c++ OpenGL显示YUV数据

#include <jni.h>
#include <GLES2/gl2.h>
#include <string.h>
#include "openglNative.h"
#include <android/log.h>
#include <EGL/egl.h>

#define LOG_TAG "OPENGL"
#define LOGI(...) __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,__VA_ARGS__)

GLuint program;
GLuint vertexShader;
GLuint pixelShader;
GLint _positionHandle = -1, _coordHandle = -1;

int _width = 0;
int _height = 0;

const GLchar *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";

const GLchar *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";

GLuint _frameBuffer;
GLuint _renderBuffer;

GLenum _textureI = GL_TEXTURE0;
GLenum _textureII = GL_TEXTURE1;
GLenum _textureIII = GL_TEXTURE2;
GLenum _tIindex = 0;
GLenum _tIIindex = 1;
GLenum _tIIIindex = 2;

GLint _yhandle = -1, _uhandle = -1, _vhandle = -1;
GLuint _ytid = 0, _utid = 0, _vtid = 0;

typedef struct {

    float position[3];
    float color[4];
    float texture[2];
} LLVertex;