Android OpenGL ES Transparent Background

mattbasta picture mattbasta · Jan 9, 2010 · Viewed 24.9k times · Source

I'm building an Android app that takes advantage of OpenGL. As it stands, the background for the GLSurfaceView is dynamically generated by my code and loaded in as a texture and drawn with glDrawTexfOES. Which is "ok", but I can simply display the image much more smoothly to its own surface (without OpenGL). Is there any way that I can make the background of a GLSurfaceView transparent? I've heard some rumors that this can be done with setEGLConfigChooser, but I haven't found any confirmation. Ultimately, I'd like to take a surface which I'm drawing to and put the GLSurfaceView over it to achieve a layered effect.

I know this is a tricky and is quite possibly infeasible, but any input is appreciated. Thanks in advance.

Answer

mattbasta picture mattbasta · Feb 4, 2010

Just some simple changes that I did to get this to work.

On my GLSurfaceView.Renderer:

public void onSurfaceCreated(GL10 gl, EGLConfig config) {
    gl.glDisable(GL10.GL_DITHER);
    gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT,
            GL10.GL_FASTEST);

     gl.glClearColor(0,0,0,0);
     gl.glEnable(GL10.GL_CULL_FACE);
     gl.glShadeModel(GL10.GL_SMOOTH);
     gl.glEnable(GL10.GL_DEPTH_TEST);
}

On my GLSurfaceView:

setEGLConfigChooser(8, 8, 8, 8, 16, 0);
getHolder().setFormat(PixelFormat.TRANSLUCENT);