OpenRHI — orhi — is a lightweight, permissive, cross-platform Render Hardware Interface for modern graphics APIs, built with C++20.

Write hardware-agnostic graphics code once, and run it seamlessly across multiple platforms and graphics APIs.

OpenRHI is...

• 🧩 Simple: Easy to understand and extend
• ⚡ Fast: Minimal runtime overhead with template-based design
• ⛓️‍💥 Standalone: Zero external dependencies
• 📃 Documented: Comprehensive source code documentation
• 🌈 Cross-platform: Native support for Windows, macOS, and Linux
• ⚙️ Build-ready: Quick setup with CMake

Goals:

• Provide a thin, explicit abstraction over modern graphics APIs
• Offer low-level access to each backend through a unified interface
• Maintain explicitness: no hidden logic or implicit behavior
• Ensure minimal runtime overhead with zero-cost abstractions
• Remain cross-platform and hardware-agnostic
• Maintain minimal external dependencies

Non-Goals:

• Hiding platform or API-specific implementation details
• Acting as a high-level rendering engine or framework
• Abstracting away or simplifying modern graphics concepts
• Automatically managing resources, pipelines, or synchronization

OpenRHI primarily targets desktop platforms, with an API architecture designed for maximum flexibility to support any backend your application needs.

Target platforms: Windows (🪟), Linux (🐧), and macOS (🍎)

OpenRHI supports compiling with multiple graphics APIs simultaneously.

You can also choose which graphics API serves as the default backend for API-agnostic objects, while still having access to backend-specific implementations when needed.

#include <orhi/Buffer.h>

orhi::Buffer buffer{};

#include <orhi/impl/vk/Buffer.h>
#include <orhi/impl/mock/Buffer.h>

orhi::impl::vk::Buffer vulkanBuffer{};
orhi::impl::mock::Buffer mockBuffer{};

OpenRHI comes with a set of examples for you to try.

Windows:

git clone https://github.com/adriengivry/orhi --recurse-submodules
cd .\orhi
.\gen_proj_win32.bat
.\build\orhi.sln # (optional) open solution in Visual Studio

Linux:

git clone https://github.com/adriengivry/orhi --recurse-submodules
cd ./orhi
./gen_proj_linux.sh

All contributions to OpenRHI are welcome — from bug reports and feature suggestions to code improvements and documentation enhancements.

Feel free to open issues or submit pull requests for review. Every contribution helps make OpenRHI better!

For more information on contributing, check out CONTRIBUTING.md.

By contributing, you agree that your contributions will be licensed under the MIT License.

OpenRHI is licensed under the MIT License.

You are free to use, modify, and distribute this project with proper attribution. See the license file for more details.