meshlet

A meshlet is a small cluster of triangles that is used in modern graphics rendering pipelines, particularly in real-time applications like video games. The concept of mesh shading, which meshlets are a part of, aims to improve the efficiency of rendering large and complex geometric scenes. Instead of processing each individual triangle on the GPU, a group of triangles is collected into a meshlet. These meshlets are then typically processed in larger batches.

The GPU can then determine which meshlets are visible to the camera. If an entire meshlet is deemed outside the view frustum or too small to be rendered, the entire cluster of triangles within it can be culled (discarded) without needing to examine each individual triangle. This culling is much more efficient than traditional per-triangle culling. For visible meshlets, the GPU can then perform further culling of individual triangles or even draw the entire meshlet if it's sufficiently small.

Meshlets help address the bottleneck of vertex shading and primitive assembly in traditional rendering pipelines, especially when dealing with millions or billions of triangles. By grouping triangles, fewer draw calls are needed, and the overhead associated with processing small geometric primitives is reduced. This leads to higher frame rates and the ability to render more detailed environments. The exact size and composition of a meshlet can vary depending on the specific implementation and hardware.