- SurfaceView 预览相机，适用于单纯预览，或者一边预览一边将数据发送到服务器
public class SurfaceViewCameraActivity extends AppCompatActivity
implements SurfaceHolder.Callback, Camera.PreviewCallback {
private Camera mCamera;
private SurfaceView mSurfaceView;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mSurfaceView = new SurfaceView(this);
mSurfaceView.getHolder().addCallback(this);
setContentView(mSurfaceView);
}
@Override
public void surfaceCreated(@NonNull SurfaceHolder holder) {
mCamera = Camera.open();
try {
mCamera.setPreviewCallback(this);
mCamera.setPreviewDisplay(holder);
mCamera.startPreview();
} catch (IOException ioe) {
// Something bad happened
}
}
@Override
public void surfaceChanged(@NonNull SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceDestroyed(@NonNull SurfaceHolder holder) {
mCamera.setPreviewCallback(null);
mCamera.stopPreview();
mCamera.release();
}
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
// encode and upload to server.
}
}
- TextureView 预览相机，同 1
public class TextureViewCameraActivity extends AppCompatActivity
implements TextureView.SurfaceTextureListener, Camera.PreviewCallback {
private Camera mCamera;
private TextureView mTextureView;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mTextureView = new TextureView(this);
mTextureView.setSurfaceTextureListener(this);
setContentView(mTextureView);
}
@Override
public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
mCamera = Camera.open();
try {
mCamera.setPreviewCallback(this);
mCamera.setPreviewTexture(surface);
mCamera.startPreview();
} catch (IOException ioe) {
// Something bad happened
}
}
@Override
public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {
// Ignored, Camera does all the work for us
}
@Override
public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
mCamera.setPreviewCallback(null);
mCamera.stopPreview();
mCamera.release();
return true;
}
@Override
public void onSurfaceTextureUpdated(SurfaceTexture surface) {
// Invoked every time there's a new Camera preview frame
}
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
// encode and upload to server.
}
}
- 相机数据先到单独的 SurfaceTexture（可以直接得到一个纹理，这里并没有直接用这个纹理，而只是借用了 SurfaceTexture 的 Buffer，否则 Camera 的数据没地方送，导致 onPreviewFrame() 回调不会得到调用），再到 SurfaceView，适用于先得到相机数据并将数据进行处理后再进行预览，比如加滤镜效果。
这里的示例是使用的 lockCanvas 得到 Canvas 对象进行绘制到 SurfaceView 中去的。也就是先拿到 data 数据，再对数据进行处理并转换为 Bitmap，然后通过 Canvas 绘制到 SurfaceView 或者 TextureView 上。
流程：data[] => SurfaceTexture 的 buffer => 数据处理 => 转换为 Bitmap => 绘制到 SurfaceView/TextureView 上
public class SurfaceTexture2SurfaceViewCameraActivity extends AppCompatActivity
implements SurfaceHolder.Callback, Camera.PreviewCallback {
private Camera mCamera;
private SurfaceView mSurfaceView;
private SurfaceTexture mSurfaceTexture;
private Rect mOriginalRect;
private Rect mRotatedRect;
private int mWidth;
private int mHeight;
private Bitmap mBitmap;
private byte[] mBuffer;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mSurfaceView = new SurfaceView(this);
mSurfaceView.getHolder().addCallback(this);
setContentView(mSurfaceView);
}
@Override
public void surfaceCreated(@NonNull SurfaceHolder holder) {
mSurfaceTexture = new SurfaceTexture(1);
mCamera = Camera.open();
try {
mCamera.setPreviewTexture(mSurfaceTexture);
} catch (IOException e) {
e.printStackTrace();
}
mWidth = mCamera.getParameters().getPreviewSize().width;
mHeight = mCamera.getParameters().getPreviewSize().height;
int bufferSize = mWidth * mHeight * ImageFormat.getBitsPerPixel(mCamera.getParameters().getPreviewFormat()) / 8;
