Imprimis is a fork of Tesseract, which is a fork of the Cube 2: Sauerbraten engine. The goal of the Imprimis engine is to provide a clean, documented and consistent base with which to build first person shooter games on.

No more long calclight pauses... just plop down the light, move it, change its color, or do whatever else with it. It all happens in real-time now.

Like Tesseract, Imprimis removes the static lightmapping system of Sauerbraten and replaces it with completely dynamic lighting system based on deferred shading and shadowmapping.

Imprimis' Tesseract base provides a bunch of new rendering features such as:

deferred shading
omnidirectional point lights using cubemap shadowmaps
perspective projection spotlight shadowmaps
orthographic projection sunlight using cascaded shadowmaps
HDR rendering with tonemapping and bloom
real-time diffuse global illumination for sunlight (radiance hints)
volumetric lighting
screen-space ambient occlusion
screen-space reflections and refractions for water and glass (use as many water planes as you want now!)
screen-space refractive alpha cubes
deferred MSAA, subpixel morphological anti-aliasing (SMAA 1x, T2x, S2x, and 4x), FXAA, and temporal AA
runs on both OpenGL Core (3.0+) and legacy (2.0+) contexts

For documentation on the engine, see doc/engine.md.