OpenGL Programming Guide: The Official Guide to Learning OpenGL, Version 4.3, Eighth Edition

Tessellation Shaders

Up to this point, only vertex shaders have been available for us to manipulate geometric primitives. While there are numerous graphics techniques you can do using vertex shaders, they do have their limitations. One limitation is that they can’t create additional geometry during their execution. They really only update the data associated with the current vertex they are processing, and they can’t even access the data of other vertices in the primitives.

To address those issues, the OpenGL pipeline contains several other shader stages that address those limitations. In this chapter, we introduce tessellation shaders which, for example, can generate a mesh of triangles, using a new geometric primitive type called a patch. ...