mBuffer = new byte[bufferSize];
mCamera.addCallbackBuffer(mBuffer);
mCamera.setPreviewCallbackWithBuffer(this);
mCamera.startPreview();
}
@Override
public void surfaceChanged(@NonNull SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceDestroyed(@NonNull SurfaceHolder holder) {
mCamera.setPreviewCallbackWithBuffer(null);
mCamera.stopPreview();
mCamera.release();
}
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
camera.addCallbackBuffer(mBuffer);
if (null == mOriginalRect) {
mOriginalRect = new Rect(0, 0, mWidth, mHeight);
}
YuvImage image = new YuvImage(data, ImageFormat.NV21, mWidth, mHeight, null);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
image.compressToJpeg(mOriginalRect, 80, stream);
mBitmap = BitmapFactory.decodeByteArray(stream.toByteArray(), 0, stream.size());
try {
stream.close();
} catch (IOException e) {
e.printStackTrace();
}
int rotation = getWindowManager().getDefaultDisplay().getRotation();
int degree = -90 * rotation;
Matrix matrix = new Matrix();
matrix.postRotate(degree + 90);
mBitmap = Bitmap.createBitmap(mBitmap, 0, 0, mBitmap.getWidth(), mBitmap.getHeight(), matrix, true);
mBitmap = Bitmap.createScaledBitmap(mBitmap, mSurfaceView.getWidth(), mSurfaceView.getHeight(), true);
if (mRotatedRect == null) {
mRotatedRect = new Rect(0, 0, mBitmap.getWidth(), mBitmap.getHeight());
}
Canvas canvas = mSurfaceView.getHolder().lockCanvas();
canvas.drawBitmap(mBitmap, null, mRotatedRect, null);
mSurfaceView.getHolder().unlockCanvasAndPost(canvas);
}
}
- 相机数据先到单独的 SurfaceTexture，同 3
public class SurfaceTexture2TextureViewCameraActivity extends AppCompatActivity
implements TextureView.SurfaceTextureListener, Camera.PreviewCallback {
private Camera mCamera;
private TextureView mTextureView;
private SurfaceTexture mSurfaceTexture;
private Rect mOriginalRect;
private Rect mRotatedRect;
private int mWidth;
private int mHeight;
private Bitmap mBitmap;
private byte[] mBuffer;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mTextureView = new TextureView(this);
mTextureView.setSurfaceTextureListener(this);
setContentView(mTextureView);
}
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
camera.addCallbackBuffer(mBuffer);
if (null == mOriginalRect) {
mOriginalRect = new Rect(0, 0, mWidth, mHeight);
}
YuvImage image = new YuvImage(data, ImageFormat.NV21, mWidth, mHeight, null);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
image.compressToJpeg(mOriginalRect, 80, stream);
mBitmap = BitmapFactory.decodeByteArray(stream.toByteArray(), 0, stream.size());
try {
stream.close();
} catch (IOException e) {
e.printStackTrace();
}
int rotation = getWindowManager().getDefaultDisplay().getRotation();
int degree = -90 * rotation;
Matrix matrix = new Matrix();
matrix.postRotate(degree + 90);
mBitmap = Bitmap.createBitmap(mBitmap, 0, 0, mBitmap.getWidth(), mBitmap.getHeight(), matrix, true);
mBitmap = Bitmap.createScaledBitmap(mBitmap, mTextureView.getWidth(), mTextureView.getHeight(), true);
if (mRotatedRect == null) {
mRotatedRect = new Rect(0, 0, mBitmap.getWidth(), mBitmap.getHeight());
}
Canvas canvas = mTextureView.lockCanvas();
canvas.drawBitmap(mBitmap, null, mRotatedRect, null);
mTextureView.unlockCanvasAndPost(canvas);
}
@Override
public void onSurfaceTextureAvailable(@NonNull SurfaceTexture surface, int width, int height) {
mSurfaceTexture = new SurfaceTexture(1);
mCamera = Camera.open();
try {
mCamera.setPreviewTexture(mSurfaceTexture);
} catch (IOException e) {
