1 files changed, 107 insertions, 0 deletions
diff --git a/src/demo/ReadBufferUtil.java b/src/demo/ReadBufferUtil.java
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+/**
+ * Copyright 2010 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 demo;
+
+import com.jogamp.opengl.util.GLBuffers;
+import java.nio.*;
+import javax.media.opengl.*;
+
+import com.jogamp.opengl.util.texture.Texture;
+import com.jogamp.opengl.util.texture.TextureData;
+
+public class ReadBufferUtil {
+    protected int readPixelSizeLast = 0;
+    protected Buffer readPixelBuffer = null;
+    protected TextureData readTextureData = null;
+    protected Texture readTexture = new Texture(GL.GL_TEXTURE_2D);
+
+    public Buffer getPixelBuffer() { return readPixelBuffer; }
+    public void rewindPixelBuffer() { readPixelBuffer.rewind(); }
+
+    public TextureData getTextureData() { return readTextureData; }
+    public Texture getTexture() { return readTexture; }
+
+    public boolean isValid() {
+      return null!=readTexture && null!=readTextureData && null!=readPixelBuffer ;
+    }
+
+    public void fetchOffscreenTexture(GLDrawable drawable, GL gl) {
+        int readPixelSize = drawable.getWidth() * drawable.getHeight() * 3 ; // RGB
+        boolean newData = false;
+        if(readPixelSize>readPixelSizeLast) {
+            readPixelBuffer = GLBuffers.newDirectGLBuffer(GL.GL_UNSIGNED_BYTE, readPixelSize);
+            readPixelSizeLast = readPixelSize ;
+            try {
+                readTextureData = new TextureData(
+                           gl.getGLProfile(),
+                           // gl.isGL2GL3()?gl.GL_RGBA:gl.GL_RGB,
+                           GL.GL_RGB,
+                           drawable.getWidth(), drawable.getHeight(),
+                           0, 
+                           GL.GL_RGB,
+                           GL.GL_UNSIGNED_BYTE,
+                           false, false, 
+                           false /* flip */,
+                           readPixelBuffer,
+                           null /* Flusher */);
+                newData = true;
+            } catch (Exception e) {
+                readTextureData = null;
+                readPixelBuffer = null;
+                readPixelSizeLast = 0;
+                throw new RuntimeException("can not fetch offscreen texture", e);
+            }
+        }
+        if(null!=readPixelBuffer) {
+            readPixelBuffer.clear();
+            gl.glReadPixels(0, 0, drawable.getWidth(), drawable.getHeight(), GL.GL_RGB, GL.GL_UNSIGNED_BYTE, readPixelBuffer);
+            readPixelBuffer.rewind();
+            if(newData) {
+                readTexture.updateImage(readTextureData);
+            } else {
+                readTexture.updateSubImage(readTextureData, 0, 
+                                           0, 0, // src offset
+                                           0, 0, // dst offset
+                                           drawable.getWidth(), drawable.getHeight());
+            }
+            readPixelBuffer.rewind();
+        }
+    }
+
+    @SuppressWarnings("deprecation")
+    public void dispose() {
+        readTexture.dispose();
+        readTextureData = null;
+        readPixelBuffer.clear();
+        readPixelBuffer = null;
+        readPixelSizeLast = 0;
+    }
+
+}
+