Setup for GLSL – Example

The following source code contains all the steps described previously. The variables p,f,v are declared globally as (OpenGL 2.0 syntax) GLuint or (ARB extension syntax) GLhandleARB.

OpenGL 2.0 syntax:

void setShaders() {

	char *vs,*fs;

	v = glCreateShader(GL_VERTEX_SHADER);
	f = glCreateShader(GL_FRAGMENT_SHADER);	

	vs = textFileRead("toon.vert");
	fs = textFileRead("toon.frag");

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

	glShaderSource(v, 1, &vv,NULL);
	glShaderSource(f, 1, &ff,NULL);

	free(vs);free(fs);

	glCompileShader(v);
	glCompileShader(f);

	p = glCreateProgram();

	glAttachShader(p,v);
	glAttachShader(p,f);

	glLinkProgram(p);
	glUseProgram(p);
}

ARB extension syntax:

void setShaders() {

	char *vs,*fs;

	v = glCreateShaderObjectARB(GL_VERTEX_SHADER_ARB);
	f = glCreateShaderObjectARB(GL_FRAGMENT_SHADER_ARB);	

	vs = textFileRead("toon.vert");
	fs = textFileRead("toon.frag");

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

	glShaderSourceARB(v, 1, &vv,NULL);
	glShaderSourceARB(f, 1, &ff,NULL);

	free(vs);free(fs);

	glCompileShaderARB(v);
	glCompileShaderARB(f);

	p = glCreateProgramObjectARB();

	glAttachObjectARB(p,v);
	glAttachObjectARB(p,f);

	glLinkProgramARB(p);

	glUseProgramObjectARB(p);
}

A complete GLUT example is available:OpenGL 2.0 syntax and ARB extension syntax, containing two simple shaders, and the text file reading functions. A Unix version (ARB extension syntax only) can be obtained here thanks to Wojciech Milkowski. Please let him know if you use it: wmilkowski ‘at’ gazeta.pl