Programs that create bottlenecks in the geometry (per-polygon) stage are termed transform limited. To test for bottlenecks in geometry operations, change the program so that the application code runs at the same speed and the same number of pixels are filled, but the geometry work is reduced. For example, if you are using lighting, call glDisable() with a GL_LIGHTING argument to temporarily turn off lighting. If performance improves, your application has a per-polygon bottleneck. For more information, see ``Tuning the Geometry Subsystem''.