opengl es 2.0 视频播放
demo: https://github.com/wangzuxing/MyFFmpegH264H265YUVOpenGL
以YUV纹理贴图实现视频播放：
1、把jni端解码的YUV数据/摄像头预览的YUV数据传入glTexImage2D()函数，并以GL_LUMINANCE格式进行纹理加载、绑定
2、把YUV数据产生的相关纹理单元赋给片元着色器的各2D采样器，然后进行纹理采样、数值计算、转换成RGB数据
如下：
GLES20.glTexImage2D
(
GLES20.GL_TEXTURE_2D, //纹理单元的类型
0, //纹理单元的层次，非mipmap纹理level设置为0
GLES20.GL_LUMINANCE,
//纹理单元的数据格式：
// GL_RGB、GL_RGBA、GL_LUMINANCE、GL_LUMINANCE_ALPHA、GL_ALPHA
_video_width, //纹理单元的宽度
_video_height, //纹理单元的高度
0, //纹理单元的边框，如果包含边框取值为1，不包含边框取值为0
GLES20.GL_LUMINANCE, //data所指向的数据的格式
GLES20.GL_UNSIGNED_BYTE, //data所指向的数据的类型
y //指向的数据
);
GLES20Support.java:
public class GLES20Support {
public static boolean detectOpenGLES20(Context context) {
ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
ConfigurationInfo info = am.getDeviceConfigurationInfo(); // 获取配置信息, 取得GLES version
return (info.reqGlEsVersion >= 0x20000);
}
...
}MainActivity0.java：
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
if (GLES20Support.detectOpenGLES20(this) == false) { // 判断android系统是否支持opengl es 2.0
GLES20Support.getNoSupportGLES20Dialog(this);
}
GLFrameSurface glSurfaceView = new GLFrameSurface(this);
glSurfaceView.setEGLContextClientVersion(2); //设置OpenGL ES 2.0版本支持
glRenderer = new GLFrameRenderer(null, glSurfaceView, getDM(this));
glSurfaceView.setRenderer(glRenderer);
...
}
//1、主线程调用GLFrameRenderer glRenderer
//2、
boolean yuv_update = true;
Handler myHandler = new Handler() {
public void handleMessage(Message msg) {
switch (msg.what) {
...
case 1:
if(yuv_update){
glRenderer.update(width, height);
yuv_update = false;
}
byte[] y = new byte[yuvPlanes[0].remaining()];
yuvPlanes[0].get(y, 0, y.length);
byte[] u = new byte[yuvPlanes[1].remaining()];
yuvPlanes[1].get(u, 0, u.length);
byte[] v = new byte[yuvPlanes[2].remaining()];
yuvPlanes[2].get(v, 0, v.length);
glRenderer.update(y, u, v); //GLFrameRenderer glRenderer;
break;
...
}
super.handleMessage(msg);
}
};
// jni端需调用函数，传入解码的yuv数据到java端，由opengl es2.0进行纹理贴图显示
public void updateYUV(byte[] yuvData, int width0, int height0) {
synchronized (this) {
copyFrom(yuvData,width0,height0);
Message message = new Message();
message.what = 1;
myHandler.sendMessage(message);
}
}
public ByteBuffer[] yuvPlanes;
int planeSize;// = width * height;
int planeSize_l;
ByteBuffer[] planes = new ByteBuffer[3];
//析取出 Y、U、V 分量，送opengl es 2.0 的glTexImage2D()函数产生纹理数据
//GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_LUMINANCE, _video_width, _video_height, 0,GLES20.GL_LUMINANCE, GLES20.GL_UNSIGNED_BYTE, y); // y u v
public void copyFrom(byte[] yuvData, int width, int height) {
if (yuvPlanes == null) {
int[] yuvStrides = { width, width / 2, width / 2};
planeSize = width * height;
planeSize_l = planeSize*3/2;
yuvPlanes = new ByteBuffer[3];
yuvPlanes[0] = ByteBuffer.allocateDirect(yuvStrides[0] * height);
yuvPlanes[1] = ByteBuffer.allocateDirect(yuvStrides[1] * height / 2);
yuvPlanes[2] = ByteBuffer.allocateDirect(yuvStrides[2] * height / 2);
}
if (yuvData.length < planeSize_l) {
throw new RuntimeException("Wrong arrays size: " + yuvData.length);
}
planes[0] = ByteBuffer.wrap(yuvData, 0, planeSize);
planes[1] = ByteBuffer.wrap(yuvData, planeSize, planeSize / 4);
planes[2] = ByteBuffer.wrap(yuvData, planeSize + planeSize / 4, planeSize / 4);
for (int i = 0; i < 3; i++) {
