Bug 801: Introd. RenderState.BITHINT_GLOBAL_DEPTH_TEST_ENABLED hinting to deal w/ GL_DEPTH_TEST accordingly

Fixes VBORegion2PMSAAES2 no-depth-buffer usage
and allows user to control behavior w/o quering GL state.

If BITHINT_GLOBAL_DEPTH_TEST_ENABLED set:
  - RegionRenderer.defaultBlendEnable:  glDepthMask(false)
  - RegionRenderer.defaultBlendDisable: glDepthMask(true)
  - VBORegion2PMSAAES2 enables/disables GL_DEPTH_TEST, otherwise MSAA is corrupt.

2 files changed, 30 insertions, 5 deletions

diff --git a/src/jogl/classes/com/jogamp/graph/curve/opengl/RegionRenderer.java b/src/jogl/classes/com/jogamp/graph/curve/opengl/RegionRenderer.java
index a0a318a49..272099385 100644
--- a/src/jogl/classes/com/jogamp/graph/curve/opengl/RegionRenderer.java
+++ b/src/jogl/classes/com/jogamp/graph/curve/opengl/RegionRenderer.java
@@ -69,7 +69,8 @@ public class RegionRenderer {
 
     /**
      * Default {@link GL#GL_BLEND} <i>enable</i> {@link GLCallback},
-     * turning-off depth writing via {@link GL#glDepthMask(boolean)} and turning-on the {@link GL#GL_BLEND} state.
+     * turning-off depth writing via {@link GL#glDepthMask(boolean)} if {@link RenderState#BITHINT_GLOBAL_DEPTH_TEST_ENABLED} is set
+     * and turning-on the {@link GL#GL_BLEND} state.
      * <p>
      * Implementation also sets {@link RegionRenderer#getRenderState() RenderState}'s {@link RenderState#BITHINT_BLENDING_ENABLED blending bit-hint},
      * which will cause {@link GLRegion#draw(GL2ES2, RegionRenderer, int[]) GLRegion's draw-method}
@@ -82,7 +83,11 @@ public class RegionRenderer {
     public static final GLCallback defaultBlendEnable = new GLCallback() {
         @Override
         public void run(final GL gl, final RegionRenderer renderer) {
-            gl.glDepthMask(false);
+            if( renderer.rs.isHintMaskSet(RenderState.BITHINT_GLOBAL_DEPTH_TEST_ENABLED) ) {
+                gl.glDepthMask(false);
+                // gl.glDisable(GL.GL_DEPTH_TEST);
+                // gl.glDepthFunc(GL.GL_ALWAYS);
+            }
             gl.glEnable(GL.GL_BLEND);
             gl.glBlendEquation(GL.GL_FUNC_ADD); // default
             renderer.rs.setHintMask(RenderState.BITHINT_BLENDING_ENABLED);
@@ -92,7 +97,7 @@ public class RegionRenderer {
     /**
      * Default {@link GL#GL_BLEND} <i>disable</i> {@link GLCallback},
      * simply turning-off the {@link GL#GL_BLEND} state
-     * and turning-on depth writing via {@link GL#glDepthMask(boolean)}.
+     * and turning-on depth writing via {@link GL#glDepthMask(boolean)} if {@link RenderState#BITHINT_GLOBAL_DEPTH_TEST_ENABLED} is set.
      * <p>
      * Implementation also clears {@link RegionRenderer#getRenderState() RenderState}'s {@link RenderState#BITHINT_BLENDING_ENABLED blending bit-hint}.
      * </p>
@@ -104,7 +109,11 @@ public class RegionRenderer {
         public void run(final GL gl, final RegionRenderer renderer) {
             renderer.rs.clearHintMask(RenderState.BITHINT_BLENDING_ENABLED);
             gl.glDisable(GL.GL_BLEND);
-            gl.glDepthMask(true);
+            if( renderer.rs.isHintMaskSet(RenderState.BITHINT_GLOBAL_DEPTH_TEST_ENABLED) ) {
+                // gl.glEnable(GL.GL_DEPTH_TEST);
+                // gl.glDepthFunc(GL.GL_LESS);
+                gl.glDepthMask(true);
+            }
         }
     };
 
diff --git a/src/jogl/classes/com/jogamp/graph/curve/opengl/RenderState.java b/src/jogl/classes/com/jogamp/graph/curve/opengl/RenderState.java
index 7eb34a62d..f991855c0 100644
--- a/src/jogl/classes/com/jogamp/graph/curve/opengl/RenderState.java
+++ b/src/jogl/classes/com/jogamp/graph/curve/opengl/RenderState.java
@@ -58,12 +58,28 @@ public class RenderState {
      * and the clear-color to <i>transparent-black</i> in case of {@link Region#isTwoPass(int) multipass} FBO rendering.
      * </p>
      * <p>
-     * Shall be called by custom code, e.g. via {@link RegionRenderer}'s
+     * Shall be set by custom code, e.g. via {@link RegionRenderer}'s
      * enable and disable {@link RegionRenderer.GLCallback} as done in
      * {@link RegionRenderer#defaultBlendEnable} and {@link RegionRenderer#defaultBlendDisable}.
      * </p>
      */
     public static final int BITHINT_BLENDING_ENABLED = 1 << 0 ;
+    
+    /**
+     * Bitfield hint, {@link #isHintMaskSet(int) if set}
+     * stating globally <i>enabled</i> {@link GL#GL_DEPTH_TEST}, otherwise <i>disabled</i>.
+     * <p>
+     * Shall be set via {@link #setHintMask(int)} and cleared via {@link #clearHintMask(int)}.
+     * </p>
+     * <p>
+     * {@link GLRegion#draw(GL2ES2, RegionRenderer, int[]) GLRegion's draw-method}
+     * may toggle depth test, and reset it's state according to this hint.
+     * </p>
+     * <p>
+     * Shall be set by custom code, e.g. after {@link RenderState} or {@link RegionRenderer} construction.
+     * </p>
+     */
+    public static final int BITHINT_GLOBAL_DEPTH_TEST_ENABLED = 1 << 1 ;
 
     public static RenderState createRenderState(Vertex.Factory<? extends Vertex> pointFactory) {
         return new RenderState(pointFactory, null);