As Shader Model 3.0 becomes more and more popular, we decided to overhaul our Standard Material to support an optimised lighting scheme for Shader Model 3.0.

In Shader model 2.0 and below, it is still quite possible to run out of instructions causing the shader not to render. Therefor, multiple lights are often done as seperate passes to prevent running out of instructions (each pass can access a certain number of instructions). However rendering 'multiple passes' (one for each light) essentially means rendering the model multiple times.

With the newly optimised Standard Material, artists can now choose to render all lights in a single pass.