yuvPlanes[i].position(0);
yuvPlanes[i].put(planes[i]);
yuvPlanes[i].position(0);
yuvPlanes[i].limit(yuvPlanes[i].capacity());
}
}
/*
packed formats：将Y、U、V值储存成Macro Pixels阵列，和RGB的存放方式类似。
planar formats：将Y、U、V的三个份量分别存放在不同的矩阵中。
COLOR_FormatYUV420Planar: YUV420P I420
COLOR_FormatYUV420SemiPlanar: YUV420SP NV12
YUV420P，Y，U，V三个分量都是平面格式，分为I420和YV12。I420格式和YV12格式的不同处在U平面和V平面的位置不同。
在I420格式中，U平面紧跟在Y平面之后，然后才是V平面（即：YUV）；但YV12则是相反（即：YVU）。
YUV420SP, Y分量平面格式，UV打包格式, 即NV12。 NV12与NV21类似，U 和 V 交错排列,不同在于UV顺序。
I420: YYYYYYYY UU VV =>YUV420P
YV12: YYYYYYYY VV UU =>YUV420P
NV12: YYYYYYYY UVUV =>YUV420SP
NV21: YYYYYYYY VUVU =>YUV420SP
*/
//yv12 =》 yuv420p ： yvu -> yuv
private void swapYV12toI420(byte[] yv12bytes, byte[] i420bytes, int width, int height)
{
System.arraycopy(yv12bytes, 0, i420bytes, 0,width*height);
System.arraycopy(yv12bytes, width*height+width*height/4, i420bytes, width*height,width*height/4);
System.arraycopy(yv12bytes, width*height, i420bytes, width*height+width*height/4,width*height/4);
}
// camera preview data --> onFrame() mediacodec编码
public void onFrame(byte[] buf, int offset, int length, int flag) {
swapYV12toI420(buf, h264, width, height); // I420 视频格式
if(isPlaying){
copyFrom(h264, width ,height); // h264 存放的就是I420格式的yuv数据
Message message = new Message(); // ui线程刷新显示
message.what = 1;
myHandler.sendMessage(message);
}
...
}
}GLFrameRenderer.java:
public class GLFrameRenderer implements Renderer {
private ISimplePlayer mParentAct;
private GLSurfaceView mTargetSurface;
private GLProgram prog = new GLProgram(0); // 顶点坐标、纹理坐标定义，vertex shader、fragment shader定义、读取，参数的传递、纹理的创建等
private int mScreenWidth, mScreenHeight;
private int mVideoWidth, mVideoHeight;
private ByteBuffer y;
private ByteBuffer u;
private ByteBuffer v;
public GLFrameRenderer(ISimplePlayer callback, GLSurfaceView surface, DisplayMetrics dm) {
mParentAct = callback;
mTargetSurface = surface;
mScreenWidth = 320;//dm.widthPixels;
mScreenHeight = 240;//dm.heightPixels;
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
if (!prog.isProgramBuilt()) {
prog.buildProgram(); // 2、读取vertex shader、fragment shader, createProgram(VERTEX_SHADER, FRAGMENT_SHADER);
// get handle for "vPosition" and "a_texCoord"
// get uniform location for y/u/v
}
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
GLES20.glViewport(0, 0, width, height);
}
@Override
public void onDrawFrame(GL10 gl) {
synchronized (this) {
if (y != null) {
// reset position, have to be done
y.position(0);
u.position(0);
v.position(0);
prog.buildTextures(y, u, v, mVideoWidth, mVideoHeight); //3、根据I420的y、u、v数据，产生对应的纹理贴图
GLES20.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
prog.drawFrame(); // 4、GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4); 渲染\显示纹理贴图
}
}
}
public void update(int w, int h) {
Utils.LOGD("update INIT E");
if (w > 0 && h > 0) {
if (mScreenWidth > 0 && mScreenHeight > 0) {
float f1 = 1f * mScreenHeight / mScreenWidth;
float f2 = 1f * h / w;
//1、根据视频高、宽比与屏幕高、宽比的比较，调用createBuffers(), 产生vertices buffer，四顶点
if (f1 == f2) {
prog.createBuffers(GLProgram.squareVertices);
} else if (f1 < f2) {
float widScale = f1 / f2;
prog.createBuffers(new float[] { -widScale, -1.0f, widScale, -1.0f, -widScale, 1.0f, widScale, 1.0f,});
} else {
float heightScale = f2 / f1;
