Clarify the default algorithm used to choose an EGLConfig.
Explicitly default to an RGB_565 android.view.Surface.
diff --git a/opengl/java/android/opengl/GLSurfaceView.java b/opengl/java/android/opengl/GLSurfaceView.java
index 71411ef..882cbc5 100644
--- a/opengl/java/android/opengl/GLSurfaceView.java
+++ b/opengl/java/android/opengl/GLSurfaceView.java
@@ -30,6 +30,7 @@
import android.content.Context;
import android.content.pm.ConfigurationInfo;
+import android.graphics.PixelFormat;
import android.os.SystemProperties;
import android.util.AttributeSet;
import android.util.Log;
@@ -75,15 +76,23 @@
* <li>{@link #setGLWrapper(GLWrapper)}
* </ul>
* <p>
- * <h4>Choosing an EGL Configuration</h4>
- * A given Android device may support multiple possible types of drawing surfaces.
- * The available surfaces may differ in how may channels of data are present, as
- * well as how many bits are allocated to each channel. Therefore, the first thing
- * GLSurfaceView has to do when starting to render is choose what type of surface to use.
+ * <h4>Specifying the android.view.Surface</h4>
+ * By default GLSurfaceView will create a PixelFormat.RGB_565 format surface. If a translucent
+ * surface is required, call getHolder().setFormat(PixelFormat.TRANSLUCENT).
+ * The exact format of a TRANSLUCENT surface is device dependent, but it will be
+ * a 32-bit-per-pixel surface with 8 bits per component.
* <p>
- * By default GLSurfaceView chooses an available surface that's closest to a 16-bit R5G6B5 surface
- * with a 16-bit depth buffer and no stencil. If you would prefer a different surface (for example,
- * if you do not need a depth buffer) you can override the default behavior by calling one of the
+ * <h4>Choosing an EGL Configuration</h4>
+ * A given Android device may support multiple EGLConfig rendering configurations.
+ * The available configurations may differ in how may channels of data are present, as
+ * well as how many bits are allocated to each channel. Therefore, the first thing
+ * GLSurfaceView has to do when starting to render is choose what EGLConfig to use.
+ * <p>
+ * By default GLSurfaceView chooses a EGLConfig that has an RGB_656 pixel format,
+ * with at least a 16-bit depth buffer and no stencil.
+ * <p>
+ * If you would prefer a different EGLConfig
+ * you can override the default behavior by calling one of the
* setEGLConfigChooser methods.
* <p>
* <h4>Debug Behavior</h4>
@@ -211,6 +220,7 @@
// underlying surface is created and destroyed
SurfaceHolder holder = getHolder();
holder.addCallback(this);
+ holder.setFormat(PixelFormat.RGB_565);
// setType is not needed for SDK 2.0 or newer. Uncomment this
// statement if back-porting this code to older SDKs.
// holder.setType(SurfaceHolder.SURFACE_TYPE_GPU);
@@ -331,8 +341,9 @@
* is called.
* <p>
* If no setEGLConfigChooser method is called, then by default the
- * view will choose a config as close to 16-bit RGB as possible, with
- * a depth buffer as close to 16 bits as possible.
+ * view will choose an EGLConfig that is compatible with the current
+ * android.view.Surface, with a depth buffer depth of
+ * at least 16 bits.
* @param configChooser
*/
public void setEGLConfigChooser(EGLConfigChooser configChooser) {
@@ -348,9 +359,9 @@
* called, it must be called before {@link #setRenderer(Renderer)}
* is called.
* <p>
- * If no setEGLConfigChooser method is called, then by default the
- * view will choose a config as close to 16-bit RGB as possible, with
- * a depth buffer as close to 16 bits as possible.
+ * If no setEGLConfigChooser method is called, then by default the
+ * view will choose an RGB_565 surface with a depth buffer depth of
+ * at least 16 bits.
*
* @param needDepth
*/
@@ -360,15 +371,15 @@
/**
* Install a config chooser which will choose a config
- * with at least the specified component sizes, and as close
- * to the specified component sizes as possible.
+ * with at least the specified depthSize and stencilSize,
+ * and exactly the specified redSize, greenSize, blueSize and alphaSize.
* <p>If this method is
* called, it must be called before {@link #setRenderer(Renderer)}
* is called.
* <p>
* If no setEGLConfigChooser method is called, then by default the
- * view will choose a config as close to 16-bit RGB as possible, with
- * a depth buffer as close to 16 bits as possible.
+ * view will choose an RGB_565 surface with a depth buffer depth of
+ * at least 16 bits.
*
*/
public void setEGLConfigChooser(int redSize, int greenSize, int blueSize,
@@ -775,6 +786,10 @@
}
}
+ /**
+ * Choose a configuration with exactly the specified r,g,b,a sizes,
+ * and at least the specified depth and stencil sizes.
+ */
private class ComponentSizeChooser extends BaseConfigChooser {
public ComponentSizeChooser(int redSize, int greenSize, int blueSize,
int alphaSize, int depthSize, int stencilSize) {
@@ -798,14 +813,12 @@
@Override
public EGLConfig chooseConfig(EGL10 egl, EGLDisplay display,
EGLConfig[] configs) {
- EGLConfig closestConfig = null;
- int closestDistance = 1000;
- for(EGLConfig config : configs) {
+ for (EGLConfig config : configs) {
int d = findConfigAttrib(egl, display, config,
EGL10.EGL_DEPTH_SIZE, 0);
int s = findConfigAttrib(egl, display, config,
EGL10.EGL_STENCIL_SIZE, 0);
- if (d >= mDepthSize && s>= mStencilSize) {
+ if ((d >= mDepthSize) && (s >= mStencilSize)) {
int r = findConfigAttrib(egl, display, config,
EGL10.EGL_RED_SIZE, 0);
int g = findConfigAttrib(egl, display, config,
@@ -814,17 +827,13 @@
EGL10.EGL_BLUE_SIZE, 0);
int a = findConfigAttrib(egl, display, config,
EGL10.EGL_ALPHA_SIZE, 0);
- int distance = Math.abs(r - mRedSize)
- + Math.abs(g - mGreenSize)
- + Math.abs(b - mBlueSize)
- + Math.abs(a - mAlphaSize);
- if (distance < closestDistance) {
- closestDistance = distance;
- closestConfig = config;
+ if ((r == mRedSize) && (g == mGreenSize)
+ && (b == mBlueSize) && (a == mAlphaSize)) {
+ return config;
}
}
}
- return closestConfig;
+ return null;
}
private int findConfigAttrib(EGL10 egl, EGLDisplay display,
@@ -847,18 +856,13 @@
}
/**
- * This class will choose a supported surface as close to
- * RGB565 as possible, with or without a depth buffer.
+ * This class will choose a RGB_565 surface with
+ * or without a depth buffer.
*
*/
private class SimpleEGLConfigChooser extends ComponentSizeChooser {
public SimpleEGLConfigChooser(boolean withDepthBuffer) {
- super(4, 4, 4, 0, withDepthBuffer ? 16 : 0, 0);
- // Adjust target values. This way we'll accept a 4444 or
- // 555 buffer if there's no 565 buffer available.
- mRedSize = 5;
- mGreenSize = 6;
- mBlueSize = 5;
+ super(5, 6, 5, 0, withDepthBuffer ? 16 : 0, 0);
}
}