大神求助

- (GLuint)compileShader:(NSString*)shaderName withType:(GLenum)shaderType {
// 1
NSString* shaderPath = [[NSBundle mainBundle] pathForResource:shaderName
ofType:@" glsl"];
NSError* error;
NSString* shaderString = [NSString stringWithContentsOfFile:shaderPath
encoding:NSUTF8StringEncoding error:&error];
if (!shaderString) {
NSLog(@" Error loading shader: %@", error.localizedDescription);
exit(1);
}
// 2
GLuint shaderHandle = glCreateShader(shaderType);
// 3
constchar* shaderStringUTF8 = [shaderString UTF8String];
int shaderStringLength = [shaderString length];
glShaderSource(shaderHandle, 1, &shaderStringUTF8, &shaderStringLength);
// 4
glCompileShader(shaderHandle);
// 5
GLint compileSuccess;
glGetShaderiv(shaderHandle, GL_COMPILE_STATUS, &compileSuccess);
if (compileSuccess == GL_FALSE) {
GLchar messages[256];
glGetShaderInfoLog(shaderHandle, sizeof(messages), 0, &messages[0]);
NSString *messageString = [NSString stringWithUTF8String:messages];
NSLog(@" %@", messageString);
exit(1);
}
return shaderHandle;
}
- (void)compileShaders {
// 1
GLuint vertexShader = [self compileShader:@" SimpleVertex"
withType:GL_VERTEX_SHADER];
GLuint fragmentShader = [self compileShader:@" SimpleFragment"
withType:GL_FRAGMENT_SHADER];
// 2
GLuint programHandle = glCreateProgram();
glAttachShader(programHandle, vertexShader);
glAttachShader(programHandle, fragmentShader);
glLinkProgram(programHandle);
// 3
GLint linkSuccess;
glGetProgramiv(programHandle, GL_LINK_STATUS, &linkSuccess);
if (linkSuccess == GL_FALSE) {
GLchar messages[256];
glGetProgramInfoLog(programHandle, sizeof(messages), 0, &messages[0]);
NSString *messageString = [NSString stringWithUTF8String:messages];
NSLog(@" %@", messageString);
exit(1);
}
// 4
glUseProgram(programHandle);
// 5
_positionSlot = glGetAttribLocation(programHandle, "Position");
_colorSlot = glGetAttribLocation(programHandle, "SourceColor");
glEnableVertexAttribArray(_positionSlot);
glEnableVertexAttribArray(_colorSlot);
}
SimpleVertex.glsl //顶点着色器
attribute vec4 Position; // 1
attribute vec4 SourceColor; // 2
varying vec4 DestinationColor; // 3
void main(void) { // 4
DestinationColor = SourceColor; // 5
gl_Position = Position; // 6
}
SimpleFragment.glsl //片段着色器
varying lowp vec4 DestinationColor; // 1
void main(void) { // 2
gl_FragColor = DestinationColor; // 3
}
// 1
GLuint vertexShader = [self compileShader:@" SimpleVertex"
withType:GL_VERTEX_SHADER];
GLuint fragmentShader = [self compileShader:@" SimpleFragment"
withType:GL_FRAGMENT_SHADER];
为什么这段代码会出 error，小弟初学者，很多不懂的地方，请见谅，下边是报的错：
error:0:9: 'projection':syntax error syntax error
error:parser found no code to compile in source strings