3 files changed, 63 insertions, 21 deletions

diff --git a/src/com/jogamp/opencl/CLMemory.java b/src/com/jogamp/opencl/CLMemory.java
index 7a3e82f7..f299439d 100644
--- a/src/com/jogamp/opencl/CLMemory.java
+++ b/src/com/jogamp/opencl/CLMemory.java
@@ -50,7 +50,7 @@ public abstract class CLMemory <B extends Buffer> extends CLObject implements CL
     
     B buffer;
     protected final int FLAGS;
-    protected final long size;
+    protected long size;
     
     // depends on the nio buffer type
     protected int elementSize;
@@ -65,11 +65,15 @@ public abstract class CLMemory <B extends Buffer> extends CLObject implements CL
         this.buffer = directBuffer;
         this.FLAGS = flags;
         this.size = size;
-        initElementSizes();
+        initElementSize();
+        initCLCapacity();
     }
 
-    private void initElementSizes() {
+    private void initElementSize() {
         this.elementSize = (buffer==null) ? 1 : Buffers.sizeOfBufferElem(buffer);
+    }
+
+    protected final void initCLCapacity() {
         this.clCapacity  = (int) (size / elementSize);
     }
 
@@ -118,7 +122,8 @@ public abstract class CLMemory <B extends Buffer> extends CLObject implements CL
                     +" but got " + buffer.getClass());
         }
         this.buffer = buffer;
-        initElementSizes();
+        initElementSize();
+        initCLCapacity();
         return this;
     }
 
diff --git a/src/com/jogamp/opencl/gl/CLGLBuffer.java b/src/com/jogamp/opencl/gl/CLGLBuffer.java
index 86fef680..148aa83d 100644
--- a/src/com/jogamp/opencl/gl/CLGLBuffer.java
+++ b/src/com/jogamp/opencl/gl/CLGLBuffer.java
@@ -28,9 +28,10 @@
 
 package com.jogamp.opencl.gl;
 
-import com.jogamp.opencl.CL;
 import com.jogamp.opencl.CLBuffer;
+import com.jogamp.opencl.CLCommandQueue;
 import com.jogamp.opencl.CLContext;
+import com.jogamp.opencl.CLException;
 
 import java.nio.Buffer;
 import javax.media.opengl.GLContext;
@@ -48,22 +49,22 @@ public final class CLGLBuffer<B extends Buffer> extends CLBuffer<B> implements C
      */
     public final int GLID;
 
-    private CLGLBuffer(CLContext context, B directBuffer, long id, int glObject, int flags) {
-        super(context, directBuffer, getSizeImpl(context.getCL(), id), id, flags);
+    private CLGLBuffer(CLContext context, B directBuffer, long id, int glObject, long size, int flags) {
+        super(context, directBuffer, size, id, flags);
         this.GLID = glObject;
     }
 
 
-    static <B extends Buffer> CLGLBuffer<B> create(CLContext context, B directBuffer, int flags, int glObject) {
+    static <B extends Buffer> CLGLBuffer<B> create(CLContext context, B directBuffer, long size, int flags, int glObject) {
         checkBuffer(directBuffer, flags);
         
-        CL cl = getCL(context);
-        int[] result = new int[1];
-        CLGLI clgli = (CLGLI)cl;
+        CLGLI clgli = (CLGLI)getCL(context);
         
+        int[] result = new int[1];
         long id = clgli.clCreateFromGLBuffer(context.ID, flags, glObject, result, 0);
+        CLException.checkForError(result[0], "can not create CLGLObject from #"+glObject);
 
-        return new CLGLBuffer<B>(context, directBuffer, id, glObject, flags);
+        return new CLGLBuffer<B>(context, directBuffer, id, glObject, size, flags);
     }
 
     static <B extends Buffer> void checkBuffer(B directBuffer, int flags) throws IllegalArgumentException {
@@ -75,6 +76,16 @@ public final class CLGLBuffer<B extends Buffer> extends CLBuffer<B> implements C
         }
     }
 
+    /**
+     * Updates the size of this CLGLBuffer by querying OpenGL.
+     * This method may only be called if this memory object has been acquired by calling
+     * {@link CLCommandQueue#putAcquireGLObject(com.jogamp.opencl.gl.CLGLObject)}.
+     */
+    public void updateSize() {
+        size = getSizeImpl(cl, ID);
+        initCLCapacity();
+    }
+
     public int getGLObjectID() {
         return GLID;
     }
@@ -94,7 +105,7 @@ public final class CLGLBuffer<B extends Buffer> extends CLBuffer<B> implements C
 
