SEUS (Sonic Ether’s Unbelievable Shaders) is a shaderpack for Minecraft to be used with OptiFine or GLSL Shaders Mod (legacy).
SEUS PTGI is an experimental version of SEUS that includes a totally custom software implementation of ray tracing that does not require an RTX graphics card. The “PTGI” in the name stands for “Path Traced Global Illumination”, which is the main feature of this project. It also includes ray traced reflections.