GlConfigChooser.java

package org.oscim.android.gl;

import javax.microedition.khronos.egl.EGL10;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.egl.EGLDisplay;

import android.opengl.GLSurfaceView;

public class GlConfigChooser implements GLSurfaceView.EGLConfigChooser {

	@Override
	public EGLConfig chooseConfig(EGL10 egl, EGLDisplay display) {
		int[] val = new int[1];

		// Try to find a normal multisample configuration first.
		int[] configSpec = {
		        EGL10.EGL_RED_SIZE, 5,
		        EGL10.EGL_GREEN_SIZE, 6,
		        EGL10.EGL_BLUE_SIZE, 5,
		        EGL10.EGL_ALPHA_SIZE, 8,
		        EGL10.EGL_DEPTH_SIZE, 16,
		        // Requires that setEGLContextClientVersion(2) is called on the view.
		        EGL10.EGL_RENDERABLE_TYPE, 4 /* EGL_OPENGL_ES2_BIT */,
		        EGL10.EGL_STENCIL_SIZE, 8,
		        EGL10.EGL_NONE };

		if (!egl.eglChooseConfig(display, configSpec, null, 0, val)) {
			throw new IllegalArgumentException("eglChooseConfig failed");
		}
		int numConfigs = val[0];

		if (numConfigs <= 0) {

			configSpec = new int[] {
			        // EGL10.EGL_RENDERABLE_TYPE, 4, EGL10.EGL_NONE };
			        EGL10.EGL_RED_SIZE, 8,
			        EGL10.EGL_GREEN_SIZE, 8,
			        EGL10.EGL_BLUE_SIZE, 8,
			        EGL10.EGL_ALPHA_SIZE, 8,
			        EGL10.EGL_DEPTH_SIZE, 16,
			        EGL10.EGL_RENDERABLE_TYPE, 4 /* EGL_OPENGL_ES2_BIT */,
			        EGL10.EGL_STENCIL_SIZE, 8,
			        EGL10.EGL_NONE };

			if (!egl.eglChooseConfig(display, configSpec, null, 0, val)) {
				throw new IllegalArgumentException("eglChooseConfig failed");
			}
			numConfigs = val[0];

			if (numConfigs <= 0) {
				throw new IllegalArgumentException("No configs match configSpec");
			}
		}

		// Get all matching configurations.
		EGLConfig[] configs = new EGLConfig[numConfigs];
		if (!egl.eglChooseConfig(display, configSpec, configs, numConfigs, val)) {
			throw new IllegalArgumentException("data eglChooseConfig failed");
		}

		// CAUTION! eglChooseConfigs returns configs with higher bit depth
		// first: Even though we asked for rgb565 configurations, rgb888
		// configurations are considered to be "better" and returned first.
		// You need to explicitly filter the data returned by eglChooseConfig!

		EGLConfig config = configs.length > 0 ? configs[0] : null;
		if (config == null) {
			throw new IllegalArgumentException("No config chosen");
		}
		return config;
	}
}