Add GLStateKeeper handling GLEventListenerState preservation and restauration for GLAutoDrawable

- New GLStateKeeper interface, package com.jogamp.opengl

  Implemented by:
    - GLAutoDrawableBase

  Currently supported by:
    - NEWT GLWindow

- GLEventListenerState package move:
   com.jogamp.opengl.util ->  com.jogamp.opengl

1 files changed, 87 insertions, 0 deletions

diff --git a/src/jogl/classes/com/jogamp/opengl/GLStateKeeper.java b/src/jogl/classes/com/jogamp/opengl/GLStateKeeper.java
new file mode 100644
index 000000000..410907bee
--- /dev/null
+++ b/src/jogl/classes/com/jogamp/opengl/GLStateKeeper.java
@@ -0,0 +1,87 @@
+/**
+ * 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;
+
+/**
+ * Interface adding a {@link GLEventListenerState} protocol to {@link GLAutoDrawable}s
+ * or other self-contained compound types combining {@link GLDrawable}, {@link GLContext} and {@link GLEventListener}.
+ * <p>
+ * Implementing classes {@link #isGLStatePreservationSupported() may support} preservation 
+ * of the {@link GLContext} state and it's associated {@link GLEventListener}. 
+ * </p> 
+ */
+public interface GLStateKeeper {
+    
+    /** Listener for preserve and restore notifications. */
+    public static interface Listener {
+        /** Invoked before preservation. */
+        void glStatePreserveNotify(GLStateKeeper glsk);
+        /** Invoked after restoration. */
+        void glStateRestored(GLStateKeeper glsk);
+    }
+    
+    /** 
+     * Sets a {@link Listener}, overriding the old one.
+     * @param l the new {@link Listener}.
+     * @return the previous {@link Listener}.
+     */
+    public Listener setGLStateKeeperListener(Listener l);
+    
+    /**
+     * @return <code>true</code> if GL state preservation is supported in implementation and on current platform, <code>false</code> otherwise.
+     * @see #preserveGLStateAtDestroy(boolean)
+     * @see #getPreservedGLState()
+     */
+    public boolean isGLStatePreservationSupported();
+    
+    /**
+     * If set to <code>true</code>, the next {@link GLAutoDrawable#destroy()} operation will
+     * {@link #pullGLEventListenerState() pull} to preserve the {@link GLEventListenerState}.
+     * <p>
+     * This is a one-shot flag, i.e. after preserving the {@link GLEventListenerState},
+     * the flag is cleared.
+     * </p>
+     * <p>
+     * A preserved {@link GLEventListenerState} will be {@link #pushGLEventListenerState() pushed} 
+     * if realized again. 
+     * </p>
+     * @return <code>true</code> if supported and successful, <code>false</code> otherwise.
+     * @see #isGLStatePreservationSupported()
+     * @see #getPreservedGLState()
+     */
+    public boolean preserveGLStateAtDestroy(boolean value);
+    
+    /**
+     * Returns the preserved {@link GLEventListenerState} if preservation was performed,
+     * otherwise <code>null</code>. 
+     * @see #isGLStatePreservationSupported()
+     * @see #preserveGLStateAtDestroy(boolean)
+     */
+    public GLEventListenerState getPreservedGLState();
+
+}