e.printStackTrace();
}
mWidth = mCamera.getParameters().getPreviewSize().width;
mHeight = mCamera.getParameters().getPreviewSize().height;
int bufferSize = mWidth * mHeight * ImageFormat.getBitsPerPixel(mCamera.getParameters().getPreviewFormat()) / 8;
mBuffer = new byte[bufferSize];
mCamera.addCallbackBuffer(mBuffer);
mCamera.setPreviewCallbackWithBuffer(this);
mCamera.startPreview();
}
@Override
public void onSurfaceTextureSizeChanged(@NonNull SurfaceTexture surface, int width, int height) {
}
@Override
public boolean onSurfaceTextureDestroyed(@NonNull SurfaceTexture surface) {
mCamera.setPreviewCallbackWithBuffer(null);
mCamera.stopPreview();
mCamera.release();
return false;
}
@Override
public void onSurfaceTextureUpdated(@NonNull SurfaceTexture surface) {
}
}
- 其实无非就是想要对原始数据进行处理再进行绘制显示出来，所以也可以直接使用 GLSurfaceView 作为 Camera 的渲染目标（TextureView 需要自行创建 EGL 环境，如新建一个类 GLTextureView），把 data 数据传到 OpenGL 处理（调用 GLES20.glTexImage2D 方法传递数据），处理完毕（调用 GLES20.glDrawArrays 方法）即可自动更新到 GLSurfaceView 上。
流程：data[] => SurfaceTexture 的 buffer => OpenGL 处理并绘制到 GLSurfaceView/GLTextureView 上
/**
* 利用 OpenGL 处理原始数据并直接绘制到 GLSurfaceView 上，其实也是先转换成了纹理，
* 只是这里是手动将相机数据生成纹理，参考 {@link android.opengl.GLES20#glTexImage2D}
*/
public class HandleDataByOpenGLCameraActivity extends AppCompatActivity
implements GLSurfaceView.Renderer, Camera.PreviewCallback {
private Camera mCamera;
private GLSurfaceView mGLSurfaceView;
private SurfaceTexture mSurfaceTexture;
private IntBuffer mGLRgbBuffer;
private DirectDrawer mDrawer;
private int mWidth;
private int mHeight;
private final Object mLock = new Object();
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
initGLSurfaceView();
setContentView(mGLSurfaceView);
}
@Override
protected void onDestroy() {
super.onDestroy();
mCamera.setPreviewCallback(null);
mCamera.stopPreview();
mCamera.release();
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
GLES20.glClearColor(0f, 0f, 0f, 0f);
mCamera = Camera.open();
final Camera.Size previewSize = mCamera.getParameters().getPreviewSize();
mWidth = previewSize.width;
mHeight = previewSize.height;
try {
int[] textures = new int[1];
GLES20.glGenTextures(1, textures, 0);
mSurfaceTexture = new SurfaceTexture(textures[0]);
mCamera.setPreviewTexture(mSurfaceTexture);
} catch (IOException ioe) {
// Something bad happened
}
mCamera.startPreview();
mCamera.setPreviewCallback(this);
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
GLES20.glViewport(0, 0, width, height);
}
@Override
public void onDrawFrame(GL10 gl) {
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
if (mDrawer == null) {
mDrawer = new DirectDrawer();
mDrawer.init();
}
synchronized (mLock) {
// 将 glRgbBuffer 中的 RGBA 数据生成纹理
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, mWidth, mHeight,
0, GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, mGLRgbBuffer);
mDrawer.draw();
mGLSurfaceView.requestRender();
}
}
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
if (mGLRgbBuffer == null) {
mGLRgbBuffer = IntBuffer.allocate(mWidth * mHeight);
}
synchronized (mLock) {
// 将原始数据转换为 RGBA 数据，存放到 glRgbBuffer 中
GPUImageNativeLibrary.YUVtoRBGA(data, mWidth, mHeight, mGLRgbBuffer.array());
}
}
private void initGLSurfaceView() {
mGLSurfaceView = new GLSurfaceView(this);
mGLSurfaceView.setEGLContextClientVersion(2);
mGLSurfaceView.setEGLConfigChooser(8, 8, 8, 8, 16, 0);
mGLSurfaceView.getHolder().setFormat(PixelFormat.RGBA_8888);
mGLSurfaceView.setRenderer(this);
mGLSurfaceView.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
