getProgramInfo.js

function getProgramInfo(gl, program) {
    var result = {
        attributes: [],
        uniforms: [],
        attributeCount: 0,
        uniformCount: 0
    },
        activeUniforms = gl.getProgramParameter(program, gl.ACTIVE_UNIFORMS),
        activeAttributes = gl.getProgramParameter(program, gl.ACTIVE_ATTRIBUTES);
    
    // Taken from the WebGl spec: 
    // http://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14
    var enums = {
        0x8B50: 'FLOAT_VEC2',
        0x8B51: 'FLOAT_VEC3',
        0x8B52: 'FLOAT_VEC4',
        0x8B53: 'INT_VEC2',
        0x8B54: 'INT_VEC3',
        0x8B55: 'INT_VEC4',
        0x8B56: 'BOOL',
        0x8B57: 'BOOL_VEC2',
        0x8B58: 'BOOL_VEC3',
        0x8B59: 'BOOL_VEC4',
        0x8B5A: 'FLOAT_MAT2',
        0x8B5B: 'FLOAT_MAT3',
        0x8B5C: 'FLOAT_MAT4',
        0x8B5E: 'SAMPLER_2D',
        0x8B60: 'SAMPLER_CUBE',
        0x1400: 'BYTE',
        0x1401: 'UNSIGNED_BYTE',
        0x1402: 'SHORT',
        0x1403: 'UNSIGNED_SHORT',
        0x1404: 'INT',
        0x1405: 'UNSIGNED_INT',
        0x1406: 'FLOAT'
    };
    
    // Loop through active uniforms
    for (var i=0; i < activeUniforms; i++) {
        var uniform = gl.getActiveUniform(program, i);
        uniform.typeName = enums[uniform.type];
        result.uniforms.push(uniform);
        result.uniformCount += uniform.size;
    }
    
    // Loop through active attributes
    for (var i=0; i < activeAttributes; i++) {
        var attribute = gl.getActiveAttrib(program, i);
        attribute.typeName = enums[attribute.type];
        result.attributes.push(attribute);
        result.attributeCount += attribute.size;
    }
    
    return result;
}