# 🌀 DirectX Ray Tracing Samples® Samples

Progressive DirectX Raytracing (DXR) samples built with CMake.

Each sample adds one focused concept to the previous one: first writing to a texture, then acceleration structures, vertex buffers, index buffers, constant buffers, camera matrices, and finally Dear ImGui on top of a DXR frame.

Build

cmake -S . -B build -G "Visual Studio 17 2022" -A x64
cmake --build build --config Debug

Run a sample:

.\build\Debug\ClearScreen.exe

Requirements

• Windows 10/11
• Visual Studio 2022 with the C++ desktop workload
• DirectX 12 / DXR capable GPU
• CMake 3.24 or newer

Examples

Example	Details
	ClearScreen The first DXR sample. It creates a minimal raytracing pipeline with only rayGen, writes a gradient into a UAV texture, and copies that texture to the swap chain. There is no geometry, BLAS, TLAS, miss shader, or closest-hit shader yet.
	AccelerationStructures Introduces acceleration structures. It builds a BLAS for one triangle and a TLAS that instances it. The ray generation shader fires primary rays, the miss shader writes the background, and the closest-hit shader colors the triangle.
	VertexBuffer Adds vertex-buffer reads from DXR shaders. The closest-hit shader accesses a StructuredBuffer<Vertex> SRV and uses barycentric coordinates to interpolate per-vertex colors.
	IndexBuffer Adds indexed geometry. The BLAS uses shared vertices and indices to form two triangles, and the closest-hit shader reads a StructuredBuffer<uint> to resolve each primitive's vertices.
	ConstantBuffer Adds constant buffers to the global root signature. The sample renders an indexed DXR cube, uses world/view/projection/inverseViewProjection matrices for a real camera, and rotates the cube by updating the TLAS instance transform every frame.
	ImGui Integrates Dear ImGui on top of the DXR result. It keeps the real matrix-based camera, the cube rotating through TLAS updates, and lets the UI adjust parameters before drawing ImGui over the back buffer.

Repository Layout

• Assets/Shaders: DXR HLSL libraries per sample.
• External: third-party dependencies used by Common.
• Src/Common: shared helpers for windows, descriptors, GUI integration, and DXC compilation.
• Src/<Example>: one .cpp sample file and one tutorial README.md.

Notes

• CMake generates the solution under build/.
• CMake also adds the NuGet reference to Microsoft.Direct3D.DXC.