayer mode
  - NSOpenGLImpl: hooks to calayer native code
  - calayer code:
    - allows pbuffer and texures (FBO)
    - decouple size and draw calls avoiding flickering
    - enable auto resize of calayer tree

MacOSXCGLContext:
  - NSOpenGLImpl:
  - Fix false pbuffer 'usage', validate the pointer
  - If !pbuffer, copy other window mode bits of caps
  -

MacOSXCGLGraphicsConfiguration:
  - Only assume pbuffer if !onscreen
  - Remove reference of native pixelformat pointer

Native code:
  - use 'respondsToSelector:' query before calling 'new' methods
    avoiding an error message where unsuported (prev. OSX versions)
  - if monitor refresh-rate is queried 0, set to default 60hz
  - add missing NSAutoreleasePool decoration

+++

Android / NEWT:
===============

Issue setVisible(..) w/o wait, i.e. queue on EDT,
@Android surfaceChanged() callback. Otherwise we could deadlock:
   setVisible(..) -> EDT -> setVisibleImpl(..) -> 'GL-display'.
the latter may may cause havoc while Android-EDT is blocked [until it's return].

7 files changed, 29 insertions, 79 deletions

diff --git a/src/jogl/classes/jogamp/opengl/x11/glx/X11ExternalGLXContext.java b/src/jogl/classes/jogamp/opengl/x11/glx/X11ExternalGLXContext.java
index 1f3edbd8a..03a0eefbf 100644
--- a/src/jogl/classes/jogamp/opengl/x11/glx/X11ExternalGLXContext.java
+++ b/src/jogl/classes/jogamp/opengl/x11/glx/X11ExternalGLXContext.java
@@ -48,10 +48,10 @@ import javax.media.opengl.GLDrawableFactory;
 import javax.media.opengl.GLException;
 import javax.media.opengl.GLProfile;
 
+import jogamp.nativewindow.WrappedSurface;
 import jogamp.opengl.GLContextImpl;
 import jogamp.opengl.GLContextShareSet;
 
-import com.jogamp.nativewindow.WrappedSurface;
 import com.jogamp.nativewindow.x11.X11GraphicsScreen;
 
 public class X11ExternalGLXContext extends X11GLXContext {
@@ -105,7 +105,7 @@ public class X11ExternalGLXContext extends X11GLXContext {
         cfg = X11GLXGraphicsConfiguration.create(glp, x11Screen, val[0]);
     }
 
-    final WrappedSurface ns = new WrappedSurface(cfg, drawable, w, h, null);
+    final WrappedSurface ns = new WrappedSurface(cfg, drawable, w, h, true);
     return new X11ExternalGLXContext(new Drawable(factory, ns), ctx);
   }
 
diff --git a/src/jogl/classes/jogamp/opengl/x11/glx/X11ExternalGLXDrawable.java b/src/jogl/classes/jogamp/opengl/x11/glx/X11ExternalGLXDrawable.java
index 8652e2d4a..ac78c6f4a 100644
--- a/src/jogl/classes/jogamp/opengl/x11/glx/X11ExternalGLXDrawable.java
+++ b/src/jogl/classes/jogamp/opengl/x11/glx/X11ExternalGLXDrawable.java
@@ -45,7 +45,8 @@ import javax.media.opengl.GLDrawableFactory;
 import javax.media.opengl.GLException;
 import javax.media.opengl.GLProfile;
 
-import com.jogamp.nativewindow.WrappedSurface;
+import jogamp.nativewindow.WrappedSurface;
+
 import com.jogamp.nativewindow.x11.X11GraphicsScreen;
 
 
@@ -87,7 +88,7 @@ public class X11ExternalGLXDrawable extends X11GLXDrawable {
         System.err.println("X11ExternalGLXDrawable: WARNING: forcing GLX_RGBA_TYPE for newly created contexts (current 0x"+Integer.toHexString(val[0])+")");
       }
     }
-    return new X11ExternalGLXDrawable(factory, new WrappedSurface(cfg, drawable, w, h, null));
+    return new X11ExternalGLXDrawable(factory, new WrappedSurface(cfg, drawable, w, h, true));
   }
 
   @Override
diff --git a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXDrawable.java b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXDrawable.java
index e9912ce9d..8c642777d 100644
--- a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXDrawable.java
+++ b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXDrawable.java
@@ -69,9 +69,10 @@ public abstract class X11GLXDrawable extends GLDrawableImpl {
   }
 
   @Override
-  protected final void swapBuffersImpl() {
-    // single-buffer is already filtered out @ GLDrawableImpl#swapBuffers()
-    GLX.glXSwapBuffers(getNativeSurface().getDisplayHandle(), getHandle());
+  protected final void swapBuffersImpl(boolean doubleBuffered) {
+    if(doubleBuffered) {
+        GLX.glXSwapBuffers(getNativeSurface().getDisplayHandle(), getHandle());
+    }
   }
 