mGLSurfaceView.requestRender();
}
public static void checkError() {
int errorCode = GLES20.glGetError();
Log.d("hehe", "errorCode: " + errorCode, new Throwable());
}
/**
* 参考 VideoDumpView.java，注意这里用的是普通纹理 sampler2D
*/
private static class DirectDrawer {
private final String vertexShaderCode =
"attribute vec4 vPosition;\n" +
"attribute vec2 inputTextureCoordinate;\n" +
"varying vec2 textureCoordinate;\n" +
"void main() {\n" +
" gl_Position = vPosition;\n" +
" textureCoordinate = inputTextureCoordinate;\n" +
"}\n";
private final String fragmentShaderCode =
"precision mediump float;\n" +
"varying vec2 textureCoordinate;\n" +
"uniform sampler2D s_texture;\n" +
"void main() {\n" +
" gl_FragColor = texture2D( s_texture, textureCoordinate );\n" +
"}\n";
private int texture;
private FloatBuffer vertexBuffer;
private FloatBuffer textureVerticesBuffer;
private ShortBuffer drawListBuffer;
private int mProgram;
private int mPositionHandle;
private int mTextureCoordHandle;
private static final short DRAW_ORDER[] = {0, 1, 2, 0, 2, 3};
private static final int COORDS_PER_VERTEX = 2;
private static final int VERTEX_STRIDE = COORDS_PER_VERTEX * 4; // 4 bytes per vertex
private static float SQUARE_COORDS[] = {
-1.0f, 1.0f,
-1.0f, -1.0f,
1.0f, -1.0f,
1.0f, 1.0f,
};
private static float TEXTURE_VERTICES[] = {
0.0f, 1.0f,
1.0f, 1.0f,
1.0f, 0.0f,
0.0f, 0.0f,
};
public void init() {
createTexture();
createProgram();
}
public void draw() {
GLES20.glUseProgram(mProgram);
//使用纹理
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texture);
//顶点位置
mPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");
GLES20.glEnableVertexAttribArray(mPositionHandle);
GLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, VERTEX_STRIDE, vertexBuffer);
//纹理坐标
mTextureCoordHandle = GLES20.glGetAttribLocation(mProgram, "inputTextureCoordinate");
GLES20.glEnableVertexAttribArray(mTextureCoordHandle);
GLES20.glVertexAttribPointer(mTextureCoordHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, VERTEX_STRIDE, textureVerticesBuffer);
//绘制
GLES20.glDrawElements(GLES20.GL_TRIANGLES, DRAW_ORDER.length, GLES20.GL_UNSIGNED_SHORT, drawListBuffer);
//结束
GLES20.glDisableVertexAttribArray(mPositionHandle);
GLES20.glDisableVertexAttribArray(mTextureCoordHandle);
}
//编译着色器
private int loadShader(int type, String shaderCode) {
int shader = GLES20.glCreateShader(type);
GLES20.glShaderSource(shader, shaderCode);
GLES20.glCompileShader(shader);
return shader;
}
private void createTexture() {
int[] texture = new int[1];
GLES20.glGenTextures(1, texture, 0);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texture[0]);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, (float) GLES20.GL_LINEAR);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, (float) GLES20.GL_LINEAR);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_CLAMP_TO_EDGE);
this.texture = texture[0];
}
private void createProgram() {
//顶点坐标
ByteBuffer bb = ByteBuffer.allocateDirect(SQUARE_COORDS.length * 4);
bb.order(ByteOrder.nativeOrder());
vertexBuffer = bb.asFloatBuffer();
vertexBuffer.put(SQUARE_COORDS);
vertexBuffer.position(0);
//顶点绘制顺序
ByteBuffer dlb = ByteBuffer.allocateDirect(DRAW_ORDER.length * 2);
dlb.order(ByteOrder.nativeOrder());
drawListBuffer = dlb.asShortBuffer();
drawListBuffer.put(DRAW_ORDER);
drawListBuffer.position(0);
//纹理坐标
ByteBuffer bb2 = ByteBuffer.allocateDirect(TEXTURE_VERTICES.length * 4);
bb2.order(ByteOrder.nativeOrder());
textureVerticesBuffer = bb2.asFloatBuffer();
