[android-developers] OpenGL ES 1.1 with alpha channel

I have a problem with setting up OpenGL ES 1.1 with alpha channel support.

First of all: I need an alpha channel within OpenGL ES for performing alpha masking and blending effects. My game uses a texture with alpha channel for masking another texture. This only happens to work when I initialize OpenGL ES with the following configuration:

glView.setEGLConfigChooser(8, 8, 8, 8, 0, 8);

I could use the stencil buffer instead and parts of my game do that, too. However, my Nexus 7 tablet crashes pretty hard with a colorfully distorted screen when I use the stencil buffer in conjunction with alpha testing (which is necessary for discarding transparent pixels in the masking texture):

gl.glEnable(GL10.GL_ALPHA_TEST);
gl.glAlphaFunc(GL10.GL_GREATER, 0.05f);

Romain Guy says here that the alpha channel set in setEGLConfigChooser does not need to be used unless the window is translucent. However, when I compile my game with:

glView.setEGLConfigChooser(8, 8, 8, 0, 0, 8); // alpha = 0

My texture masking effect does not work anymore. Instead I can only see the unmasked texture hovering as a square on the screen. All other textures with alpha channel are rendered correctly but only when I don't try to alpha-mask them.

I could leave the configuration with 8 bits alpha channel. However, then I get on some older devices crashes with an EGL_BAD_MATCH  error because their surface view apparently only supports RGB565 or maybe even something worse than that.

I tried fixing the problem as follows:

glView.setEGLConfigChooser(5, 6, 5, 8, 0, 8);

But that does not work either (config chooser cannot find a matching configuration). What can I do in this situation? How can I keep my alpha channel within OpenGL ES (I don't need it for the surface nor the window) and make older devices happy without crashing right on initialization?

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