Meshlet lab
The mesh is cut into small clusters (each colour is one meshlet). The GPU tests each cluster's bounding sphere and normal cone, and skips whole clusters that face away or sit off-screen — before any triangle is processed.
Meshlets
40
Culled by cone
15
Culled by frustum
0
Triangles sent
1440 / 2304
Work removed
38%
Tests paid
40 cluster tests
Try: small meshlets (8) cull more precisely but cost many more tests; huge ones (256) have wide cones that almost never cull. Around 64–128 triangles is a common choice, not a hardware rule.