prog.createBuffers(new float[] { -1.0f, -heightScale, 1.0f, -heightScale, -1.0f, heightScale, 1.0f, heightScale, });
}
}
if (w != mVideoWidth && h != mVideoHeight) {
this.mVideoWidth = w;
this.mVideoHeight = h;
int yarraySize = w * h;
int uvarraySize = yarraySize / 4;
synchronized (this) {
y = ByteBuffer.allocate(yarraySize);
u = ByteBuffer.allocate(uvarraySize);
v = ByteBuffer.allocate(uvarraySize);
}
}
}
}
public void update(byte[] ydata, byte[] udata, byte[] vdata) {
synchronized (this) {
y.clear();
u.clear();
v.clear();
y.put(ydata, 0, ydata.length);
u.put(udata, 0, udata.length);
v.put(vdata, 0, vdata.length);
// request to render
mTargetSurface.requestRender(); //5、GLSurfaceView请求渲染
}
}
}GLProgram.java
public class GLProgram {
// program id
private int _program;
// window position
public final int mWinPosition;
// texture id
private int _textureI;
private int _textureII;
private int _textureIII;
// texture index in gles
private int _tIindex;
private int _tIIindex;
private int _tIIIindex;
// vertices on screen
private float[] _vertices;
// handles
private int _positionHandle = -1, _coordHandle = -1;
private int _yhandle = -1, _uhandle = -1, _vhandle = -1;
private int _ytid = -1, _utid = -1, _vtid = -1;
// vertices buffer
private ByteBuffer _vertice_buffer;
private ByteBuffer _coord_buffer;
// video width and height
private int _video_width = -1;
private int _video_height = -1;
// flow control
private boolean isProgBuilt = false;
public GLProgram(int position) {
if (position < 0 || position > 4) {
throw new RuntimeException("Index can only be 0 to 4");
}
mWinPosition = position;
setup(mWinPosition);
}
public void setup(int position) {
switch (mWinPosition) {
case 1:
_vertices = squareVertices1; //
_textureI = GLES20.GL_TEXTURE0;
_textureII = GLES20.GL_TEXTURE1;
_textureIII = GLES20.GL_TEXTURE2;
_tIindex = 0; // GLES20.GL_TEXTURE0 纹理单元在系统中的索引为0，即opengl es 2.0函数中对参数为GLES20.GL_TEXTURE0的，也可以用0代替
_tIIindex = 1;
_tIIIindex = 2;
break;
case 2:
_vertices = squareVertices2;
_textureI = GLES20.GL_TEXTURE3;
_textureII = GLES20.GL_TEXTURE4;
_textureIII = GLES20.GL_TEXTURE5;
_tIindex = 3;
_tIIindex = 4;
_tIIIindex = 5;
break;
case 3:
_vertices = squareVertices3;
_textureI = GLES20.GL_TEXTURE6;
_textureII = GLES20.GL_TEXTURE7;
_textureIII = GLES20.GL_TEXTURE8;
_tIindex = 6;
_tIIindex = 7;
_tIIIindex = 8;
break;
case 4:
_vertices = squareVertices4;
_textureI = GLES20.GL_TEXTURE9;
_textureII = GLES20.GL_TEXTURE10;
_textureIII = GLES20.GL_TEXTURE11;
_tIindex = 9;
_tIIindex = 10;
_tIIIindex = 11;
break;
case 0:
default:
_vertices = squareVertices;
_textureI = GLES20.GL_TEXTURE0;
_textureII = GLES20.GL_TEXTURE1;
_textureIII = GLES20.GL_TEXTURE2;
_tIindex = 0;
_tIIindex = 1;
_tIIIindex = 2;
break;
}
}
public boolean isProgramBuilt() {
return isProgBuilt;
}
public void buildProgram() {
// TODO createBuffers(_vertices, coordVertices);
if (_program <= 0) {
_program = createProgram(VERTEX_SHADER, FRAGMENT_SHADER);
}
Utils.LOGD("_program = " + _program);
//get handle for "vPosition" and "a_texCoord"
//获取程序中顶点坐标属性引用（句柄）
_positionHandle = GLES20.glGetAttribLocation(_program, "vPosition");
Utils.LOGD("_positionHandle = " + _positionHandle);
checkGlError("glGetAttribLocation vPosition");
if (_positionHandle == -1) {
throw new RuntimeException("Could not get attribute location for vPosition");
}
