Falcor

Falcor is a real-time rendering framework supporting DirectX 12 and Vulkan. It aims to improve productivity of research and prototype projects.

Features include:

• Abstracting many common graphics operations, such as shader compilation, model loading, and scene rendering
• Raytracing support
• Python scripting support
• Render graph system to build modular renderers
• Common rendering techniques such as post-processing effects
• Unbiased path tracer
• Advanced variance reduction techniques like ReSTIR PT Enhanced
• Integration of various RTX SDKs such as DLSS, RTXDI and NRD

Prerequisites

• Windows 10 version 20H2 (October 2020 Update) or newer, OS build revision .789 or newer
• Visual Studio 2022
• Windows 10 SDK (10.0.19041.0) for Windows 10, version 2004
• A GPU which supports DirectX Raytracing, such as the NVIDIA Titan V or GeForce RTX
• NVIDIA driver 535 or newer

Optional:

• Windows 10 Graphics Tools. To run DirectX 12 applications with the debug layer enabled, you must install this. There are two ways to install it:
  • Click the Windows button and type Optional Features, in the window that opens click Add a feature and select Graphics Tools.
  • Download an offline package from here. Choose a ZIP file that matches the OS version you are using (not the SDK version used for building Falcor). The ZIP includes a document which explains how to install the graphics tools.
• CUDA, OptiX (see below)

Building Falcor

Falcor uses the CMake build system. Additional information on how to use Falcor with CMake is available in the CMake development documentation page.

Visual Studio

If you are working with Visual Studio 2022, you can set up a native Visual Studio solution by running setup_vs2022.bat after cloning this repository. The solution files are written to build/windows-vs2022 and the binary output is located in build/windows-vs2022/bin.

Visual Studio Code

If you are working with Visual Studio Code, run setup.bat after cloning this repository. This will setup a VS Code workspace in the .vscode folder with sensible defaults (only if .vscode does not exist yet). When opening the project folder in VS Code, it will prompt to install recommended extensions. We recommend you do, but at least make sure that CMake Tools is installed. To build Falcor, you can select the configure preset by executing the CMake: Select Configure Preset action (Ctrl+Shift+P). Choose the Windows Ninja/MSVC preset. Then simply hit Build (or press F7) to build the project. The binary output is located in build/windows-ninja-msvc/bin.

Warning: Do not start VS Code from Git Bash, it will modify the PATH environment variable to an incompatible format, leading to issues with CMake.

Linux

Falcor has experimental support for Ubuntu 22.04. To build Falcor on Linux, run setup.sh after cloning this repository. You also need to install some system library headers using:

sudo apt install xorg-dev libgtk-3-dev

You can use the same instructions for building Falcor as described in the Visual Studio Code section above, simply choose the Linux/GCC preset.

Configure Presets

Falcor uses CMake Presets stored in CMakePresets.json to provide a set of commonly used build configurations. You can get the full list of available configure presets running cmake --list-presets:

$ cmake --list-presets
Available configure presets:

  "windows-vs2022"           - Windows VS2022
  "windows-ninja-msvc"       - Windows Ninja/MSVC
  "linux-clang"              - Linux Ninja/Clang
  "linux-gcc"                - Linux Ninja/GCC

Use cmake --preset <preset name> to generate the build tree for a given preset. The build tree is written to the build/<preset name> folder and the binary output files are in build/<preset name>/bin.

An existing build tree can be compiled using cmake --build build/<preset name>.

Falcor In Python

For more information on how to use Falcor as a Python module see Falcor In Python.

Microsoft DirectX 12 Agility SDK

Falcor uses the Microsoft DirectX 12 Agility SDK to get access to the latest DirectX 12 features. Applications can enable the Agility SDK by putting FALCOR_EXPORT_D3D12_AGILITY_SDK in the main .cpp file. Mogwai, FalcorTest and RenderGraphEditor have the Agility SDK enabled by default.

NSight Aftermath

To enable NSight Aftermath support, head over to https://developer.nvidia.com/nsight-aftermath and download the latest version of Aftermath (this build is tested against version 2023.1). Extract the content of the zip file into external/packman/aftermath.

CUDA

To enable CUDA support, download and install CUDA 11.6.2 or later and reconfigure the build.

See the CudaInterop sample application located in Source/Samples/CudaInterop for an example of how to use CUDA.

OptiX

If you want to use Falcor's OptiX functionality (specifically the OptixDenoiser render pass) download the OptiX SDK (Falcor is currently tested against OptiX version 8.0) After running the installer, link or copy the OptiX SDK folder into external/packman/optix (i.e., file external/packman/optix/include/optix.h should exist).

Note: You also need CUDA installed to compile the OptixDenoiser render pass, see above for details.

NVIDIA RTX SDKs

Falcor ships with the following NVIDIA RTX SDKs:

• DLSS (https://github.com/NVIDIA/DLSS)
• RTXDI (https://github.com/NVIDIAGameWorks/RTXDI)
• NRD (https://github.com/NVIDIAGameWorks/RayTracingDenoiser)

Note that these SDKs are not under the same license as Falcor, see LICENSE.md for details.

Resources

• Falcor: Falcor's GitHub page.
• Documentation: Additional information and tutorials.
  • Getting Started
  • Render Graph Tutorials
• Rendering Resources A collection of scenes loadable in Falcor (pbrt-v4 format).
• ORCA: A collection of scenes and assets optimized for Falcor.
• Slang: Falcor's shading language and compiler.

Citation

If you use Falcor in a research project leading to a publication, please cite the project. The BibTeX entry is

@Misc{Kallweit22,
   author =      {Simon Kallweit and Petrik Clarberg and Craig Kolb and Tom{'a}{\v s} Davidovi{\v c} and Kai-Hwa Yao and Theresa Foley and Yong He and Lifan Wu and Lucy Chen and Tomas Akenine-M{\"o}ller and Chris Wyman and Cyril Crassin and Nir Benty},
   title =       {The {Falcor} Rendering Framework},
   year =        {2022},
   month =       {8},
   url =         {https://github.com/NVIDIAGameWorks/Falcor},
   note =        {\url{https://github.com/NVIDIAGameWorks/Falcor}}
}