textureVerticesBuffer.put(TEXTURE_VERTICES);
textureVerticesBuffer.position(0);
//编译着色器
int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
int fragmentShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderCode);
mProgram = GLES20.glCreateProgram();
GLES20.glAttachShader(mProgram, vertexShader);
GLES20.glAttachShader(mProgram, fragmentShader);
GLES20.glLinkProgram(mProgram);
}
}
private static class GPUImageNativeLibrary {
public static void YUVtoRBGA(byte[] yuv, int width, int height, int[] rgbData) {
int sz;
int i;
int j;
int Y;
int Cr = 0;
int Cb = 0;
int pixPtr = 0;
int jDiv2 = 0;
int R = 0;
int G = 0;
int B = 0;
int cOff;
int w = width;
int h = height;
sz = w * h;
for (j = 0; j < h; j++) {
pixPtr = j * w;
jDiv2 = j >> 1;
for (i = 0; i < w; i++) {
Y = yuv[pixPtr];
if (Y < 0) Y += 255;
if ((i & 0x1) != 1) {
cOff = sz + jDiv2 * w + (i >> 1) * 2;
Cb = yuv[cOff];
if (Cb < 0) Cb += 127;
else Cb -= 128;
Cr = yuv[cOff + 1];
if (Cr < 0) Cr += 127;
else Cr -= 128;
}
//ITU-R BT.601 conversion
//
//R = 1.164*(Y-16) + 2.018*(Cr-128);
//G = 1.164*(Y-16) - 0.813*(Cb-128) - 0.391*(Cr-128);
//B = 1.164*(Y-16) + 1.596*(Cb-128);
//
Y = Y + (Y >> 3) + (Y >> 5) + (Y >> 7);
R = Y + (Cr << 1) + (Cr >> 6);
if (R < 0) R = 0;
else if (R > 255) R = 255;
G = Y - Cb + (Cb >> 3) + (Cb >> 4) - (Cr >> 1) + (Cr >> 3);
if (G < 0) G = 0;
else if (G > 255) G = 255;
B = Y + Cb + (Cb >> 1) + (Cb >> 4) + (Cb >> 5);
if (B < 0) B = 0;
else if (B > 255) B = 255;
rgbData[pixPtr++] = 0xff000000 + (R << 16) + (G << 8) + B;
}
}
}
}
}
附： SurfaceTexture 的使用，参考 TextureView.java 源码和 VideoDumpView.java 源码（/frameworks/base/media/tests/MediaDump/src/com/android/mediadump/）
- 既然用到了 SurfaceTexture，其实可以直接处理得到的纹理，而不需要处理其原始数据
/**
* 因为用到了 SurfaceTexture，所以原始数据已经转换成了纹理，所以可以不用处理原始数据，
* 直接利用 OpenGL 处理 SurfaceTexture 生成的纹理，然后绘制到 GLSurfaceView
*/
public class HandleTextureByOpenGLCameraActivity extends AppCompatActivity
implements GLSurfaceView.Renderer {
private Camera mCamera;
private GLSurfaceView mGLSurfaceView;
private SurfaceTexture mSurfaceTexture;
private DirectDrawer mDrawer;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
initGLSurfaceView();
setContentView(mGLSurfaceView);
}
@Override
protected void onDestroy() {
super.onDestroy();
mCamera.stopPreview();
mCamera.release();
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
int textureId = createTexture();
mDrawer = new DirectDrawer(textureId);
mSurfaceTexture = new SurfaceTexture(textureId);
mSurfaceTexture.setOnFrameAvailableListener(new SurfaceTexture.OnFrameAvailableListener() {
@Override
public void onFrameAvailable(SurfaceTexture surfaceTexture) {
mGLSurfaceView.requestRender();
}
});
mCamera = Camera.open();
try {
mCamera.setPreviewTexture(mSurfaceTexture);
mCamera.startPreview();
} catch (IOException ioe) {
// Something bad happened
}
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
}
@Override
public void onDrawFrame(GL10 gl) {
mSurfaceTexture.updateTexImage();
mDrawer.draw();
}
private void initGLSurfaceView() {
mGLSurfaceView = new GLSurfaceView(this);
mGLSurfaceView.setEGLContextClientVersion(2);
mGLSurfaceView.setEGLConfigChooser(8, 8, 8, 8, 16, 0);
mGLSurfaceView.getHolder().setFormat(PixelFormat.RGBA_8888);
mGLSurfaceView.setRenderer(this);
mGLSurfaceView.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
mGLSurfaceView.requestRender();
}
private int createTexture() {
int[] texture = new int[1];
GLES20.glGenTextures(1, texture, 0);
GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, texture[0]);
