gatling
Evermotion Scene 06 AI48, rendered in Gatling using Blender's Hydra/MaterialX support.
Porsche 911 GT3, modified with materials from the GPUOpen MaterialX library.
About
This is my toy path tracer I work on in my free time.
It is exposed as an OpenUSD Hydra render delegate that implements the MaterialX, NVIDIA MDL and UsdPreviewSurface material standards. As a result, it supports complex BSDFs like OpenPBR.
Gatling runs on Vulkan ray tracing and Apple M3+ processors. Tested in CI:
Build
There are prebuilt binaries which can be copied to the
Alternatively, for a full source build you need to
- download the MDL SDK 2024.1.4 binaries
- download or build USD 24.11+ with MaterialX support
Note: it is recommended to have NASM 2.13+ or YASM 1.2.0+ in your PATH to speed up image decoding.
Do a recursive clone of the repository and set up a build folder:
git clone https://github.com/pablode/gatling --recursive
mkdir gatling/build && cd gatling/build
Pass following parameters in the CMake generation phase:
cmake .. -Wno-dev \
-DUSD_ROOT= \
-DMDL_ROOT= \
-DCMAKE_INSTALL_PREFIX=/plugin/usd
-DCMAKE_BUILD_TYPE=Release
Build the relevant targets and install the Hydra delegate to the USD plugin folder:
cmake --build . --target hdGatling --config Release
cmake --install . --component hdGatling
Usage
Gatling can be used by every application which supports Hydra, either natively or through a plugin.
Alex Trevino's Junk Shop (CC BY), distilled to UsdPreviewSurfaces, rendered within usdview.
A headless standalone is provided that accepts a USD file (.usd, .usda, .usdc, .usdz) as input. It exposes the Hydra render settings as command line arguments:
./bin/gatling render.png \
--image-width 1200 \
--image-height 1200 \
--spp 1024 \
--max-bounces 8
Note: high sample counts may require adjusting the system watchdog settings.
Issues
Certain USD prim types (curves, cylinder lights), APIs (UsdLuxShapingAPI, UsdLuxShadowAPI) and features (subdivision, UDIM, volumes, displacement) are not yet supported.
License
Gatling is licensed under the GNU General Public License, as included in the LICENSE file.
Copyright (C) 2019 Pablo Delgado Kramer
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see
Licenses of third-party code and libraries are listed in the same file.