4 files changed, 39 insertions, 5 deletions
diff --git a/src/net/java/games/jogl/GLDrawable.java b/src/net/java/games/jogl/GLDrawable.java
index 7c671c0b2..7c120f7af 100644
--- a/src/net/java/games/jogl/GLDrawable.java
+++ b/src/net/java/games/jogl/GLDrawable.java
@@ -94,10 +94,22 @@ public interface GLDrawable extends ComponentEvents {
       Dimension is null a new one will be allocated and returned. */
   public Dimension getSize(Dimension d);
 
-  /** Returns the {@link GL} pipeline object this GLDrawable uses. */
+  /** Returns the {@link GL} pipeline object this GLDrawable uses.  If
+      this method is called outside of the {@link GLEventListener}'s
+      callback methods (init, display, etc.) it may return null. Users
+      should not rely on the identity of the returned GL object; for
+      example, users should not maintain a hash table with the GL
+      object as the key. Additionally, the GL object should not be
+      cached in client code, but should be re-fetched from the
+      GLDrawable at the beginning of each call to init, display,
+      etc. */
   public GL getGL();
 
-  /** Sets the {@link GL} pipeline object this GLDrawable uses. */
+  /** Sets the {@link GL} pipeline object this GLDrawable uses. This
+      should only be called from within the GLEventListener's callback
+      methods, and usually only from within the init() method, in
+      order to install a composable pipeline. See the JOGL demos for
+      examples. */
   public void setGL(GL gl);
 
   /** Returns the {@link GLU} pipeline object this GLDrawable uses. */
diff --git a/src/net/java/games/jogl/GLJPanel.java b/src/net/java/games/jogl/GLJPanel.java
index d21081dfe..bf102710b 100644
--- a/src/net/java/games/jogl/GLJPanel.java
+++ b/src/net/java/games/jogl/GLJPanel.java
@@ -291,17 +291,27 @@ public final class GLJPanel extends JPanel implements GLDrawable {
 
   public GL getGL() {
     if (!hardwareAccelerationDisabled) {
+      if (pbuffer == null) {
+        return null;
+      }
       return pbuffer.getGL();
     } else {
+      if (offscreenContext == null) {
+        return null;
+      }
       return offscreenContext.getGL();
     }
   }
 
   public void setGL(GL gl) {
     if (!hardwareAccelerationDisabled) {
-      pbuffer.setGL(gl);
+      if (pbuffer != null) {
+        pbuffer.setGL(gl);
+      }
     } else {
-      offscreenContext.setGL(gl);
+      if (offscreenContext != null) {
+        offscreenContext.setGL(gl);
+      }
     }
   }
 
@@ -473,6 +483,9 @@ public final class GLJPanel extends JPanel implements GLDrawable {
 
     public void init(GLDrawable drawable) {
       if (!hardwareAccelerationDisabled) {
+        if (DEBUG) {
+          System.err.println("GLJPanel$Updater.init(): pbufferInitializationCompleted = true");
+        }
         pbufferInitializationCompleted = true;
         EventQueue.invokeLater(new Runnable() {
             public void run() {
diff --git a/src/net/java/games/jogl/impl/GLContext.java b/src/net/java/games/jogl/impl/GLContext.java
index 318ff24a2..e2f591278 100644
--- a/src/net/java/games/jogl/impl/GLContext.java
+++ b/src/net/java/games/jogl/impl/GLContext.java
@@ -484,6 +484,12 @@ public abstract class GLContext {
    * the definition of "available".
    */
   protected void resetGLFunctionAvailability() {
+    // In order to be able to allow the user to uniformly install the
+    // debug and trace pipelines in their GLEventListener.init()
+    // method (for both GLCanvas and GLJPanel), we need to reset the
+    // actual GL object in the GLDrawable as well
+    setGL(createGL());
+
     functionAvailability.flush();
     if (!haveResetGLUProcAddressTable) {
       if (DEBUG) {
diff --git a/src/net/java/games/jogl/impl/windows/WindowsPbufferGLContext.java b/src/net/java/games/jogl/impl/windows/WindowsPbufferGLContext.java
index f0ce74d9d..b0a164f26 100644
--- a/src/net/java/games/jogl/impl/windows/WindowsPbufferGLContext.java
+++ b/src/net/java/games/jogl/impl/windows/WindowsPbufferGLContext.java
@@ -432,7 +432,10 @@ public class WindowsPbufferGLContext extends WindowsGLContext {
     if (hglrc != 0) {
       super.destroyImpl();
       // Must release DC and pbuffer
-      GL gl = getGL();
+      // NOTE that since the context is not current, glGetError() can
+      // not be called here, so we skip the use of any composable
+      // pipelines
+      GL gl = createGL();
       if (gl.wglReleasePbufferDCARB(buffer, hdc) == 0) {
         throw new GLException("Error releasing pbuffer device context: error code " + WGL.GetLastError());
       }