This is a simple, brute-force ray tracer written in C# and capable of running on the CPU (using .NET Core) and on the GPU in a compute shader (using Veldrid and ShaderGen). Everything is written in C#, and a majority of the logic is shared between the versions that run on the CPU and GPU.
This is a .NET Core application, so you will need the .NET Core SDK for your platform to build and run it.
dotnet run -c Release -p raytracer.csproj
By default, the ray tracing will be done on the GPU. You can change this by setting _drawModeCPU to true. When drawing on the CPU, you may want to lower the Width and Height of the output image, as well as the NumSamples used. These are all found at the top of RayTracingApplication.cs.
You can force a different graphics API to be used by changing the backend variable at the beginning of RayTracingApplication.Run(). By default, the application will automatically choose the "platform default" graphics API.
There's two scenes included in the program. Uncomment one of the Create__Scene methods to use a different scene.
Ray Tracing in One Weekend by Peter Shirley. Most of the general structure of this ray tracer is based on the code from this book.