You can download the version 0.7 of this demo for free here :

https://drive.google.com/file/d/1uIoiH5F4Fux1k2O3V67RFMc05CMNPMId/view?usp=sharing

The light is fully dynamic, sky light and global illumination are ray traced, and you can move the sun with the mouse buttons.

This demo features :
- High quality assets
- High resolution textures (4K - 8K)
- Dynamic time of day
- Every lighting feature is ray traced
- An UI allowing you to play with the lighting settings and features

Note : A very powerful GPU is required, RTX recommended.

Global Illumination has been one of the key to realistic CG, and ray tracing is the most accurate technique there is. For years the movie industry has been using and optimizing ray tracing to create the most accurate and realistic renders, but with very long render times. Indeed RTGI is very demanding, some renders take multiple hours (or dozens) for an image to render.
Fast forward today, ray tracing GI is possible in real time, thanks to the recent GPUs and the amazing work of thousands of engineers around the world.
This is to me very impressive, since I’ve been following its development for a decade now.
Petra RTGI is a small personal project to showcase how good this tech is on recent hardware, but also how performance heavy it is.
It’s still the early days of real time ray tracing, and I can’t wait to see games using it for light computation in the future. It will probably take 5+ years for RTGI to be used broadly, but you can test it now with this demo.

With the current distributed hardware, optimized methods like SVOGI and Lumen are necessary for good performance, and can offer very high quality results.

Here’s a small article I wrote about Lumen : https://simonmajar.com/blog/mNG8/the-need-for-lumen