GLES20.glTexParameterf(GLES11Ext.GL_TEXTURE_EXTERNAL_OES,
GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_LINEAR);
GLES20.glTexParameterf(GLES11Ext.GL_TEXTURE_EXTERNAL_OES,
GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
GLES20.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES,
GL10.GL_TEXTURE_WRAP_S, GL10.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES,
GL10.GL_TEXTURE_WRAP_T, GL10.GL_CLAMP_TO_EDGE);
return texture[0];
}
/**
* 参考 VideoDumpView.java，注意这里用的是外部纹理 samplerExternalOES
*/
private static 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 : require\n" +
"precision mediump float;" +
"varying vec2 textureCoordinate;\n" +
"uniform samplerExternalOES s_texture;\n" +
"void main() {" +
" gl_FragColor = texture2D( s_texture, textureCoordinate );\n" +
"}";
private FloatBuffer vertexBuffer;
private FloatBuffer textureVerticesBuffer;
private ShortBuffer drawListBuffer;
private final int mProgram;
private int mPositionHandle;
private int mTextureCoordHandle;
private short drawOrder[] = {0, 1, 2, 0, 2, 3};
private static final int COORDS_PER_VERTEX = 2;
private final int vertexStride = COORDS_PER_VERTEX * 4; // 4 bytes per vertex
static float squareCoords[] = {
-1.0f, 1.0f,
-1.0f, -1.0f,
1.0f, -1.0f,
1.0f, 1.0f,
};
static float textureVertices[] = {
0.0f, 1.0f,
1.0f, 1.0f,
1.0f, 0.0f,
0.0f, 0.0f,
};
private int texture;
public DirectDrawer(int texture) {
this.texture = texture;
//顶点坐标
ByteBuffer bb = ByteBuffer.allocateDirect(squareCoords.length * 4);
bb.order(ByteOrder.nativeOrder());
vertexBuffer = bb.asFloatBuffer();
vertexBuffer.put(squareCoords);
vertexBuffer.position(0);
//顶点绘制顺序
ByteBuffer dlb = ByteBuffer.allocateDirect(drawOrder.length * 2);
dlb.order(ByteOrder.nativeOrder());
drawListBuffer = dlb.asShortBuffer();
drawListBuffer.put(drawOrder);
drawListBuffer.position(0);
//纹理坐标
ByteBuffer bb2 = ByteBuffer.allocateDirect(textureVertices.length * 4);
bb2.order(ByteOrder.nativeOrder());
textureVerticesBuffer = bb2.asFloatBuffer();
textureVerticesBuffer.put(textureVertices);
textureVerticesBuffer.position(0);
//编译着色器
int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
int fragmentShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderCode);
mProgram = GLES20.glCreateProgram();
GLES20.glAttachShader(mProgram, vertexShader);
GLES20.glAttachShader(mProgram, fragmentShader);
GLES20.glLinkProgram(mProgram);
}
public void draw() {
GLES20.glUseProgram(mProgram);
//使用纹理
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, texture);
//顶点位置
mPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");
GLES20.glEnableVertexAttribArray(mPositionHandle);
GLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, vertexStride, vertexBuffer);
//纹理坐标
mTextureCoordHandle = GLES20.glGetAttribLocation(mProgram, "inputTextureCoordinate");
GLES20.glEnableVertexAttribArray(mTextureCoordHandle);
GLES20.glVertexAttribPointer(mTextureCoordHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, vertexStride, textureVerticesBuffer);
//绘制
GLES20.glDrawElements(GLES20.GL_TRIANGLES, drawOrder.length, GLES20.GL_UNSIGNED_SHORT, drawListBuffer);
//结束
GLES20.glDisableVertexAttribArray(mPositionHandle);
GLES20.glDisableVertexAttribArray(mTextureCoordHandle);
}
//编译着色器
private int loadShader(int type, String shaderCode) {
int shader = GLES20.glCreateShader(type);
GLES20.glShaderSource(shader, shaderCode);
GLES20.glCompileShader(shader);
return shader;
}
}
}
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