amadiosy / restir-vulkan

Vulkan implementation of ReSTIR

ReSTIR - Vulkan

CIS 565: GPU Programming and Architecture Final Project

• Xuanyi Zhou [GitHub] [LinkedIn]
• Xuecheng Sun [GitHub] [LinkedIn]
• Jiarui Yan [GitHub] [LinkedIn]

Project Goal

This is the final project for CIS 565: GPU Programming. The goal of the project is to implement ‘Spatiotemporal Reservoir Resampling for Real-Time Ray Tracing with Dynamic Direct Lighting’ or ReSTIR using Vulkan. It enables the usage of a large number of point and surface lights and the rendering of their shadows by combining various sampling techniques. Since the algorithm uses ray tracing for visibility testing, we explore using the Vulkan extension VK_KHR_ray_tracing for ray tracing. In addition, we also use Vulkan’s compute shader to implement a ray tracer, and compare the performance differences between the two methods. Besides, you can find a detailed proposal of this project here: Pitch Link.

Building the Project

0. Prerequisites on Windows:

   • Visual Studio 2019

   • The following packages:

     • GLFW3
     • Vulkan SDK
     • Dear ImGUI with glfw and Vulkan bindings

     These packages can be installed easily using vcpkg.

   • Nvidia Vulkan driver that supports the VK_KHR_ray_tracing extension. See https://developer.nvidia.com/vulkan-driver, section 'Khronos Vulkan Ray Tracing'.

   The code was written with portability in mind, but it has not been tested on other platforms.

1. Clone this repository with the --recurse-submodules flag.

2. Build the project using the standard CMake building process. The executable expects the compiled shaders to be located in shaders/, and while this is usually automatically guaranteed by the building process, in some configurations they may need to be manually copied.

Scenes

Specify GLTF scene files using the -scene flag. If the scene contains point lights that are used to simulate the effects of area lights, they can be ignored using -ignore_point_lights. If the scene doesn't contain any point lights or objects with emissive materials, a number of point lights will be randomly scattered in the scene. Currently this is hard-coded in sceneBuffers.h.

Here are some models provided by Nvidia converted to GLTF format. Some additional sample models can be found at https://github.com/KhronosGroup/glTF-Sample-Models.

Project Timeline

Milestone 1 (Nov. 18)

• GBuffer generation.
• Compute shader raytracing.
• Vulkan RT pipeline raytracing.
• GLTF scene loader.
• Reading the paper and understanding the algorithm.

MS1 Slides

Milestone 2 (Nov. 30)

• Baised ReSTIR Algorithm.
• Disney Principle BRDF Materials.

MS2 Slides

Milestone 3 (Dec. 7)

• Unbiased ReSTIR algorithm
• Experiments and data collection

MS3 Slides

References and Acknowledgments

• [1] Spatiotemporal Variance-Guided Filtering: Real-Time Reconstruction for Path-Traced Global Illumination
• [2] Dear ImGui
• [3] VulkanMemoryAllocator
• [4] tinygltf
• [5] MikkTSpace
• [6] MikkTSpace Houdini
• [7] FBX2glTF