Cull before vertex attribute fetch and vertex lighting

Abstract

One embodiment of the invention sets forth a mechanism for compiling a vertex shader program into two portions, a culling portion and a shading portion. The culling portion of the compiled vertex shader program specifies vertex attributes and instructions of the vertex shader program needed to determine whether early vertex culling operations should be performed on a batch of vertices associated with one or more primitives of a graphics scene. The shading portion of the compiled vertex shader program specifies the remaining vertex attributes and instructions of the vertex shader program for performing vertex lighting and performing other operations on the vertices in the batch of vertices. When the compiled vertex shader program is executed by graphics processing hardware, the shading portion of the compiled vertex shader is executed only when early vertex culling operations are not performed on the batch of vertices.