Fix Bug 826: GLJPanel: Fully restore TextureState and Viewport

In FBO mode save TextureState of current texture-unit,
as well as for the fbo texture-unit if the latter is a different.

In glslTextureRaster mode for verical flip (using FBO),
set the viewport to drawable size if before flipping and restore afterward - if equired.

TestGLJPanelTextureStateAWT fully tests use cases:
  - Keep texture bound w/ same or other texture-unit
  - Use 2 viewports within one drawable and keep it

2 files changed, 213 insertions, 7 deletions

diff --git a/src/jogl/classes/com/jogamp/opengl/util/texture/TextureState.java b/src/jogl/classes/com/jogamp/opengl/util/texture/TextureState.java
new file mode 100644
index 000000000..4a5d368e3
--- /dev/null
+++ b/src/jogl/classes/com/jogamp/opengl/util/texture/TextureState.java
@@ -0,0 +1,167 @@
+/**
+ * Copyright 2013 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ *
+ *    1. Redistributions of source code must retain the above copyright notice, this list of
+ *       conditions and the following disclaimer.
+ *
+ *    2. Redistributions in binary form must reproduce the above copyright notice, this list
+ *       of conditions and the following disclaimer in the documentation and/or other materials
+ *       provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
+package com.jogamp.opengl.util.texture;
+
+import javax.media.opengl.GL;
+import javax.media.opengl.GL2ES2;
+import javax.media.opengl.GL2GL3;
+import javax.media.opengl.GL3;
+import javax.media.opengl.GLException;
+
+/**
+ * Preserves a [ texture-unit, texture-target ] state.
+ * <p>
+ * The states keys are the retrieved active texture-unit and the given texture-target
+ * for which the following states are being queried:
+ * <pre>
+ *   - texture-object
+ *   - GL.GL_TEXTURE_MAG_FILTER
+ *   - GL.GL_TEXTURE_MIN_FILTER
+ *   - GL.GL_TEXTURE_WRAP_S
+ *   - GL.GL_TEXTURE_WRAP_T            
+ * </pre>
+ */
+public class TextureState {
+    /** 
+     * Returns the <code>pname</code> to query the <code>textureTarget</code> currently bound to the active texture-unit.
+     * <p>
+     * Returns <code>0</code> is <code>textureTarget</code> is not supported.
+     * </p> 
+     */ 
+    public static final int getTextureTargetQueryName(int textureTarget) {
+        final int texBindQName;
+        switch(textureTarget) {
+            case GL.GL_TEXTURE_2D: texBindQName = GL.GL_TEXTURE_BINDING_2D; break; 
+            case GL.GL_TEXTURE_CUBE_MAP: texBindQName = GL.GL_TEXTURE_BINDING_CUBE_MAP; break; 
+            case GL2ES2.GL_TEXTURE_3D: texBindQName = GL2ES2.GL_TEXTURE_BINDING_3D; break; 
+            case GL2GL3.GL_TEXTURE_1D: texBindQName = GL2GL3.GL_TEXTURE_BINDING_1D; break; 
+            case GL2GL3.GL_TEXTURE_1D_ARRAY: texBindQName = GL2GL3.GL_TEXTURE_BINDING_1D_ARRAY; break; 
+            case GL2GL3.GL_TEXTURE_2D_ARRAY: texBindQName = GL2GL3.GL_TEXTURE_BINDING_2D_ARRAY; break; 
+            case GL2GL3.GL_TEXTURE_RECTANGLE: texBindQName = GL2GL3.GL_TEXTURE_BINDING_RECTANGLE; break; 
+            case GL2GL3.GL_TEXTURE_BUFFER: texBindQName = GL2GL3.GL_TEXTURE_BINDING_BUFFER; break; 
+            case GL3.GL_TEXTURE_2D_MULTISAMPLE: texBindQName = GL3.GL_TEXTURE_BINDING_2D_MULTISAMPLE; break; 
+            case GL3.GL_TEXTURE_2D_MULTISAMPLE_ARRAY: texBindQName = GL3.GL_TEXTURE_BINDING_2D_MULTISAMPLE_ARRAY; break;
+            default: texBindQName = 0;
+        }
+        return texBindQName;
+    }
+    
+    private final int target;
+    /** 
+     * <pre>
+     *   0 - unit
+     *   1 - texture object
+     *   2 - GL.GL_TEXTURE_MAG_FILTER
+     *   3 - GL.GL_TEXTURE_MIN_FILTER
+     *   4 - GL.GL_TEXTURE_WRAP_S
+     *   5 - GL.GL_TEXTURE_WRAP_T            
+     * </pre>
+     */
+    private final int[] state = new int[] { 0, 0, 0, 0, 0, 0 };
+    
+    private static final String toHexString(int i) { return "0x"+Integer.toHexString(i); }
+    
+    private static final int activeTexture(GL gl) {
+        final int[] vi = { 0 };
+        gl.glGetIntegerv(GL.GL_ACTIVE_TEXTURE, vi, 0);
