Bug 1068 - Allow GLContext creation and makeCurrent without default framebuffer (Part 2); Bug 896: EGL_KHR_create_context (Part 1)

Bug 1068 - Allow GLContext creation and makeCurrent without default framebuffer (Part 2)

Implement surfaceless context on EGL and GLX/X11
utilizing *UpstreamSurfacelessHook as introduced in
commit 9ea218a5990b908e04235c407c0951c60df6ffba.

Surfaceless context is probed during GL profile probing by default.
If available, it will be used for offscreen FBO drawables.
If probing fails, or is disabled,
the new GLRendererQuirks.NoSurfacelessCtx is set.

- GLProfile.disableSurfacelessContext disables
  surfaceless context probing, set property 'jogl.disable.surfacelesscontext'

Tested:
  - Mesa/EGL works,
  - Mesa + NVidia w/ GLX fail on GNU/Linux): Fails NoSurfacelessCtx

- TODO: Windows impl. and more tests

+++

Bug 896: EGL_KHR_create_context (Part 1)

- Detect EGL_KHR_create_context capability and utilize if available.

- Implement EGLContext.createContextARBImpl(..),
  allowing native DEBUG context usage, where available.

- EGL implements SharedResourceRunner, i.e. probing profiles
  on dedicated thread using common interface.

- Probe desktop profile/context ability
  in EGLDrawableFactory SharedResourceRunner,
  Where EGLGLnDynamicLibraryBundleInfo covers EGL + desktop GL.

- TODO: Tests w/ capable implementation

1 files changed, 10 insertions, 3 deletions

diff --git a/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java b/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
index 579dc27dc..98d1cea71 100644
--- a/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
+++ b/src/jogl/classes/jogamp/opengl/GLFBODrawableImpl.java
@@ -105,7 +105,7 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
 
     private final void setupFBO(final GL gl, final int idx, final int width, final int height, final int samples,
                                 final boolean useAlpha, final int depthBits, final int stencilBits,
-                                final boolean useTexture, final boolean realUnbind) {
+                                final boolean useTexture, final boolean setupViewportScissors, final boolean realUnbind) {
         final FBObject fbo = new FBObject();
         fbos[idx] = fbo;
 
@@ -156,6 +156,11 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
         // Also remedy for Bug 1020, i.e. OSX/Nvidia's FBO needs to be cleared before blitting,
         // otherwise first MSAA frame lacks antialiasing.
         fbo.bind(gl);
+        if( setupViewportScissors ) {
+            // Surfaceless: Set initial viewport/scissors
+            gl.glViewport(0, 0, width, height);
+            gl.glScissor(0, 0, width, height);
+        }
         if( useDepth ) {
             gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
         } else {
@@ -217,7 +222,9 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
 
             for(int i=0; i<fbosN; i++) {
                 setupFBO(gl, i, width, height, samples, useAlpha,
-                         chosenFBOCaps.getDepthBits(), chosenFBOCaps.getStencilBits(), useTexture, fbosN-1==i);
+                         chosenFBOCaps.getDepthBits(), chosenFBOCaps.getStencilBits(), useTexture,
+                         0==i && 0 == parent.getHandle() /* setupViewportScissors for surfaceless */,
+                         fbosN-1==i /* unbind */);
             }
             fbos[0].formatToGLCapabilities(chosenFBOCaps);
             chosenFBOCaps.setDoubleBuffered( chosenFBOCaps.getDoubleBuffered() || samples > 0 );
@@ -271,7 +278,7 @@ public class GLFBODrawableImpl extends GLDrawableImpl implements GLFBODrawable {
         // resetQuirk fallback
         fbos[idx].destroy(gl);
         final boolean useTexture = 0 != ( FBOMODE_USE_TEXTURE & fboModeBits );
-        setupFBO(gl, idx, width, height, samples, useAlpha, depthBits, stencilBits, useTexture, true);
+        setupFBO(gl, idx, width, height, samples, useAlpha, depthBits, stencilBits, useTexture, false, true);
     }
 
     private final void reset(final GL gl, int newSamples) throws GLException {