How can I put a view on top of a glSurfaceView with a transparent background?

Question

My app is composed (from back to front) of an image background, then a glSurfaceView containing a 3D object and on the top 2 buttons. I want the background of the GLSurfaceView to be transparent and see the image behind.

I've tried two solutions, but none of them is satisfying :

mGLSurfaceView = new GLSurfaceView(mContext);
mGLSurfaceView.setEGLContextClientVersion(2);           
mGLSurfaceView.setEGLConfigChooser(8, 8, 8, 8, 16, 0);
mGLSurfaceView.getHolder().setFormat(PixelFormat.TRANSLUCENT);
mGLSurfaceView.setZOrderOnTop(true);
mGLSurfaceView.setRenderer(mRenderer);

In this case, I can see the background, but the 3D object is floating on the top of all the other layouts, sometimes hiding the buttons.

mGLSurfaceView = new GLSurfaceView(mContext);
mGLSurfaceView.setEGLContextClientVersion(2);           
mGLSurfaceView.setEGLConfigChooser(8, 8, 8, 8, 16, 0);
mGLSurfaceView.getHolder().setFormat(PixelFormat.TRANSLUCENT);
mGLSurfaceView.setZOrderMediaOverlay(true);
mGLSurfaceView.setRenderer(mRenderer);

In that case, I can see the buttons, but the GLSurfaceView is no longer transparent and I cannot see the image background. I've parsed all the other topics, but none of them gave me any satisfying answer.

I'm also crusading for an answer to this problem. As far as I can tell it is simply impossible on some devices. On other devices the second case does result in a transparant SurfaceView. — Paul Wagener, Nov 30 '13 at 14:19
Strangely I don't have this problem on Android 2.3. Only on 4.* — Paul Wagener, Jan 08 '14 at 19:36
Try using `TextureView` which was introduced in 4.0 and has better performance. — Shakti, Jan 27 '14 at 04:02
I am just wondering why don't you draw the background in your SurfaceView? @Gerard — Sherif elKhatib, Jan 29 '14 at 23:05
You mean creating a 2D textured object in OpenGL? That is what I am doing currently, but the performance is much worse (loading texture is a pretty heavy operation performance-wise). Thanks for you help though — Gerard, Jan 30 '14 at 13:17

score 1 · Answer 1 · edited May 23 '17 at 10:33

1

final GLSurfaceView glView = (GLSurfaceView) findViewById(R.id.glView);

glView.setZOrderOnTop(true);
glView.setEGLConfigChooser(8, 8, 8, 8, 16, 0);
glView.getHolder().setFormat(PixelFormat.RGBA_8888);
glView.setRenderer(new MyRenderer());
glView.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);

given by SO post: Android GLSurfaceView transparent background without setZOrderonTop and the original blog post: How to set a transparent GLSurfaceView

edited May 23 '17 at 10:33

Community

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answered Jan 27 '14 at 07:05

Fred Grott

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Finally! Thank you! Spent all day Friday trying to figure this out. – TJ Biddle May 18 '15 at 16:12
Glad to have an answer for you, TJ Biddle – Fred Grott May 20 '15 at 19:41

score 0 · Answer 2 · answered Feb 22 '16 at 15:36

0

setZOrderOnTop() works, but it means that you can't place any graphics on top of this SurfaceView, which is unfortunate.

answered Feb 22 '16 at 15:36

Manuel Schmitzberger

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How can I put a view on top of a glSurfaceView with a transparent background?

2 Answers2