+        return vi[0];
+    }
+    
+    /**
+     * Creates a texture state for the retrieved active texture-unit and the given texture-target.
+     * See {@link TextureState}.
+     * @param gl current GL context's GL object
+     * @param textureTarget
+     * @throws GLException if textureTarget is not supported
+     */
+    public TextureState(GL gl, int textureTarget) throws GLException {
+        this(gl, activeTexture(gl), textureTarget);
+    }
+    
+    /**
+     * Creates a texture state for the given active texture-unit and the given texture-target.
+     * See {@link TextureState}.
+     * @param gl current GL context's GL object
+     * @param textureUnit  of range [ {@link GL#GL_TEXTURE0}.. ]
+     * @param textureTarget
+     * @throws GLException if textureTarget is not supported
+     */
+    public TextureState(GL gl, int textureUnit, int textureTarget) throws GLException {
+        target = textureTarget;
+        state[0] = textureUnit;
+        final int texBindQName = getTextureTargetQueryName(textureTarget);
+        if( 0 == texBindQName ) {
+            throw new GLException("Unsupported textureTarget "+toHexString(textureTarget));
+        }
+        gl.glGetIntegerv(texBindQName, state, 1);
+        gl.glGetTexParameteriv(target, GL.GL_TEXTURE_MAG_FILTER, state, 2);
+        gl.glGetTexParameteriv(target, GL.GL_TEXTURE_MIN_FILTER, state, 3);
+        gl.glGetTexParameteriv(target, GL.GL_TEXTURE_WRAP_S, state, 4);
+        gl.glGetTexParameteriv(target, GL.GL_TEXTURE_WRAP_T, state, 5);
+    }
+    
+    /**
+     * Restores the texture-unit's texture-target state.
+     * <p>
+     * First the texture-unit is activated, then all states are restored.
+     * </p>
+     * @param gl current GL context's GL object
+     */
+    public final void restore(GL gl) {
+        gl.glActiveTexture(state[0]);
+        gl.glBindTexture(target, state[1]);
+        gl.glTexParameteri(target, GL.GL_TEXTURE_MAG_FILTER, state[2]);
+        gl.glTexParameteri(target, GL.GL_TEXTURE_MIN_FILTER, state[3]);
+        gl.glTexParameteri(target, GL.GL_TEXTURE_WRAP_S, state[4]);
+        gl.glTexParameteri(target, GL.GL_TEXTURE_WRAP_T, state[5]);
+    }
+    
+    /** Returns the texture-unit of this state, key value. Unit is of range [ {@link GL#GL_TEXTURE0}.. ]. */
+    public final int getUnit() { return state[0]; }
+    /** Returns the texture-target of this state, key value. */
+    public final int getTarget() { return target; }
+    
+    /** Returns the state's texture-object. */
+    public final int getObject() { return state[1]; }
+    /** Returns the state's mag-filter param. */
+    public final int getMagFilter() { return state[2]; }
+    /** Returns the state's min-filter param. */
+    public final int getMinFilter() { return state[3]; }
+    /** Returns the state's wrap-s param. */
+    public final int getWrapS() { return state[4]; }
+    /** Returns the state's wrap-t param. */
+    public final int getWrapT() { return state[5]; }
+    
+    
+    public final String toString() {
+        return "TextureState[unit "+(state[0] - GL.GL_TEXTURE0)+", target "+toHexString(target)+
+                ": obj "+toHexString(state[1])+
+                ", filter[mag "+toHexString(state[2])+", min "+toHexString(state[3])+"], "+ 
+                ": wrap[s "+toHexString(state[4])+", t "+toHexString(state[5])+"]]";
+    }
+}
diff --git a/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java b/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java
index e9d1b38d2..61ff4997e 100644
--- a/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java
+++ b/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java
@@ -101,6 +101,7 @@ import com.jogamp.opengl.util.TileRenderer;
 import com.jogamp.opengl.util.awt.AWTGLPixelBuffer;
 import com.jogamp.opengl.util.awt.AWTGLPixelBuffer.AWTGLPixelBufferProvider;
 import com.jogamp.opengl.util.awt.AWTGLPixelBuffer.SingleAWTGLPixelBufferProvider;
+import com.jogamp.opengl.util.texture.TextureState;
 