//获取程序中顶点纹理坐标属性引用（句柄）
_coordHandle = GLES20.glGetAttribLocation(_program, "a_texCoord");
Utils.LOGD("_coordHandle = " + _coordHandle);
checkGlError("glGetAttribLocation a_texCoord");
if (_coordHandle == -1) {
throw new RuntimeException("Could not get attribute location for a_texCoord");
}
// get uniform location for y/u/v, we pass data through these uniforms
//获取程序中2D采样器引用（句柄），纹理贴图
_yhandle = GLES20.glGetUniformLocation(_program, "tex_y"); //
Utils.LOGD("_yhandle = " + _yhandle);
checkGlError("glGetUniformLocation tex_y");
if (_yhandle == -1) {
throw new RuntimeException("Could not get uniform location for tex_y");
}
_uhandle = GLES20.glGetUniformLocation(_program, "tex_u");
Utils.LOGD("_uhandle = " + _uhandle);
checkGlError("glGetUniformLocation tex_u");
if (_uhandle == -1) {
throw new RuntimeException("Could not get uniform location for tex_u");
}
_vhandle = GLES20.glGetUniformLocation(_program, "tex_v");
Utils.LOGD("_vhandle = " + _vhandle);
checkGlError("glGetUniformLocation tex_v");
if (_vhandle == -1) {
throw new RuntimeException("Could not get uniform location for tex_v");
}
isProgBuilt = true;
}
//build a set of textures, one for R, one for G, and one for B.
public void buildTextures(Buffer y, Buffer u, Buffer v, int width, int height) {
boolean videoSizeChanged = (width != _video_width || height != _video_height);
if (videoSizeChanged) {
_video_width = width;
_video_height = height;
Utils.LOGD("buildTextures videoSizeChanged: w=" + _video_width + " h=" + _video_height);
}
// building texture for Y data
if (_ytid < 0 || videoSizeChanged) {
if (_ytid >= 0) {
Utils.LOGD("glDeleteTextures Y");
GLES20.glDeleteTextures(1, new int[] { _ytid }, 0);
checkGlError("glDeleteTextures");
}
// GLES20.glPixelStorei(GLES20.GL_UNPACK_ALIGNMENT, 1);
//生成纹理ID
int[] textures = new int[1];
GLES20.glGenTextures
(
1, //产生的纹理id的数量
textures, //纹理id的数组
0 //偏移量
);
checkGlError("glGenTextures");
_ytid = textures[0];
Utils.LOGD("glGenTextures Y = " + _ytid);
}
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _ytid);
checkGlError("glBindTexture");
//实际加载纹理
GLES20.glTexImage2D
(
GLES20.GL_TEXTURE_2D, //纹理单元的类型
0, //纹理单元的层次，非mipmap纹理level设置为0
GLES20.GL_LUMINANCE, //纹理单元的数据格式 GL_RGB、GL_RGBA、GL_LUMINANCE、GL_LUMINANCE_ALPHA、GL_ALPHA
_video_width, //纹理单元的宽度
_video_height, //纹理单元的高度
0, //纹理单元的边框，如果包含边框取值为1，不包含边框取值为0
GLES20.GL_LUMINANCE, //data所指向的数据的格式
GLES20.GL_UNSIGNED_BYTE, //data所指向的数据的类型
y //指向的数据
);
checkGlError("glTexImage2D");
//非Mipmap纹理采样过滤参数
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);
//ST方向纹理拉伸方式
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);
// building texture for U data
if (_utid < 0 || videoSizeChanged) {
if (_utid >= 0) {
Utils.LOGD("glDeleteTextures U");
GLES20.glDeleteTextures(1, new int[] { _utid }, 0);
checkGlError("glDeleteTextures");
}
int[] textures = new int[1];
GLES20.glGenTextures(1, textures, 0);
checkGlError("glGenTextures");
_utid = textures[0];
Utils.LOGD("glGenTextures U = " + _utid);
}
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _utid);
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_LUMINANCE, _video_width / 2, _video_height / 2, 0,
GLES20.GL_LUMINANCE, GLES20.GL_UNSIGNED_BYTE, u);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, 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);
