knightcrawler25 / optix-pathtracer

Simple physically based path tracer based on Nvidia's Optix Ray Tracing Engine

OptixPathTracer

Dining Room

⚠️ Warning

Code in this repo was written for an older version of OptiX (5.x) and the repo is not maintained anymore. I would recommend using the newer OptiX 7.x API. Have a look at the following repos:

https://github.com/NVIDIA/OptiX_Apps
https://github.com/owl-project/owl
https://github.com/shocker-0x15/OptiX_Utility

If you're specifically looking for an implementation of the Disney BSDF then have a look at PBRT-v3 or my other repo

A physically based path tracer with support for Disney BRDF.

This was created by putting together bits and pieces from the Nvidia's Optix Advanced Samples Introduction tutorials. The feature set is very basic since this is just a learning excercise, so if you see horribly written code or things that can be done in a much better way please do share :)

Features

( Almost all were part of existing code from the Nvidia's Optix Advanced Samples Repository on Github )

• Unidirectional Path Tracing
• Disney BRDF
• Simple Glass BTDF
• Sphere and Rect lights
• Multiple Importance Sampling
• Mesh Loading
• Simple Scene File (Basically stolen from Miles Macklin's excellent Tinsel renderer ) so all credits go to him.

For the modified .obj files that go with the scene files, unzip the data.rar file in src/data/ into the same folder

Following are some scenes rendered with the path tracer

Bedroom

Spaceship (Render Time: ~6 minutes on a GTX 750ti)

Stormtrooper (Render Time: ~4 minutes)

Coffee Pot (Render Time: 4 minutes. 1k spp)

Remake of the Disney Hyperion Scene (Render Time: Quite long)

Thanks to Simon Kallweit for helping me out with the importance sampling code. He also has a nice write up of his implementation

Models are from Benedikt Bitterli's Rendering Resources.