 /** A lightweight Swing component which provides OpenGL rendering
     support. Provided for compatibility with Swing user interfaces
@@ -1219,6 +1220,7 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
 
     // Implementation using software rendering
     private GLDrawableImpl offscreenDrawable;
+    private boolean offscreenIsFBO;
     private FBObject fboFlipped;
     private GLSLTextureRaster glslTextureRaster;
     
@@ -1264,7 +1266,8 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
               final GL gl = offscreenContext.getGL();
               flipVertical = offscreenDrawable.isGLOriented();
               final GLCapabilitiesImmutable chosenCaps = offscreenDrawable.getChosenGLCapabilities();
-              if( USE_GLSL_TEXTURE_RASTERIZER && chosenCaps.isFBO() && flipVertical && gl.isGL2ES2() ) {
+              offscreenIsFBO = chosenCaps.isFBO();
+              if( USE_GLSL_TEXTURE_RASTERIZER && offscreenIsFBO && flipVertical && gl.isGL2ES2() ) {
                   final boolean _autoSwapBufferMode = helper.getAutoSwapBufferMode();
                   helper.setAutoSwapBufferMode(false);
                   final GLFBODrawable fboDrawable = (GLFBODrawable) offscreenDrawable;
@@ -1344,6 +1347,7 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
             adevice.close();
         }
       }
+      offscreenIsFBO = false;
       
       if( null != readBackIntsForCPUVFlip ) { 
           readBackIntsForCPUVFlip.clear();
@@ -1420,10 +1424,23 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
            readBackInts = readBackIntsForCPUVFlip;
         }
 
-        if( DEBUG_VIEWPORT ) {
-            int[] vp = new int[] { 0, 0, 0, 0 };
-            gl.glGetIntegerv(GL.GL_VIEWPORT, vp, 0);
-            System.err.println(getThreadName()+": GLJPanel.OffscreenBackend.postGL: Viewport: "+vp[0]+"/"+vp[1]+" "+vp[2]+"x"+vp[3]);
+        final TextureState usrTexState, fboTexState;
+        final int fboTexUnit = GL.GL_TEXTURE0 + ( offscreenIsFBO ? ((GLFBODrawable)offscreenDrawable).getTextureUnit() : 0 );
+        
+        if( offscreenIsFBO ) {
+            usrTexState = new TextureState(gl, GL.GL_TEXTURE_2D);
+            if( fboTexUnit != usrTexState.getUnit() ) {
+                // glActiveTexture(..) + glBindTexture(..) are implicit performed in GLFBODrawableImpl's
+                // swapBuffers/contextMadeCurent -> swapFBOImpl.
+                // We need to cache the texture unit's bound texture-id before it's overwritten.
+                gl.glActiveTexture(fboTexUnit);
+                fboTexState = new TextureState(gl, fboTexUnit, GL.GL_TEXTURE_2D);
+            } else {
+                fboTexState = usrTexState;
+            }
+        } else {
+            usrTexState = null;
+            fboTexState = null;
         }
         
         // Must now copy pixels from offscreen context into surface
@@ -1439,6 +1456,20 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
         offscreenDrawable.swapBuffers();
         
         if(null != glslTextureRaster) { // implies flippedVertical
+            final boolean viewportChange;
+            final int[] usrViewport = new int[] { 0, 0, 0, 0 };
+            gl.glGetIntegerv(GL.GL_VIEWPORT, usrViewport, 0);
+            viewportChange = 0 != usrViewport[0] || 0 != usrViewport[1] || 
+                             offscreenDrawable.getWidth() != usrViewport[2] || offscreenDrawable.getHeight() != usrViewport[3];
+            if( DEBUG_VIEWPORT ) {
+                System.err.println(getThreadName()+": GLJPanel.OffscreenBackend.postGL: Viewport: change "+viewportChange+
+                         ", "+usrViewport[0]+"/"+usrViewport[1]+" "+usrViewport[2]+"x"+usrViewport[3]+
+                         " -> 0/0 "+offscreenDrawable.getWidth()+"x"+offscreenDrawable.getHeight());
+            }
+            if( viewportChange ) {
+                gl.glViewport(0, 0, offscreenDrawable.getWidth(), offscreenDrawable.getHeight());
+            }            
+                        
             // perform vert-flipping via OpenGL/FBO        
             final GLFBODrawable fboDrawable = (GLFBODrawable)offscreenDrawable;
             final FBObject.TextureAttachment fboTex = fboDrawable.getTextureBuffer(GL.GL_FRONT);
@@ -1446,12 +1477,17 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
             fboFlipped.bind(gl);
             
             // gl.glActiveTexture(GL.GL_TEXTURE0 + fboDrawable.getTextureUnit()); // implicit by GLFBODrawableImpl: swapBuffers/contextMadeCurent -> swapFBOImpl
-            gl.glBindTexture(GL.GL_TEXTURE_2D, fboTex.getName());
+            gl.glBindTexture(GL.GL_TEXTURE_2D, fboTex.getName());            
             // gl.glClear(GL.GL_DEPTH_BUFFER_BIT); // fboFlipped runs w/o DEPTH!
+            
             glslTextureRaster.display(gl.getGL2ES2());
             gl.glReadPixels(0, 0, panelWidth, panelHeight, pixelAttribs.format, pixelAttribs.type, readBackInts);
-
+            
             fboFlipped.unbind(gl);
+            if( viewportChange ) {
+                gl.glViewport(usrViewport[0], usrViewport[1], usrViewport[2], usrViewport[3]);
+            }
+            fboTexState.restore(gl);
         } else {
             gl.glReadPixels(0, 0, panelWidth, panelHeight, pixelAttribs.format, pixelAttribs.type, readBackInts);
             
@@ -1471,6 +1507,9 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
                 }
             }
         }
+        if( offscreenIsFBO && fboTexUnit != usrTexState.getUnit() ) {
+            usrTexState.restore(gl);
+        }
 
         // Restore saved modes.
         psm.restore(gl);