把Android原生的View渲染到OpenGL Texture.docx

把Android原生的View渲染到OpenGL Texture最近要把Android 原生的View渲染到OpenGL GLSurfaceView中，起初想到的是截图的方法，也就是把View截取成bitmap后，再把Bitmap渲染到OpenGL中；但是明显这种方法是不可行的，面对一些高速动态更新的View，只有不停的对view 进行截图才能渲染出原生View的效果。通过大量的Google终于在国外的网站找到了一个做过类似的先例。不过经过测试该方法只能渲染直接父类为View的view，也就是只能渲染一层View（如progressbar，没不能添加child的view），当该原生Android View包含很多子view时（也就是根View为FramLayout、或者linearLayout之类），无法实时的监听到View动态改变，OpenGL中只能不停的渲染该view，才能渲染出原生View的效果。但是这样一来不同的渲染会耗费大量的资源，降低应用程序的效率。理想中的话，是监听到了该View的内容或者其子view 的内容发生了变化(如：View中的字幕发生滚动)才进行渲染。经过接近两周的努力我终于完美地实现了该效果，既然是站在别人的基础上得来的成果，那么该方法就应当被共享，所以产生了此文，不过只支持api 15以上的步骤一:重写根View1.设置该View 绘制自己：java view plain copy 在CODE上查看代码片派生到我的代码片setWillNotDraw(false);2.监听View的变化，重写View，用ViewTreeObServer来监听，方法如下：java view plain copy 在CODE上查看代码片派生到我的代码片private void addOnPreDrawListener() if (Build.VERSION.SDK_INT = Build.VERSION_CODES.HONEYCOMB) final ViewTreeObserver mObserver = getViewTreeObserver();if (mObserver != null) mObserver.addOnPreDrawListener(new OnPreDrawListener() Overridepublic boolean onPreDraw() if (isDirty() /View或者子view发生变化invalidate();return true;);3.重写该View的onDraw方法:java view plain copy 在CODE上查看代码片派生到我的代码片Overrideprotected void onDraw(Canvas canvas) try if (mSurface != null) Canvas surfaceCanvas = mSurface.lockCanvas(null);super.dispatchDraw(surfaceCanvas);mSurface.unlockCanvasAndPost(surfaceCanvas);mSurface.release();mSurface = null;mSurface = new Surface(mSurfaceTexture); catch (OutOfResourcesException e) e.printStackTrace();步骤二：GLSurfaceView.Rendererjava view plain copy 在CODE上查看代码片派生到我的代码片class CustomRenderer implements GLSurfaceView.Renderer int glSurfaceTex;private final int GL_TEXTURE_EXTERNAL_OES = 0x8D65;long currentTime;long previousTime;boolean b = false;int frameCount = 0;DirectDrawer mDirectDrawer;ActivityManager activityManager;MemoryInfo _memoryInfo;/ Fixed valuesprivate int TEXTURE_WIDTH = 360;private int TEXTURE_HEIGHT = 360;Context context;private LauncherAppWidgetHostView addedWidgetView;private SurfaceTexture surfaceTexture = null;private Surface surface;float fps;public CustomRenderer(Context context, LauncherAppWidgetHostView addedWidgetView, Display mDisplay)this.context = context;this.addedWidgetView = addedWidgetView;TEXTURE_WIDTH = mDisplay.getWidth();TEXTURE_HEIGHT = mDisplay.getHeight();_memoryInfo = new MemoryInfo();activityManager = (ActivityManager) context.getApplicationContext().getSystemService(Context.ACTIVITY_SERVICE);Overridepublic void onDrawFrame(GL10 gl) synchronized (this) surfaceTexture.updateTexImage();activityManager.getMemoryInfo(_memoryInfo);GLES20.glClearColor(0.0f, 0.0f, 1.0f, 1.0f);GLES20.glClear(GLES20.GL_DEPTH_BUFFER_BIT | GLES20.GL_COLOR_BUFFER_BIT);GLES20.glEnable(GLES20.GL_BLEND);GLES20.glBlendFunc(GLES20.GL_ONE, GLES20.GL_ONE_MINUS_SRC_ALPHA);float mtx = new float16;surfaceTexture.getTransformMatrix(mtx);mDirectDrawer.draw(mtx);calculateFps();/getAppMemorySize();/getRunningAppProcessInfo();/Log.v(onDrawFrame, FPS: + Math.round(fps) + , availMem: + Math.round(_memoryInfo.availMem / 1048576) + MB);private void getAppMemorySize()ActivityManager mActivityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);android.os.Debug.MemoryInfo memoryInfos = mActivityManager.getProcessMemoryInfo(new intandroid.os.Process.myPid();int size = memoryInfos0.dalvikPrivateDirty;Log.w(getAppMemorySize, size / 1024 + MB);private void getRunningAppProcessInfo() ActivityManager mActivityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);/获得系统里正在运行的所有进程List runningAppProcessesList = mActivityManager.getRunningAppProcesses();for (RunningAppProcessInfo runningAppProcessInfo : runningAppProcessesList) / 进程ID号int pid = runningAppProcessInfo.pid;/ 用户IDint uid = runningAppProcessInfo.uid;/ 进程名String processName = runningAppProcessIcessName;/ 占用的内存int pids = new int pid;Debug.MemoryInfo memoryInfo = mActivityManager.getProcessMemoryInfo(pids);int memorySize = memoryInfo0.dalvikPrivateDirty;System.out.println(processName=+processName+,currentPid: + pid= +android.os.Process.myPid()+-+pid+,uid=+uid+,memorySize=+memorySize+kb);Overridepublic void onSurfaceCreated(GL10 gl, EGLConfig config) surface = null;surfaceTexture = null;glSurfaceTex = Engine_CreateSurfaceTexture(TEXTURE_WIDTH, TEXTURE_HEIGHT);Log.d(GLES20Ext, glSurfaceTex + glSurfaceTex);if (glSurfaceTex 0) surfaceTexture = new SurfaceTexture(glSurfaceTex);surfaceTexture.setDefaultBufferSize(TEXTURE_WIDTH, TEXTURE_HEIGHT);surface = new Surface(surfaceTexture);addedWidgetView.setSurface(surface);addedWidgetView.setSurfaceTexture(surfaceTexture);/addedWidgetView.setSurfaceTexture(surfaceTexture);mDirectDrawer = new DirectDrawer(glSurfaceTex);float calculateFps() frameCount+;if (!b) b = true;previousTime = System.currentTimeMillis();long intervalTime = System.currentTimeMillis() - previousTime;if (intervalTime = 1000) b = false;fps = frameCount / (intervalTime / 1000f);frameCount = 0;Log.w(calculateFps, FPS: + fps);return fps;int Engine_CreateSurfaceTexture(int width, int height) /* Create our texture. This has to be done each time the surface is* created.