bool Shader::compile()
{
assert(mId > 0 && "id is null so the shader source should be loaded first!");
glCompileShader(mId);
// check:
int compileStatus = GL_TRUE;
glGetShaderiv(mId, GL_COMPILE_STATUS, &compileStatus);
if (compileStatus == GL_FALSE)
{
LOG_ERROR("Compilation for %s shader failed!", mName.c_str());
logShaderInfo();
return false;
}
return true;
}
GLuint createProgram(const GLchar* vertexShaderSource[], const GLchar* fragmentShaderSource[])
{
// Generate program (empty here, will add shaders to it below)
GLuint programId = glCreateProgram();
// Create vertex shader
GLuint vertexShader = glCreateShader(GL_VERTEX_SHADER);
// Shaders are written in a C-like language called GLSL. Read more at: http://www.raywenderlich.com/3664/opengl-tutorial-for-ios-opengl-es-2-0
// Set vertex source
glShaderSource( vertexShader, 1, vertexShaderSource, NULL );
// Compile vertex source
glCompileShader( vertexShader );
// Check vertex shader for errors
GLint vShaderCompiled = GL_FALSE;
glGetShaderiv( vertexShader, GL_COMPILE_STATUS, &vShaderCompiled );
if( vShaderCompiled != GL_TRUE )
{
printf( "Failed to compile vertex shader %d!\n", vertexShader );
logShaderInfo( vertexShader );
return -1;
}
// Attach vertex shader to program
glAttachShader( programId, vertexShader );
// Create fragment shader
GLuint fragmentShader = glCreateShader( GL_FRAGMENT_SHADER );
// Set fragment source
glShaderSource( fragmentShader, 1, fragmentShaderSource, NULL );
// Compile fragment source
glCompileShader( fragmentShader );
// Check fragment shader for errors
GLint fShaderCompiled = GL_FALSE;
glGetShaderiv( fragmentShader, GL_COMPILE_STATUS, &fShaderCompiled );
if( fShaderCompiled != GL_TRUE )
{
printf( "Failed to compile fragment shader %d!\n", fragmentShader );
logShaderInfo( fragmentShader );
return -1;
}
// Attach fragment shader to program
glAttachShader(programId, fragmentShader);
// Link program
glLinkProgram( programId );
// Check for errors
GLint programSuccess = GL_TRUE;
glGetProgramiv(programId, GL_LINK_STATUS, &programSuccess);
if( programSuccess != GL_TRUE )
{
printf( "Error linking program %d!\n", programId );
logProgramInfo( programId );
return -1;
}
return programId;
}
