Polymer is a modern OpenGL renderer written by Plagman utilizing modern shaders and demanding a lot of CPU/GPU power for high performance. Polymer supports modern diffuse/normal/parallax/specular/height mapping and dynamic lighting.
Polymer supersedes Polymost.
Screenshots can be found at the EDuke32 homepage.
Polymer's source code can be found under the BUILD license here: http://svn.eduke32.com/eduke32/polymer/eduke32/build/