// building texture for V data
if (_vtid < 0 || videoSizeChanged) {
if (_vtid >= 0) {
Utils.LOGD("glDeleteTextures V");
GLES20.glDeleteTextures(1, new int[] { _vtid }, 0);
checkGlError("glDeleteTextures");
}
int[] textures = new int[1];
GLES20.glGenTextures(1, textures, 0);
checkGlError("glGenTextures");
_vtid = textures[0];
Utils.LOGD("glGenTextures V = " + _vtid);
}
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _vtid);
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_LUMINANCE, _video_width / 2, _video_height / 2, 0,
GLES20.GL_LUMINANCE, GLES20.GL_UNSIGNED_BYTE, v);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, 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);
}
//render the frame the YUV data will be converted to RGB by shader.
public void drawFrame() {
GLES20.glUseProgram(_program);
checkGlError("glUseProgram");
//指定顶点属性数组
GLES20.glVertexAttribPointer(_positionHandle, 2, GLES20.GL_FLOAT, false, 8, _vertice_buffer);
//指定渲染时索引值为_positionHandle的顶点属性数组的数据格式和位置, 顶点数据和shader程序中的变量进行关联
checkGlError("glVertexAttribPointer mPositionHandle");
GLES20.glEnableVertexAttribArray(_positionHandle); //使能索引值为_positionHandle的顶点属性数组
GLES20.glVertexAttribPointer(_coordHandle, 2, GLES20.GL_FLOAT, false, 8, _coord_buffer);
checkGlError("glVertexAttribPointer maTextureHandle");
GLES20.glEnableVertexAttribArray(_coordHandle);
// bind textures
GLES20.glActiveTexture(_textureI); //激活纹理单元
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _ytid); //绑定纹理对象到纹理单元
GLES20.glUniform1i(_yhandle, _tIindex); //通过_yhandle句柄，把该纹理单元赋值给shader中sampler2D tex_y
//GLES20.GL_TEXTURE0～GLES20.GL_TEXTURE31 纹理单元在系统中的索引为0～31，即opengl es 2.0函数中对参数为GLES20.GL_TEXTUREi，也可以用i代替（i=0~31）
GLES20.glActiveTexture(_textureII);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _utid);
GLES20.glUniform1i(_uhandle, _tIIindex);
GLES20.glActiveTexture(_textureIII);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _vtid);
GLES20.glUniform1i(_vhandle, _tIIIindex);
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4); // GL_TRIANGLE_STRIP绘制方式，数组中顶点的数量4
GLES20.glFinish();
GLES20.glDisableVertexAttribArray(_positionHandle); //禁用索引值为_positionHandle的顶点属性数组
GLES20.glDisableVertexAttribArray(_coordHandle);
}
/**
* create program and load shaders, fragment shader is very important.
*/
public int createProgram(String vertexSource, String fragmentSource) {
// create shaders
int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource); //加载顶点着色器
int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource); //加载片元着色器
// just check
Utils.LOGD("vertexShader = " + vertexShader);
Utils.LOGD("pixelShader = " + pixelShader);
int program = GLES20.glCreateProgram(); //创建程序
if (program != 0) {
GLES20.glAttachShader(program, vertexShader); //向程序中加入顶点着色器
checkGlError("glAttachShader");
GLES20.glAttachShader(program, pixelShader); //向程序中加入片元着色器
checkGlError("glAttachShader");
GLES20.glLinkProgram(program); //链接程序
int[] linkStatus = new int[1]; //存放链接成功program数量的数组
GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0); //获取program的链接情况
if (linkStatus[0] != GLES20.GL_TRUE) {
Utils.LOGE("Could not link program: ");
Utils.LOGE(GLES20.glGetProgramInfoLog(program));
GLES20.glDeleteProgram(program);
program = 0;
}
}
return program;
}
/**
* create shader with given source.
