JOGL/NEWT: Animator fixes

Consider use cases with many drawables and no drawables at start,
this had to be reflected all over this patch set, implementation,
usage and test cases.

- GLAnimatorControl
  - refine API doc / states
  - add 'void remove(GLAutoDrawable drawable);'

- Animator*:

  - using RecursiveLock 'stateSync' for all actions out of the big synchronized (animator) block:

     - get status methods (thread, isPaused, ..), hence no more synchronized

     - display drawables change, utilizing synced ArrayList swap

    This removes the need for volatiles usage shouldPause/shouldStop within the display method.

  - added blocking wait for state change for add(GLAutoDrawable)/remove(GLAutoDrawable) method

  - remove flawed double checked locking in anim thread (pause/idle condition)

  - thread is now a daemon thread, hence it won't hinder the JVM from shutdown

  -

- Animator use change:

  - Always resume after pause, except in case of final destroy -> NEWT invalidate / GLCanvas,
    this considers use cases with many drawables and no drawables at start.

  - GLDrawableHelper: Don't pause at implicit dispose()

4 files changed, 29 insertions, 11 deletions

diff --git a/src/jogl/classes/javax/media/opengl/GLAnimatorControl.java b/src/jogl/classes/javax/media/opengl/GLAnimatorControl.java
index 01e5646f9..98d7bc48b 100644
--- a/src/jogl/classes/javax/media/opengl/GLAnimatorControl.java
+++ b/src/jogl/classes/javax/media/opengl/GLAnimatorControl.java
@@ -79,7 +79,7 @@ public interface GLAnimatorControl {
     public void resetCounter();
 
     /**
-     * Indicates whether this animator is currently running, ie started.
+     * Indicates whether this animator is running, ie. has been started and not stopped.
      *
      * @see #start()
      * @see #stop()
@@ -89,7 +89,8 @@ public interface GLAnimatorControl {
     boolean isStarted();
 
     /**
-     * Indicates whether this animator is currently running and not paused.
+     * Indicates whether this animator is running and animating,<br>
+     * the latter is true if it has {@link GLAutoDrawable}s to render and is not paused.
      *
      * @see #start()
      * @see #stop()
@@ -99,7 +100,7 @@ public interface GLAnimatorControl {
     boolean isAnimating();
 
     /**
-     * Indicates whether this animator is currently running and paused.
+     * Indicates whether this animator is running and paused.
      *
      * @see #start()
      * @see #stop()
@@ -109,7 +110,7 @@ public interface GLAnimatorControl {
     boolean isPaused();
 
     /**
-     * @return The animation thread if started, ie running.
+     * @return The animation thread if running, otherwise null.
      *
      * @see #start()
      * @see #stop()
@@ -158,7 +159,7 @@ public interface GLAnimatorControl {
      *
      * @see #resume()
      * @see #isAnimating()
-     * @throws GLException if not started or not animating or already paused
+     * @throws GLException if not started or already paused
      */
     void pause();
 
@@ -177,4 +178,15 @@ public interface GLAnimatorControl {
      * @throws GLException if not started or not paused
      */
     void resume();
+
+    /**
+     * Removes a drawable from the animator's list of rendering drawables.<br>
+     * This method should get called in case a drawable becomes invalid,
+     * and will not be recovered.<br>
+     * This allows the animator thread to become idle in case the last drawable
+     * has reached it's end of life.<br>
+     * 
+     * @param drawable the to be removed drawable
+     */
+    void remove(GLAutoDrawable drawable);
 }
diff --git a/src/jogl/classes/javax/media/opengl/GLAutoDrawable.java b/src/jogl/classes/javax/media/opengl/GLAutoDrawable.java
index 12ded8736..cde327a07 100644
--- a/src/jogl/classes/javax/media/opengl/GLAutoDrawable.java
+++ b/src/jogl/classes/javax/media/opengl/GLAutoDrawable.java
@@ -40,7 +40,6 @@
 
 package javax.media.opengl;
 
-import javax.media.opengl.glu.*;
 import com.jogamp.opengl.impl.Debug;
 import java.security.*;
 
diff --git a/src/jogl/classes/javax/media/opengl/GLCapabilities.java b/src/jogl/classes/javax/media/opengl/GLCapabilities.java
index 3d2e2bcc9..82f83dc82 100644
--- a/src/jogl/classes/javax/media/opengl/GLCapabilities.java
+++ b/src/jogl/classes/javax/media/opengl/GLCapabilities.java
@@ -59,7 +59,7 @@ public class GLCapabilities extends Capabilities implements Cloneable, GLCapabil
   private boolean doubleBuffered = true;
   private boolean stereo         = false;
   private boolean hardwareAccelerated = true;
-  private int     depthBits      = 24;
+  private int     depthBits      = 16;
   private int     stencilBits    = 0;
   private int     accumRedBits   = 0;
   private int     accumGreenBits = 0;
diff --git a/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java b/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java
index f2016a23c..265c7ff49 100644
--- a/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java
+++ b/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java
@@ -347,10 +347,17 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable {
     }
 
     if(null!=context) {
-        boolean animatorWasAnimating = false;
+        boolean animatorPaused = false;
         GLAnimatorControl animator =  getAnimator();
         if(null!=animator) {
-            animatorWasAnimating = animator.isAnimating();
+            if(regenerate) {
+                if(animator.isStarted() && !animator.isPaused()) {
+                    animator.pause();
+                    animatorPaused = true;
+                }
+            } else {
+                animator.remove(this);
+            }
         }
 
         disposeRegenerate=regenerate;
@@ -376,8 +383,8 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable {
           drawableHelper.invokeGL(drawable, context, disposeAction, null);
         }
 
-        if(regenerate && animatorWasAnimating && animator.isPaused()) {
-          animator.resume();
+        if(animatorPaused) {
+            animator.resume();
         }
     }
     if(!regenerate) {