     @Override
     public <T extends Buffer> CLGLBuffer<T> cloneWith(T directBuffer) {
-        return new CLGLBuffer<T>(context, directBuffer, ID, GLID, FLAGS);
+        return new CLGLBuffer<T>(context, directBuffer, ID, GLID, size, FLAGS);
     }
 
     @Override
diff --git a/src/com/jogamp/opencl/gl/CLGLContext.java b/src/com/jogamp/opencl/gl/CLGLContext.java
index f8ca70af..6482f041 100644
--- a/src/com/jogamp/opencl/gl/CLGLContext.java
+++ b/src/com/jogamp/opencl/gl/CLGLContext.java
@@ -201,20 +201,46 @@ public final class CLGLContext extends CLContext {
     }
 
     // Buffers
-    public final CLGLBuffer<?> createFromGLBuffer(int glBuffer, Mem... flags) {
-        return createFromGLBuffer(null, glBuffer, Mem.flagsToInt(flags));
+    /**
+     * Creates a CLGLBuffer for memory sharing with the specified OpenGL buffer.
+     * @param glBuffer The OpenGL buffer handle like a vertex buffer or pixel buffer object.
+     * @param glBufferSize The size of the OpenGL buffer in bytes
+     * @param flags optional flags.
+     */
+    public final CLGLBuffer<?> createFromGLBuffer(int glBuffer, long glBufferSize, Mem... flags) {
+        return createFromGLBuffer(null, glBuffer, glBufferSize, Mem.flagsToInt(flags));
     }
 
-    public final CLGLBuffer<?> createFromGLBuffer(int glBuffer, int flags) {
-        return createFromGLBuffer(null, glBuffer, flags);
+    /**
+     * Creates a CLGLBuffer for memory sharing with the specified OpenGL buffer.
+     * @param glBuffer The OpenGL buffer handle like a vertex buffer or pixel buffer object.
+     * @param glBufferSize The size of the OpenGL buffer in bytes
+     * @param flags optional flags.
+     */
+    public final CLGLBuffer<?> createFromGLBuffer(int glBuffer, long glBufferSize, int flags) {
+        return createFromGLBuffer(null, glBuffer, glBufferSize, flags);
     }
 
-    public final <B extends Buffer> CLGLBuffer<B> createFromGLBuffer(B directBuffer, int glBuffer, Mem... flags) {
-        return createFromGLBuffer(directBuffer, glBuffer, Mem.flagsToInt(flags));
+    /**
+     * Creates a CLGLBuffer for memory sharing with the specified OpenGL buffer.
+     * @param directBuffer A direct allocated NIO buffer for data transfers between java and OpenCL.
+     * @param glBuffer The OpenGL buffer handle like a vertex buffer or pixel buffer object.
+     * @param glBufferSize The size of the OpenGL buffer in bytes
+     * @param flags optional flags.
+     */
+    public final <B extends Buffer> CLGLBuffer<B> createFromGLBuffer(B directBuffer, int glBuffer, long glBufferSize, Mem... flags) {
+        return createFromGLBuffer(directBuffer, glBuffer, glBufferSize, Mem.flagsToInt(flags));
     }
 
-    public final <B extends Buffer> CLGLBuffer<B> createFromGLBuffer(B directBuffer, int glBuffer, int flags) {
-        CLGLBuffer<B> buffer = CLGLBuffer.create(this, directBuffer, flags, glBuffer);
+    /**
+     * Creates a CLGLBuffer for memory sharing with the specified OpenGL buffer.
+     * @param directBuffer A direct allocated NIO buffer for data transfers between java and OpenCL.
+     * @param glBuffer The OpenGL buffer handle like a vertex buffer or pixel buffer object.
+     * @param glBufferSize The size of the OpenGL buffer in bytes
+     * @param flags optional flags.
+     */
+    public final <B extends Buffer> CLGLBuffer<B> createFromGLBuffer(B directBuffer, int glBuffer, long glBufferSize, int flags) {
+        CLGLBuffer<B> buffer = CLGLBuffer.create(this, directBuffer, glBufferSize, flags, glBuffer);
         memoryObjects.add(buffer);
         return buffer;
     }