*/int textures = new int1;GLES20.glGenTextures(1, textures, 0);glSurfaceTex = textures0;if (glSurfaceTex 0) GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, glSurfaceTex);/ Notice the use of GL_TEXTURE_2D for texture creationGLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGB, width, height, 0, GLES20.GL_RGB, GLES20.GL_UNSIGNED_BYTE, null);GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_CLAMP_TO_EDGE);GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_CLAMP_TO_EDGE);return glSurfaceTex;Overridepublic void onSurfaceChanged(GL10 gl, int width, int height) java view plain copy 在CODE上查看代码片派生到我的代码片public class DirectDrawer private final String vertexShaderCode =attribute vec4 vPosition; +attribute vec2 inputTextureCoordinate; +varying vec2 textureCoordinate; +void main() +gl_Position = vPosition;+textureCoordinate = inputTextureCoordinate; +;private final String fragmentShaderCode =#extension GL_OES_EGL_image_external : requiren+precision mediump float; +varying vec2 textureCoordinate;n +uniform samplerExternalOES s_texture;n +void main() + gl_FragColor = texture2D( s_texture, textureCoordinate );n +;private FloatBuffer vertexBuffer, textureVerticesBuffer;private ShortBuffer drawListBuffer;private final int mProgram;private int mPositionHandle;private int mTextureCoordHandle;private short drawOrder = 0, 1, 2, 0, 2, 3 ; / order to draw vertices/ number of coordinates per vertex in this arrayprivate static final int COORDS_PER_VERTEX = 2;private final int vertexStride = COORDS_PER_VERTEX * 4; / 4 bytes per vertexstatic float squareCoords = -1.0f, 0.0f,-1.0f, -2.2f,1.0f, -2.2f,1.0f, 0.0f,;static float textureVertices = 0f, 0f,0f, 1f,1f, 1f,1f, 0f,;private int texture;public DirectDrawer(int texture)this.texture = texture;/ initialize vertex byte buffer for shape coordinatesByteBuffer bb = ByteBuffer.allocateDirect(squareCoords.length * 4);bb.order(ByteOrder.nativeOrder();vertexBuffer = bb.asFloatBuffer();vertexBuffer.put(squareCoords);vertexBuffer.position(0);/ initialize byte buffer for the draw listByteBuffer dlb = ByteBuffer.allocateDirect(drawOrder.length * 2);dlb.order(ByteOrder.nativeOrder();drawListBuffer = dlb.asShortBuffer();drawListBuffer.put(drawOrder);drawListBuffer.position(0);ByteBuffer bb2 = ByteBuffer.allocateDirect(textureVertices.length * 4);bb2.order(ByteOrder.nativeOrder();textureVerticesBuffer = bb2.asFloatBuffer();textureVerticesBuffer.put(textureVertices);textureVerticesBuffer.position(0);int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);int fragmentShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderCode);mProgram = GLES20.glCreateProgram(); / create empty OpenGL ES ProgramGLES20.glAttachShader(mProgram, vertexShader); / add the vertex shader to programGLES20.glAttachShader(mProgram, fragmentShader); / add the fragment shader to programGLES20.glLinkProgram(mProgram); / creates OpenGL ES program executablespublic void draw(float mtx)GLES20.glUseProgram(mProgram);GLES20.glActiveTexture(GLES20.GL_TEXTURE0);GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, texture);/ get handle to vertex shaders vPosition membermPositionHandle = GLES20.glGetAttribLocation(mProgram, vPosition);/ Enable a handle to the triangle verticesGLES20.glEnableVertexAttribArray(mPositionHandle);/ Prepare the coordinate dataGLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, vertexStride, vertexBuffer);mTextureCoordHandle = GLES20.glGetAttribLocation(mProgram, inputTextureCoordinate);GLES20.glEnableVertexAttribArray(mTextureCoordHandle);/ textureVerticesBuffer.clear();/ textureVerticesBuffer.put( transformTextureCoordinates(/ textureVertices, mtx );/ textureVerticesBuffer.position(0);GLES20.glVertexAttribPointer(mTextureCoordHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, vertexStride, textureVerticesBuffer);GLES20.glDrawElements(GLES20.GL_TRIANGLES, drawOrder.length, GLES20.GL_UNSIGNED_SHORT, drawListBuffer);/ Disable vertex arrayGLES20.glDisableVertexAttribArray(mPositionHandle);GLES20.glDisableVertexAttribArray(mTextureCoordHandle);private int loadShader(int type, String shaderCode)/ create a vertex shader type (GLES20.GL_VERTEX_SHADER)