One can now call readFrameBuffer with a specific format, implementation has been done for the GLRenderer only.

For now only placeholders have been done for the renderers that are still not using URA (all except LWJGL).

jme3-android/src/main/java/com/jme3/renderer/android/OGLESShaderRenderer.java

@@ -2564,4 +2564,8 @@ public class OGLESShaderRenderer implements Renderer {
     public void setLinearizeSrgbImages(boolean linearize) {
         //TODO once opglES3.0 is supported maybe....
     }
+    
+    public void readFrameBufferWithFormat(FrameBuffer fb, ByteBuffer byteBuf, Image.Format format) {
+        throw new UnsupportedOperationException("Not supported yet. URA will make that work seamlessly"); 
+    }
 }

jme3-core/src/main/java/com/jme3/renderer/Renderer.java

@@ -222,7 +222,7 @@ public interface Renderer {
     /**
      * Reads the pixels currently stored in the specified framebuffer
      * into the given ByteBuffer object. 
-     * Only color pixels are transferred, the format is BGRA with 8 bits 
+     * Only color pixels are transferred, the format is RGBA with 8 bits 
      * per component. The given byte buffer should have at least
      * fb.getWidth() * fb.getHeight() * 4 bytes remaining.
      * 
@@ -231,6 +231,19 @@ public interface Renderer {
      */
     public void readFrameBuffer(FrameBuffer fb, ByteBuffer byteBuf);
     
+    /**
+     * Reads the pixels currently stored in the specified framebuffer
+     * into the given ByteBuffer object. 
+     * Only color pixels are transferred, witht hte given format. 
+     * The given byte buffer should have at least
+     * fb.getWidth() * fb.getHeight() * 4 bytes remaining.
+     * 
+     * @param fb The framebuffer to read from
+     * @param byteBuf The bytebuffer to transfer color data to
+     * @param format the image format to use when reading the frameBuffer.
+     */
+    public void readFrameBufferWithFormat(FrameBuffer fb, ByteBuffer byteBuf, Image.Format format);
+
     /**
      * Deletes a framebuffer and all attached renderbuffers
      */

jme3-core/src/main/java/com/jme3/renderer/opengl/GLRenderer.java

@@ -1629,6 +1629,10 @@ public class GLRenderer implements Renderer {
     }
 
     public void readFrameBuffer(FrameBuffer fb, ByteBuffer byteBuf) {
+        readFrameBufferWithGLFormat(fb, byteBuf, GL.GL_RGBA, GL.GL_UNSIGNED_BYTE);
+    }
+    
+    private void readFrameBufferWithGLFormat(FrameBuffer fb, ByteBuffer byteBuf, int glFormat, int dataType) {
         if (fb != null) {
             RenderBuffer rb = fb.getColorBuffer();
             if (rb == null) {
@@ -1647,7 +1651,12 @@ public class GLRenderer implements Renderer {
             setFrameBuffer(null);
         }
 
-        gl.glReadPixels(vpX, vpY, vpW, vpH, GL.GL_RGBA, GL.GL_UNSIGNED_BYTE, byteBuf);
+        gl.glReadPixels(vpX, vpY, vpW, vpH, glFormat, dataType, byteBuf);
+    }
+    
+     public void readFrameBufferWithFormat(FrameBuffer fb, ByteBuffer byteBuf, Image.Format format) {         
+        GLImageFormat glFormat = texUtil.getImageFormatWithError(format, false);
+        readFrameBufferWithGLFormat(fb, byteBuf, glFormat.format, glFormat.dataType);
     }
 
     private void deleteRenderBuffer(FrameBuffer fb, RenderBuffer rb) {

jme3-core/src/main/java/com/jme3/system/NullRenderer.java

@@ -161,4 +161,7 @@ public class NullRenderer implements Renderer {
     public void setLinearizeSrgbImages(boolean linearize) {    
     }
 
+    public void readFrameBufferWithFormat(FrameBuffer fb, ByteBuffer byteBuf, Image.Format format) {        
+    }
+
 }

jme3-ios/src/main/java/com/jme3/renderer/ios/IGLESShaderRenderer.java

@@ -2593,4 +2593,8 @@ public class IGLESShaderRenderer implements Renderer {
     public void setLinearizeSrgbImages(boolean linearize) {
       
     }
+    
+    public void readFrameBufferWithFormat(FrameBuffer fb, ByteBuffer byteBuf, Image.Format format) {
+        throw new UnsupportedOperationException("Not supported yet. URA will make that work seamlessly"); 
+    }
 }

jme3-jogl/src/main/java/com/jme3/renderer/jogl/JoglRenderer.java

@@ -2713,4 +2713,8 @@ public class JoglRenderer implements Renderer {
 	public void setLinearizeSrgbImages(boolean linearize) {
         linearizeSrgbImages = linearize;
     }
+
+    public void readFrameBufferWithFormat(FrameBuffer fb, ByteBuffer byteBuf, Image.Format format) {
+        throw new UnsupportedOperationException("Not supported yet. URA will make that work seamlessly"); 
+    }
 }