GLSL Tutorial – Setup Example

The following source code contains all the steps described previously considering a program with three types of shaders: vertex, geometry, and fragment. The variable p, is assumed to be declared globally as GLuint.

void setShaders() {

	GLuint v, g, f;
	char *vs,*gs, *fs;

	// Create shader handlers
	v = glCreateShader(GL_VERTEX_SHADER);
	g = glCreateShader(GL_GEOMETRY_SHADER);
	f = glCreateShader(GL_FRAGMENT_SHADER);	

	// Read source code from files
	vs = textFileRead("example.vert");
	gs = textFileRead("example.geom");
	fs = textFileRead("example.frag");

	const char * vv = vs;
	const char * gg = gs;
	const char * ff = fs;

	// Set shader source
	glShaderSource(v, 1, &vv,NULL);
	glShaderSource(g, 1, &gg,NULL);
	glShaderSource(f, 1, &ff,NULL);

	free(vs);free(gs);free(fs);

	// Compile all shaders
	glCompileShader(v);
	glCompileShader(g);
	glCompileShader(f);

	// Create the program
	p = glCreateProgram();

	// Attach shaders to program
	glAttachShader(p,v);
	glAttachShader(p,g);
	glAttachShader(p,f);

	// Link and set program to use
	glLinkProgram(p);
	glUseProgram(p);
}