This is a toy renderer written in C using Vulkan. It is intentionally minimalist. It has been developed and used for the papers "BRDF Importance Sampling for Polygonal Lights" and "BRDF Importance Sampling for Linear Lights." Correspondingly, there are two branches. For more information see: https://momentsingraphics.de/ToyRendererOverview.html
Downloading Data
Scenes and other data that are needed to run the renderer are available on the websites for the papers: http://momentsingraphics.de/Siggraph2021.html http://momentsingraphics.de/HPG2021.html
Building the Renderer
The renderer is written in C99 with few dependencies. Imgui and GLFW are specified as submodules, so you should be able to clone them alongside this repository (use git clone --recurse-submodules). You also need the latest Vulkan SDK (version 1.2.176.1 or later) available here: https://vulkan.lunarg.com/sdk/home
On Linux the Vulkan SDK should be available via your package manager. Validation layers are needed for a debug build but not for a release build. You may have to use beta drivers, depending on what your package repositories provide otherwise. https://developer.nvidia.com/vulkan-driver
Vulkan on macOS is notoriously problematic but it may work with the latest SDK.
Once all dependencies are available, use CMake to create project files and build.
Running the Renderer
Get data files first (see above). Run the binary with current working directory vulkan_renderer.
Ray tracing uses the extension VK_KHR_ray_query. The latest NVIDIA drivers for Windows support it: https://www.nvidia.com/download/index.aspx
To use ray tracing, you will also need a GPU that supports it. That includes all GPUs with RTX in the name. Pascal or Turing GPUs do not support the required extensions. AMD GPUs of the Radeon RX 6000 series should also work but have not been tested.
You can run the application without ray tracing but your driver has to support Vulkan 1.2. If the demo does not start, take a look at its command line output.
Important Code Files
The GLSL implementation of our techniques is found in: src/shaders/polygon_sampling.glsl src/shaders/line_sampling.glsl (on the corresponding branch)
The complete shading pass, including our multiple importance sampling, is part of: src/shaders/shading_pass.frag.glsl
Licenses
Most code in this package is licensed under the terms of the GPLv3. However, you have the option to use the core of the sampling methods in polygon_sampling.glsl and line_sampling.glsl under the BSD license. See the comments at the top of each file for details.
