alt Hacker NewsMicrocode was only used for the RSP, which was a modified MIPS coprocessor and could only realistically be used for T&L. After that, the RSP then sends triangles to the RDP for rasterization, pixel pipeline, and blending, all of which are fixed-function, admittedly with some somewhat flexible color combiner stuff.
I appreciate the correction. Still, programmable T&L was kind of a big deal. PC GPUs didn’t get hardware T&L until the DX7 era, and it didn’t really become programmable until DX9/Shader Model 2.0.