Questions:
    what type of info is contained in uniforms (global data)?
        modelview
        projection
        clipping planes
        texture map (image)
        light source
    what steps would the Painter's Algorithm be in?
        CPU
    The order of the stages is ...
    where would lighting be?
        gouraud shading = vertex shader (normal in, color out)
        phong shading = fragment shader (normal in, color out)
    what is varying per vertex?
        screen position (required)
        world position, normal
        texture coordinate
        color
        (maybe: distance from clipping plane)