1. A method for producing a shading procedure for real-time rendering of computer images, comprising the steps of: (1) receiving a shading function; (2) identifying in the shading function at least one candidate block of code for simplification; (3) generating, for each candidate block of code identified in step (2), at least one simplified block of code that can be substituted for the candidate block of code during image rendering; (4) associating each candidate block of code identified in step (2) and each simplified block of code generated in step (3) with at least one input parameter; (5) assembling each candidate block of code identified in step (2) and each simplified block of code generated in step (3) into a level of detail shading function, wherein the at least one input parameter is used to select at least one block of code that is to be used to shade an object during rendering of the object; and (6) storing the level of detail shading function in a computer readable medium.