NVRHI (NVIDIA Rendering Hardware Interface) is a library that implements a common abstraction layer over multiple graphics APIs (GAPIs): Direct3D 11, Direct3D 12, and Vulkan 1.2. It works on Windows (x64 only) and Linux (x64 and ARM64).
Key features:
- Automatic tracking of resource states and barrier placement (optional).
- Automatic tracking of resource usage and lifetime, deferred and safe resource destruction.
- Convenient and efficient resource binding model with little runtime overhead.
- Easy direct interaction with the underlying GAPI when necessary.
- Easy portability of the rendering code between the supported GAPIs.
- Hidden sub-allocation of upload buffers and versioning of constant buffers.
- Parallel command list recording and multi-queue rendering.
- Supports all types of pipelines: Graphics, Compute, Ray Tracing, and Meshlet.
- Validation layer and resource reflection for easy debugging.
NVRHI is used in several NVIDIA GameWorks SDKs:
- Adaptive and Variable-Rate Shading SDK
- Donut Framework and its Examples
- Opacity Micro-Map SDK
- Path Tracing SDK
- RTXDI SDK
Notable third-party projects using NVRHI:
Various early versions of NVRHI have been used in various projects created at NVIDIA, including:
- Windows or Linux (x64 or ARM64)
- CMake 3.10
- A C++ 17 compiler (Visual Studio 2019, GCC 8 or Clang 6)
- Windows SDK version 10.0.19041.0 or later for DX12 support
NVRHI can be configured to be used a set of static libraries in CMake-based projects, or as a single dynamic library.
To include NVRHI into a CMake project as static libraries:
- Add this repository as a submodule.
- Add a
add_subdirectory(nvrhi)
directive to the parent CMakeLists.txt. - Add dependencies to the necessary targets:
nvrhi
for the interface headers, common utilities, and validation;nvrhi_d3d11
for DX11 (enabled whenNVRHI_WITH_DX11
isON
);nvrhi_d3d12
for DX12 (enabled whenNVRHI_WITH_DX12
isON
); andnvrhi_vk
for Vulkan (enabled whenNVRHI_WITH_VULKAN
isON
).
To build NVRHI as a shared library (DLL or .so):
- Clone this repository recursively (including submodules).
- Generate the project with CMake:
- Set the
NVRHI_BUILD_SHARED
variable toON
. - Make sure to set the target platform to a 64-bit one. 32-bit builds are not supported.
- Set the
- Build and install as normal.
See the programming guide and the tutorial.
The batch shader compiler that is included with NVRHI is superseded by ShaderMake and will be removed soon. Please update your projects to use ShaderMake.
Command line differences between nvrhi-scomp
and ShaderMake
:
-i/--infile
replaced with-c/--config
.-p/--parallel
is now the default behavior, use--serial
to get single-thread compilation.--keep
removed.--ignore
replaced with--relaxedInclude
.--cflags
removed to support API interaction with the compilers, use individual feature settings instead.--platform
arguments now need to be uppercase:DXIL
,DXBC
,SPIRV
.--vk-{s,t,b,u}-shift
replaced with--{s,t,b,u}RegShift
- Add
--useAPI
on Windows to improve compilation performance.
Config file differences:
-T <type>_<model>
replaced with just-T <type>
, and the shader model is now specified from ShaderMake command line with--shaderModel <model>
.- Comments now start with
//
instead of#
. - Added limited support for
#ifdef
and similar preprocessor directives to conditionally compile shaders.
The format of shader permutation blobs remains the same, but NVRHI will no longer support it once ShaderCompiler is removed. Use the new ShaderMakeBlob
library instead of createShaderPermutation
and createShaderLibraryPermutation
to parse the blobs on the application side.
The shader compiler target and its dependency cxxopts
can be removed from build by setting NVRHI_WITH_SHADER_COMPILER
to OFF
in CMake configuration.
NVRHI includes optional support for certain DX11 and DX12 extensions available through the NVAPI library. The library is not distributed with NVRHI but is available separately here.
To enable NVAPI support, extract the NVAPI SDK into the nvapi
subfolder of your main project and set the NVRHI_WITH_NVAPI
CMake variable to ON
.
The following extensions are supported:
- Opacity Micro-Maps (DX12, Ada+)
- Shader Execution Reordering on DX12 (DX12, Ada+)
- Single Pass Stereo (Pascal+)
- Fast Geometry Shader with optional coordinate swizzling (Maxwell+)
- Conservative Raster and other rasterizer features (Maxwell+)
- HLSL Extensions through a fake UAV slot (see this blog post)
NVRHI includes an optional integration of the RTXMU library. The library is included as a git submodule, and can be enabled with the NVRHI_WITH_RTXMU
CMake variable.
When RTXMU integration is enabled, all bottom-level ray tracing acceleration structures (BLAS'es) are managed by that library. All built BLAS'es that have the AllowCompaction
flag set are automatically compacted when ICommandList::compactBottomLevelAccelStructs
method is called. No other configuration is necessary.
NVRHI is licensed under the MIT License.