ref: adb27023e44aa64b868881e0b9e11bbb6ea4cae9
dir: /ios/src/H264bsdRendererGl.m/
//
// YuvDataRenderer.m
// h264bsd
//
// Created by Sam Leitch on 2014-03-30.
// Copyright (c) 2014 h264bsd. All rights reserved.
//
#import "H264bsdRendererGl.h"
@interface H264bsdRendererGl ()
{
GLuint _programRef;
GLuint _positionRef;
GLuint _positionBufferRef;
GLuint _texcoordRef;
GLuint _texcoordBufferRef;
GLuint _samplerRef[3];
GLuint _textureRef[3];
}
@end
#define STRINGIZE(x) #x
#define STRINGIZE2(x) STRINGIZE(x)
#define SHADER_STRING(text) @ STRINGIZE2(text)
NSString *const vertexShaderString;
NSString *const fragmentShaderString;
static GLuint compileShader(GLenum type, NSString *shaderString);
static const GLfloat positionVertices[] = {
-1.0f, -1.0f,
1.0f, -1.0f,
-1.0f, 1.0f,
1.0f, 1.0f,
};
static const GLfloat texcoordVertices[] = {
0.0f, 1.0f,
1.0f, 1.0f,
0.0f, 0.0f,
1.0f, 0.0f,
};
@implementation H264bsdRendererGl
- (id)initWithContext:(EAGLContext *)context
{
self = [super init];
if(self)
{
_context = context;
if(![EAGLContext setCurrentContext:context]) {
NSLog(@"failed to setup context");
return nil;
}
[self initProgram];
[self initBuffers];
[self initTextures];
}
return self;
}
- (void)initProgram
{
GLuint vertexShader = compileShader(GL_VERTEX_SHADER, vertexShaderString);
if (!vertexShader) return;
GLuint fragmentShader = compileShader(GL_FRAGMENT_SHADER, fragmentShaderString);
if (!fragmentShader) return;
_programRef = glCreateProgram();
glAttachShader(_programRef, vertexShader);
glAttachShader(_programRef, fragmentShader);
glLinkProgram(_programRef);
GLint status;
glGetProgramiv(_programRef, GL_LINK_STATUS, &status);
if (status == GL_FALSE) {
NSLog(@"Failed to link program %d", _programRef);
return;
}
_positionRef = glGetAttribLocation(_programRef, "position");
_texcoordRef = glGetAttribLocation(_programRef, "texcoord_a");
_samplerRef[0] = glGetUniformLocation(_programRef, "ySampler");
_samplerRef[1] = glGetUniformLocation(_programRef, "uSampler");
_samplerRef[2] = glGetUniformLocation(_programRef, "vSampler");
}
- (void)initBuffers
{
glGenBuffers(1, &_positionBufferRef);
glBindBuffer(GL_ARRAY_BUFFER, _positionBufferRef);
glBufferData(GL_ARRAY_BUFFER, 2 * 4 * sizeof(float), positionVertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(_positionRef);
glVertexAttribPointer(_positionRef, 2, GL_FLOAT, GL_FALSE, 0, 0);
glGenBuffers(1, &_texcoordBufferRef);
glBindBuffer(GL_ARRAY_BUFFER, _texcoordBufferRef);
glBufferData(GL_ARRAY_BUFFER, 2 * 4 * sizeof(float), texcoordVertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(_texcoordRef);
glVertexAttribPointer(_texcoordRef, 2, GL_FLOAT, GL_FALSE, 0, 0);
}
- (void)initTextures
{
glGenTextures(3, _textureRef);
for(int i = 0; i < 3; ++i)
{
glActiveTexture(GL_TEXTURE0 + i);
glBindTexture(GL_TEXTURE_2D, _textureRef[i]);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
}
}
- (void)dealloc
{
if(![EAGLContext setCurrentContext:_context]) {
NSLog(@"failed to setup context");
return;
}
glDeleteProgram(_programRef);
glDeleteTextures(3, _textureRef);
glDeleteBuffers(1, &_positionBufferRef);
glDeleteBuffers(1, &_texcoordBufferRef);
}
- (void)renderNextOutputPictureWithDecoder:(H264bsdDecoder *)decoder
{
if(![EAGLContext setCurrentContext:self.context]) {
NSLog(@"failed to setup context");
return;
}
NSData *yuvData = [decoder nextOutputPicture];
if(!yuvData) return;
NSInteger width = decoder.outputWidth;
NSInteger height = decoder.outputHeight;
NSInteger uvWidth = width/2;
NSInteger uvHeight = height/2;
UInt8* yBuf = (UInt8*)yuvData.bytes;
UInt8* uBuf = yBuf + (width * height);
UInt8* vBuf = uBuf + (uvWidth * uvHeight);
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
glUseProgram(_programRef);
GLsizei textureWidth[] = { width, uvWidth, uvWidth };
GLsizei textureHeight[] = { height, uvHeight, uvHeight };
GLvoid* textureBuf[] = { yBuf, uBuf, vBuf };
for(int i = 0; i < 3; ++i)
{
glUniform1i(_samplerRef[i], i);
glActiveTexture(GL_TEXTURE0 + i);
glBindTexture(GL_TEXTURE_2D, _textureRef[i]);
glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, textureWidth[i], textureHeight[i], 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, textureBuf[i]);
}
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
bool glError = false;
GLenum glStatus = glGetError();
while (glStatus != GL_NO_ERROR) {
NSLog(@"GL error: %x", glStatus);
glError = true;
glStatus = glGetError();
}
}
@end
NSString *const vertexShaderString = SHADER_STRING
(
attribute vec4 position;
attribute vec4 texcoord_a;
varying vec2 texcoord;
void main()
{
gl_Position = position;
texcoord = texcoord_a.xy;
}
);
NSString *const fragmentShaderString = SHADER_STRING
(
varying highp vec2 texcoord;
uniform sampler2D ySampler;
uniform sampler2D uSampler;
uniform sampler2D vSampler;
const mediump mat4 yuv2rgb = mat4(1.1643828125, 0, 1.59602734375, -.87078515625,
1.1643828125, -.39176171875, -.81296875, .52959375,
1.1643828125, 2.017234375, 0, -1.081390625,
0, 0, 0, 1);
void main()
{
mediump vec4 yuv = vec4(0.0, 0.0, 0.0, 1.0);
yuv.r = texture2D(ySampler, texcoord).r;
yuv.g = texture2D(uSampler, texcoord).r;
yuv.b = texture2D(vSampler, texcoord).r;
mediump vec4 rgb = yuv * yuv2rgb;
gl_FragColor = rgb;
}
);
static GLuint compileShader(GLenum type, NSString *shaderString)
{
GLint status;
const GLchar *sources = (GLchar *)shaderString.UTF8String;
GLuint shader = glCreateShader(type);
if (shader == 0 || shader == GL_INVALID_ENUM) {
NSLog(@"Failed to create shader %d", type);
return 0;
}
glShaderSource(shader, 1, &sources, NULL);
glCompileShader(shader);
#ifdef DEBUG
GLint logLength;
glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &logLength);
if (logLength > 0)
{
GLchar *log = (GLchar *)malloc(logLength);
glGetShaderInfoLog(shader, logLength, &logLength, log);
NSLog(@"Shader compile log:\n%s", log);
free(log);
}
#endif
glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
if (status == GL_FALSE) {
glDeleteShader(shader);
NSLog(@"Failed to compile shader:\n");
return 0;
}
return shader;
}