   //---------------------------------------------------------------------------
diff --git a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXDrawableFactory.java b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXDrawableFactory.java
index bc3e5b793..fb11f8bba 100644
--- a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXDrawableFactory.java
+++ b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXDrawableFactory.java
@@ -49,7 +49,7 @@ import javax.media.nativewindow.AbstractGraphicsScreen;
 import javax.media.nativewindow.NativeSurface;
 import javax.media.nativewindow.NativeWindowFactory;
 import javax.media.nativewindow.ProxySurface;
-import javax.media.nativewindow.ProxySurface.UpstreamSurfaceHook;
+import javax.media.nativewindow.UpstreamSurfaceHook;
 import javax.media.nativewindow.VisualIDHolder;
 import javax.media.opengl.GLCapabilities;
 import javax.media.opengl.GLCapabilitiesChooser;
@@ -59,6 +59,8 @@ import javax.media.opengl.GLDrawable;
 import javax.media.opengl.GLException;
 import javax.media.opengl.GLProfile;
 
+import jogamp.nativewindow.WrappedSurface;
+import jogamp.nativewindow.x11.X11DummyUpstreamSurfaceHook;
 import jogamp.nativewindow.x11.X11Lib;
 import jogamp.nativewindow.x11.X11Util;
 import jogamp.opengl.DesktopGLDynamicLookupHelper;
@@ -70,7 +72,6 @@ import jogamp.opengl.GLGraphicsConfigurationUtil;
 import jogamp.opengl.SharedResourceRunner;
 
 import com.jogamp.common.util.VersionNumber;
-import com.jogamp.nativewindow.WrappedSurface;
 import com.jogamp.nativewindow.x11.X11GraphicsDevice;
 import com.jogamp.nativewindow.x11.X11GraphicsScreen;
 
@@ -505,7 +506,7 @@ public class X11GLXDrawableFactory extends GLDrawableFactoryImpl {
   protected final ProxySurface createMutableSurfaceImpl(AbstractGraphicsDevice deviceReq, boolean createNewDevice, 
                                                         GLCapabilitiesImmutable capsChosen,
                                                         GLCapabilitiesImmutable capsRequested,
-                                                        GLCapabilitiesChooser chooser, int width, int height, UpstreamSurfaceHook lifecycleHook) {
+                                                        GLCapabilitiesChooser chooser, UpstreamSurfaceHook upstreamHook) {
     final X11GraphicsDevice device;
     if(createNewDevice) {
         // Null X11 locking, due to private non-shared Display handle
@@ -518,65 +519,15 @@ public class X11GLXDrawableFactory extends GLDrawableFactoryImpl {
     if(null == config) {
         throw new GLException("Choosing GraphicsConfiguration failed w/ "+capsChosen+" on "+screen); 
     }
-    return new WrappedSurface( config, 0, width, height, lifecycleHook);
+    return new WrappedSurface(config, 0, upstreamHook, createNewDevice);
   }
 
   @Override
   public final ProxySurface createDummySurfaceImpl(AbstractGraphicsDevice deviceReq, boolean createNewDevice, 
                                                    GLCapabilitiesImmutable requestedCaps, GLCapabilitiesChooser chooser, int width, int height) {
     final GLCapabilitiesImmutable chosenCaps = GLGraphicsConfigurationUtil.fixOnscreenGLCapabilities(requestedCaps);
-    return createMutableSurfaceImpl(deviceReq, createNewDevice, chosenCaps, requestedCaps, chooser, width, height, dummySurfaceLifecycleHook); 
+    return createMutableSurfaceImpl(deviceReq, createNewDevice, chosenCaps, requestedCaps, chooser, new X11DummyUpstreamSurfaceHook(width, height)); 
   }  
-  private static final ProxySurface.UpstreamSurfaceHook dummySurfaceLifecycleHook = new ProxySurface.UpstreamSurfaceHook() {
-    @Override
-    public final void create(ProxySurface s) {
-        if( 0 == s.getSurfaceHandle() ) {
-            final X11GLXGraphicsConfiguration cfg = (X11GLXGraphicsConfiguration) s.getGraphicsConfiguration();
-            final X11GraphicsScreen screen = (X11GraphicsScreen) cfg.getScreen();
-            final X11GraphicsDevice device = (X11GraphicsDevice) screen.getDevice();
-            if(0 == device.getHandle()) {
-                device.open();
-                s.setImplBitfield(ProxySurface.OWN_DEVICE);
-            }
-            final long windowHandle = X11Lib.CreateDummyWindow(device.getHandle(), screen.getIndex(), cfg.getXVisualID(), s.getWidth(), s.getHeight());
-            if(0 == windowHandle) {
-                throw new GLException("Creating dummy window failed w/ "+cfg+", "+s.getWidth()+"x"+s.getHeight());
-            }
-            s.setSurfaceHandle(windowHandle);
-            if(DEBUG) {
-                System.err.println("X11GLXDrawableFactory.dummySurfaceLifecycleHook.create: "+s);
-            }
-        }
-    }
-    @Override
-    public final void destroy(ProxySurface s) {
-        if(0 != s.getSurfaceHandle()) {
-            final X11GLXGraphicsConfiguration config = (X11GLXGraphicsConfiguration) s.getGraphicsConfiguration();
-            final X11GraphicsDevice device = (X11GraphicsDevice) config.getScreen().getDevice();
-            X11Lib.DestroyDummyWindow(device.getHandle(), s.getSurfaceHandle());            
-            s.setSurfaceHandle(0);
-            if( 0 != ( ProxySurface.OWN_DEVICE & s.getImplBitfield() ) ) {
-                device.close();
-            }
-            if(DEBUG) {
-                System.err.println("X11GLXDrawableFactory.dummySurfaceLifecycleHook.destroy: "+s);
-            }
-        }
-    }
-    @Override
-    public final int getWidth(ProxySurface s) {
-        return s.initialWidth;
-    }
-    @Override
-    public final int getHeight(ProxySurface s) {
-        return s.initialHeight;
-    }
-    @Override
-    public String toString() {
-       return "X11SurfaceLifecycleHook[]";
-    }
-  };
-  
   
