Adding Features to Your Game - Learn HTML5 by Creating Fun Games - page 269

// Step 1: Create a shader program
var program = gl.createProgram();
// Step 2: Attach both shaders into the
program
gl.attachShader(program, shaderFrag);
gl.attachShader(program, shaderVert);
// Step 3: Link the program
gl.linkProgram(program);
return program;
}
(function main() {
// ...
var shaderFrag = getShader(gl,
document.getElementById("glsl-frag-simple").textContent,
gl.FRAGMENT_SHADER);
var shaderVert = getShader(gl,
document.getElementById("glsl-vert-simple").textContent,
gl.VERTEX_SHADER);
var shader = getShaderProgram(gl, shaderFrag,
shaderVert);
// Specify which shader program is to be used
gl.useProgram(shader);
// Allocate space in GPU for variables
shader.attribVertPos =
gl.getAttribLocation(shader, "aVertPos");