The Primitive Count metric shows the number of rendering primitives assembled and put into the Input Assembly stage of the pipeline.
- If you render 100 points, the IA stage assembles 100 point primitives and the Primitive Count is 100.
- If you render two triangles as a triangle list, the IA stage assembles two triangles and the Primitive Count is two.
- If you render two triangles as a triangle strip, the IA assembles two triangles and the Primitive Count is two.
If geometry/vertex processing becomes a bottleneck, try to reduce number of primitives sent to GPU for each frame by:
- Simplifying your rendering geometry; for example, show small geometry details using bump maps instead of triangles, use lower detail models for far away objects, or use textures with multiple mipmaps.
- Optimizing your scene through various culling techniques; for example, use Binary Space Partitioning (BSP), Portal rendering, or Octrees.