   @Override
   protected final ProxySurface createProxySurfaceImpl(AbstractGraphicsDevice deviceReq, int screenIdx, long windowHandle, GLCapabilitiesImmutable capsRequested, GLCapabilitiesChooser chooser, UpstreamSurfaceHook upstream) {
@@ -593,7 +544,7 @@ public class X11GLXDrawableFactory extends GLDrawableFactoryImpl {
     if(DEBUG) {
         System.err.println("X11GLXDrawableFactory.createProxySurfaceImpl 0x"+Long.toHexString(windowHandle)+": "+cfg);
     }
-    return new WrappedSurface(cfg, windowHandle, 0, 0, upstream);
+    return new WrappedSurface(cfg, windowHandle, upstream, true);
   }
 
   @Override
diff --git a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXGraphicsConfiguration.java b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXGraphicsConfiguration.java
index 866fcbbe4..96c3c4123 100644
--- a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXGraphicsConfiguration.java
+++ b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXGraphicsConfiguration.java
@@ -307,7 +307,7 @@ public class X11GLXGraphicsConfiguration extends X11GraphicsConfiguration implem
       return null; // no RGBA -> color index not supported
     }
 
-    X11GLCapabilities res = new X11GLCapabilities(visualInfo, fbcfg, fbcfgid, glp);
+    final X11GLCapabilities res = new X11GLCapabilities(visualInfo, fbcfg, fbcfgid, glp);
     if (isMultisampleAvailable) {
       res.setSampleBuffers(glXGetFBConfig(display, fbcfg, GLX.GLX_SAMPLE_BUFFERS, tmp, 0) != 0);
       res.setNumSamples   (glXGetFBConfig(display, fbcfg, GLX.GLX_SAMPLES,        tmp, 0));
@@ -342,7 +342,7 @@ public class X11GLXGraphicsConfiguration extends X11GraphicsConfiguration implem
         res.setPbufferFloatingPointBuffers(glXGetFBConfig(display, fbcfg, GLXExt.GLX_FLOAT_COMPONENTS_NV, tmp, 0) != GL.GL_FALSE);
     } catch (Exception e) {}
 
-    return (X11GLCapabilities) GLGraphicsConfigurationUtil.setWinAttributeBits(res, drawableTypeBits);
+    return (X11GLCapabilities) GLGraphicsConfigurationUtil.fixWinAttribBitsAndHwAccel(device, drawableTypeBits, res); 
   }
 
   private static String glXGetFBConfigErrorCode(int err) {
@@ -462,7 +462,7 @@ public class X11GLXGraphicsConfiguration extends X11GraphicsConfiguration implem
     res.setAccumBlueBits (glXGetConfig(display, info, GLX.GLX_ACCUM_BLUE_SIZE,  tmp, 0));
     res.setAccumAlphaBits(glXGetConfig(display, info, GLX.GLX_ACCUM_ALPHA_SIZE, tmp, 0));
 