*/
private int loadShader(int shaderType, String source) {
int shader = GLES20.glCreateShader(shaderType); //根据类型创建shader
if (shader != 0) {
GLES20.glShaderSource(shader, source); //加载shader的源代码
GLES20.glCompileShader(shader); //编译shader
int[] compiled = new int[1]; //存放编译成功shader数量的数组
GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0); //获取Shader的编译情况
if (compiled[0] == 0) {
Utils.LOGE("Could not compile shader " + shaderType);
Utils.LOGE(GLES20.glGetShaderInfoLog(shader));
GLES20.glDeleteShader(shader);
shader = 0;
}
}
return shader;
}
/**
* these two buffers are used for holding vertices, screen vertices and texture vertices.
*/
void createBuffers(float[] vert) {
_vertice_buffer = ByteBuffer.allocateDirect(vert.length * 4); // 创建顶点坐标数据缓冲
_vertice_buffer.order(ByteOrder.nativeOrder());
_vertice_buffer.asFloatBuffer().put(vert);
_vertice_buffer.position(0);
if (_coord_buffer == null) {
_coord_buffer = ByteBuffer.allocateDirect(coordVertices.length * 4); // 根据纹理坐标数组---创建顶点纹理坐标数据缓冲
_coord_buffer.order(ByteOrder.nativeOrder()); //设置本地字节序
_coord_buffer.asFloatBuffer().put(coordVertices); //转换为Float型缓冲，并向缓冲区中放入顶点纹理数据
_coord_buffer.position(0); //设置缓冲区起始位置
}
}
private void checkGlError(String op) {
int error;
while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
Utils.LOGE("***** " + op + ": glError " + error);
throw new RuntimeException(op + ": glError " + error);
}
}
//默认定义的屏幕顶点坐标
static float[] squareVertices = { -1.0f, -1.0f, 1.0f, -1.0f, -1.0f, 1.0f, 1.0f, 1.0f, }; // fullscreen
static float[] squareVertices1 = { -1.0f, 0.0f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, 1.0f, }; // left-top
static float[] squareVertices2 = { 0.0f, -1.0f, 1.0f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, }; // right-bottom
static float[] squareVertices3 = { -1.0f, -1.0f, 0.0f, -1.0f, -1.0f, 0.0f, 0.0f, 0.0f, }; // left-bottom
static float[] squareVertices4 = { 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, }; // right-top
//顶点纹理坐标
private static float[] coordVertices = { 0.0f, 1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, };// whole-texture
//顶点着色器代码 vec4 vPosition齐次坐标(x,y,0,1)
private static final String VERTEX_SHADER = "attribute vec4 vPosition;\n" + "attribute vec2 a_texCoord;\n"
+ "varying vec2 tc;\n" + "void main() {\n" + "gl_Position = vPosition;\n" + "tc = a_texCoord;\n" + "}\n";
//片元着色器代码， sampler2D对应GL_TEXTURE_2D的纹理采样器
private static final String FRAGMENT_SHADER = "precision mediump float;\n" + "uniform sampler2D tex_y;\n"
+ "uniform sampler2D tex_u;\n" + "uniform sampler2D tex_v;\n" + "varying vec2 tc;\n" + "void main() {\n"
+ "vec4 c = vec4((texture2D(tex_y, tc).r - 16./255.) * 1.164);\n"
+ "vec4 U = vec4(texture2D(tex_u, tc).r - 128./255.);\n"
+ "vec4 V = vec4(texture2D(tex_v, tc).r - 128./255.);\n" + "c += V * vec4(1.596, -0.813, 0, 0);\n"
+ "c += U * vec4(0, -0.392, 2.017, 0);\n" + "c.a = 1.0;\n" + "gl_FragColor = c;\n" + "}\n";
}
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