HIP RT SDK

This repository is only for tutorials. The SDK binaries needs to be downloaded from HIP RT project page and the full source code of HIP RT can be found here.

HIP RT is a ray tracing library in HIP. The APIs are designed to be minimal and low level, making it easy to write a ray tracing application in HIP. We designed the library and APIs to be simple to use and integrate into any existing HIP applications. Although there are a few other ray tracing APIs which, we designed HIP RT to be simpler and easier to use, so you do not need to learn many new kernel types.

Features

• Ray-triangle intersection
• Ray-custom primitive intersection
• Ray mask to filter geometries
• Several bounding volume hierarchy (BVH) options
• Offline BVH load and store
• BVH import
• Motion blur

Requirement

HIP RT runs on AMD and NVIDIA® GPUs. HIP and CUDA® APIs are dynamically loaded so you do not need to have these SDKs if your have these DLLs installed with the driver package. Hardware-accelerated ray tracing only works on RDNA™ 2 GPUs (Radeon™ RX 6000 series or newer).

The supported AMD GPU architecture families are:

• Navi3x (Radeon™ RX 7000 series)
• Navi2x (Radeon™ RX 6000 series)
• Navi1x (Radeon™ RX 5000 series)

You will also need AMD Software: Adrenalin Edition 23.30 or later for Windows and ROCm 5.7 for Linux.

Directories

• hiprt
  • The header and the library which you need to download from HIP RT prject page.
• tutorials
  • Tutorial source code
• contrib
  • External dependencies

Building the tutorials

1. First you need to clone the repository, then init and update the submodules if you didn't clone with --recursive:

git submodule init
git submodule update

2. Download the HIP RT SDK from HIP RT prject page, copy hiprt directory here.

Windows:

3. Run premake to generate a solution for Visual Studio 2022:

   cd tutorials
   "../tools/premake5/win/premake5.exe" vs2022

4. Open the solution, compile & run.

Linux:

3. Run premake like this on Windows, which will generate a make file:

   cd tutorials
   ../tools/premake5/linux64/premake5 gmake2

4. Compile using the make file & run.

   cd build
   make

These tutorials are made to run on both AMD and NVIDIA by specifying the device index.

Introduction to the HIP RT APIs

The minimum example can be found at tutorials/00_context_creation/main.cpp. On AMD platforms, you need to create a HIP context and device to initialize hiprt using hiprtCreateContext by passing hiprtContextCreationInput object where you need to set the native API context, device, and device type (HIP or CUDA).

After that, use hiprtCreateGeometry and hiprtBuildGeometry to create hiprtGeometry. Once you have finished setting up objects on the host side, you can pass the context object to your kernel.

An example of a minimum kernel can be found at here. This is a simple HIP kernel that we are passing hiprtGeometry to. To perform an intersection test, simply fill in hiprtRay, then create a hiprtGeomTraversalClosest object, then call getNextHit(). It is that simple.

References

• Introducing HIP RT – a ray tracing library in HIP, GPUOpen Blog
• HIP Ray Tracing 2.0 introduces improved custom function handling, Bitcode linking, and more, GPUOpen Blog
• Introducing HIP RT v2.1 - batch construction for small geometries, transformation query functions, and more, GPUOpen Blog
• Introducing HIP RT v2.2, GPUOpen Blog