-    return (X11GLCapabilities) GLGraphicsConfigurationUtil.setWinAttributeBits(res, drawableTypeBits);
+    return (X11GLCapabilities) GLGraphicsConfigurationUtil.fixWinAttribBitsAndHwAccel(device, drawableTypeBits, res); 
   }
 
   private static String glXGetConfigErrorCode(int err) {
diff --git a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXGraphicsConfigurationFactory.java b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXGraphicsConfigurationFactory.java
index 8086cd26a..431706e24 100644
--- a/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXGraphicsConfigurationFactory.java
+++ b/src/jogl/classes/jogamp/opengl/x11/glx/X11GLXGraphicsConfigurationFactory.java
@@ -129,9 +129,7 @@ public class X11GLXGraphicsConfigurationFactory extends GLGraphicsConfigurationF
         }
         final X11GraphicsScreen sharedScreen = (X11GraphicsScreen) sharedResource.getScreen();
         final boolean isMultisampleAvailable = factory.isGLXMultisampleAvailable(sharedScreen.getDevice());
-        final X11GLXDrawable sharedDrawable = (X11GLXDrawable) sharedResource.getDrawable();
-        final GLCapabilitiesImmutable capsChosen = sharedDrawable.getChosenGLCapabilities();
-        final GLProfile glp = capsChosen.getGLProfile();
+        final GLProfile glp = GLProfile.getDefault(device);
 
         List<GLCapabilitiesImmutable> availableCaps = null;
 
@@ -217,7 +215,7 @@ public class X11GLXGraphicsConfigurationFactory extends GLGraphicsConfigurationF
         X11GLXDrawableFactory factory = (X11GLXDrawableFactory) GLDrawableFactory.getDesktopFactory();
 
         capsChosen = GLGraphicsConfigurationUtil.fixGLCapabilities( capsChosen, GLContext.isFBOAvailable(x11Device, capsChosen.getGLProfile()), factory.canCreateGLPbuffer(x11Device) );
-        boolean usePBuffer = capsChosen.isPBuffer();
+        boolean usePBuffer = !capsChosen.isOnscreen() && capsChosen.isPBuffer();
     
         X11GLXGraphicsConfiguration res = null;
         if( factory.isGLXVersionGreaterEqualOneThree(x11Device) ) {
diff --git a/src/jogl/classes/jogamp/opengl/x11/glx/X11PbufferGLXDrawable.java b/src/jogl/classes/jogamp/opengl/x11/glx/X11PbufferGLXDrawable.java
index e1fe2f27e..bba2b3513 100644
--- a/src/jogl/classes/jogamp/opengl/x11/glx/X11PbufferGLXDrawable.java
+++ b/src/jogl/classes/jogamp/opengl/x11/glx/X11PbufferGLXDrawable.java
@@ -81,10 +81,11 @@ public class X11PbufferGLXDrawable extends X11GLXDrawable {
   }
 
   private void createPbuffer() {
-      X11GLXGraphicsConfiguration config = (X11GLXGraphicsConfiguration) getNativeSurface().getGraphicsConfiguration();
-      AbstractGraphicsScreen aScreen = config.getScreen();
-      AbstractGraphicsDevice aDevice = aScreen.getDevice();
-      long display = aDevice.getHandle();
+      final MutableSurface ms = (MutableSurface) getNativeSurface();
+      final X11GLXGraphicsConfiguration config = (X11GLXGraphicsConfiguration) ms.getGraphicsConfiguration();
+      final AbstractGraphicsScreen aScreen = config.getScreen();
+      final AbstractGraphicsDevice aDevice = aScreen.getDevice();
+      final long display = aDevice.getHandle();
 
       if (DEBUG) {
         System.out.println("Pbuffer config: " + config);
@@ -94,8 +95,6 @@ public class X11PbufferGLXDrawable extends X11GLXDrawable {
         throw new GLException("Null display");
       }
 
-      NativeSurface ns = getNativeSurface();
-
       GLCapabilitiesImmutable chosenCaps = (GLCapabilitiesImmutable)config.getChosenCapabilities();
 
       if (chosenCaps.getPbufferRenderToTexture()) {
@@ -111,9 +110,9 @@ public class X11PbufferGLXDrawable extends X11GLXDrawable {
       int[] iattributes = new int[7];
 
       iattributes[niattribs++] = GLX.GLX_PBUFFER_WIDTH;
-      iattributes[niattribs++] = ns.getWidth();
+      iattributes[niattribs++] = ms.getWidth();
       iattributes[niattribs++] = GLX.GLX_PBUFFER_HEIGHT;
-      iattributes[niattribs++] = ns.getHeight();
+      iattributes[niattribs++] = ms.getHeight();
       iattributes[niattribs++] = GLX.GLX_LARGEST_PBUFFER; // exact
       iattributes[niattribs++] = 0;
       iattributes[niattribs++] = 0;
@@ -125,7 +124,7 @@ public class X11PbufferGLXDrawable extends X11GLXDrawable {
       }
 
       // Set up instance variables
-      ((MutableSurface)ns).setSurfaceHandle(pbuffer);
+      ms.setSurfaceHandle(pbuffer);
 
       if (DEBUG) {
         System.err.println("Created pbuffer " + this);