The VisTest? system responsible for culling was optimized with more cache friendly algorithms.
24.1.2009 SSE Matrices
For optimization purposes all key matrix operations are now sped up via SSE instruction useage.
4.1.2009 Material shdcontrol
Similar to the texcontrol, one can now exchange a material's shader at runtime. This only works under certain conditions (shaders must have same parameter setup), however errors will be generated if the passed shader isn't compatible.
The tiletexture based terrain is being revised. Now supports custom materials, proper instances of a l3dtbterrain, whose position influences the visible rectangle. This allows much more control and multiple l3dtbterrains from the same tbterrain with different sizes. The terraindecals got individual sortids.
rendersystem.swapinterval sometimes wasnt set properly and not memorized.
gpu vendor detection, introduced in early 1.x build, resulted into non optimal default settings and slower performance.