Camera: support devices without accelerated GL

Platforms without a GPU such as the msm7x25 (or that for some reason are
missing an EGL library) don't have a stencil, and have limited alpha
capabilities. This patch adds support for those devices via a
"softwareGLOnly" build-time config option.

Change-Id: Iaad6fe3880dc392315bc930050bf53b0561746e3

res/values/config.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+/*
+** Copyright 2009, The Android Open Source Project
+**
+** Licensed under the Apache License, Version 2.0 (the "License"); 
+** you may not use this file except in compliance with the License. 
+** You may obtain a copy of the License at 
+**
+**     http://www.apache.org/licenses/LICENSE-2.0 
+**
+** Unless required by applicable law or agreed to in writing, software 
+** distributed under the License is distributed on an "AS IS" BASIS, 
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
+** See the License for the specific language governing permissions and 
+** limitations under the License.
+*/
+-->
+
+<!-- These resources are around just to allow their values to be customized
+     for different hardware and product builds. -->
+<resources>
+	<!-- set this to true if the device doesn't have a GPU, or an EGL
+	     library is for some reason unavailable -->
+	<bool name="softwareGLOnly">false</bool>
+</resources>

src/com/android/camera/ui/GLRootView.java

@@ -17,6 +17,7 @@
 package com.android.camera.ui;
 
 import com.android.camera.Util;
+import com.android.camera.R;
 
 import android.app.Activity;
 import android.content.Context;
@@ -174,7 +175,11 @@ public void runInGLThread(Runnable runnable) {
 
     private void initialize() {
         mFlags |= FLAG_INITIALIZED;
-        setEGLConfigChooser(8, 8, 8, 8, 0, 4);
+        if (getResources().getBoolean(R.bool.softwareGLOnly)) {
+            setEGLConfigChooser(8, 8, 8, 8, 0, 0);
+        } else {
+            setEGLConfigChooser(8, 8, 8, 8, 0, 4);
+        }
         getHolder().setFormat(PixelFormat.TRANSLUCENT);
         setZOrderOnTop(true);
 
@@ -441,7 +446,11 @@ public void onDrawFrame(GL10 gl) {
         clearClip();
         gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_STENCIL_BUFFER_BIT);
         gl.glEnable(GL11.GL_BLEND);
-        gl.glBlendFunc(GL11.GL_ONE, GL11.GL_ONE_MINUS_SRC_ALPHA);
+        if (getResources().getBoolean(R.bool.softwareGLOnly)) {
+            gl.glBlendFunc(GL11.GL_ONE, GL11.GL_ONE);
+        } else {
+            gl.glBlendFunc(GL11.GL_ONE, GL11.GL_ONE_MINUS_SRC_ALPHA);
+        }
 
         mAnimationTime = SystemClock.uptimeMillis();
         if (mContentView != null) {

src/com/android/camera/ui/PopupWindow.java

@@ -16,6 +16,8 @@
 
 package com.android.camera.ui;
 
+import com.android.camera.R;
+
 import android.graphics.Rect;
 import android.view.View.MeasureSpec;
 import android.view.animation.AlphaAnimation;
@@ -139,7 +141,11 @@ protected void renderBackground(GLRootView root, GL11 gl) {
 
         gl.glBlendFunc(GL11.GL_ONE, GL11.GL_ZERO);
         backup.draw(root, aXoffset, aYoffset, aWidth, aHeight, 1);
-        gl.glBlendFunc(GL11.GL_ONE, GL11.GL_ONE_MINUS_SRC_ALPHA);
+        if (getGLRootView().getContext().getResources().getBoolean(R.bool.softwareGLOnly)) {
+            gl.glBlendFunc(GL11.GL_ONE, GL11.GL_ONE);
+        } else {
+            gl.glBlendFunc(GL11.GL_ONE, GL11.GL_ONE_MINUS_SRC_ALPHA);
+        }
     }
 
     public void setContent(GLView content) {