TinyUSDZ is currently in work-in-progress. It does not compile and run. I'm rewritting TinyUSDZ to support more USD features including Composition Args.

USDC data parse
USDA parse
- Initial USDA parser starting to work(see sandbox/usda/)
- Support Blender-exported USDA support in 2022 Spring planned.
Reconstuct primitive and scene graph representaion(2022 Spring expected)
- GeomMesh
- GeomBasisCurves(for hair/fur)
- GeomPoints(for particles)
- Xform
- etc.
- Built-in usdObj(wavefront .obj mesh support)
  - See doc/usdObj.md for details.
Composition
- subLayers
- references
- payloads(delayed load)
- variants
- specializers
Write simple SDL viewer example(2022 Spring expected)
Character animation(usdSkel, blendshapes, animations) support(2022 Summer expected)
Vulkan raytracing viewer example
Viewer with Metal ray tracing API?
Polygon triangulation using mapxbo/earcut.hpp
USDZ(USDC) writer
USDA writer

Notice

TinyUSDZ does not support Reality Composer file format(.reality) since it uses proprietary file format and we cannot understand it(so no conversion support from/to Reality also).

UsdzSharpie: C# Simple implementation of Usdz file format ( https://github.com/UkooLabs/UsdzSharpie )
TinyGLTF: glTF 2.0 loader/saver ( https://github.com/syoyo/tinygltf )
TinyObjLoader: Wavefront .obj loader ( https://github.com/tinyobjloader/tinyobjloader )
USD-build-aarch64: Full USD build for AARCH64(Linux and Android): https://github.com/syoyo/USD-build-aarch64
BlenderUSDZ: It contains their own Python USDC parser/serializer. https://github.com/robmcrosby/BlenderUSDZ

Supported platforms

Linux 64bit or later
- ARM AARCH64
- x86-64
- RISC-V(Should work)
- SPARC, POWER(Big endian machine). May work(theoretically)
Android arm64v8a
iOS(Should work)
macOS
Windows 10 64bit or later
- Windows ARM(should work)
WebAssembly(through Emscripten)
- See examples/sdlviewer/ example.
- Multithreading is not available due to Browser's restriction.

Requirements

C++14 compiler
- gcc 5 or later
- Visual Studio 2019 or later(2017 may compiles)
  - Can be compiled with standalone MSVC compilers(Build Tools for Visual Studio 2019)
- clang 3.4 or later https://clang.llvm.org/cxx_status.html
- llvm-ming(clang) supported

USDZ file format

USDZ is actually the uncompressed zip file. USDZ(ZIP) contains usdc(binary) and resources(e.g. image/auduo files)

Security and memory budget

USDZ(USDC) is a binary format and data are compressed. To avoid out-of-bounds access, out-of-memory, and other security issues when loading malcious USDZ(e.g. USDZ file from unknown origin), TinyUSDZ has a memory budget feature to avoid out-of-memory issue.

To limit a memory usage when loading USDZ file, Please set a value max_memory_limit_in_mb in USDLoadOptions.

TinyUSDZ source codes are also checked by Address Sanitizer, CodeQL and Fuzzer.

Build

Integrate to your app

Recomended way is simply copy src and include folder to your app, and add *.cc files to your app's build system.

I do not recommend to use tinyusdz as a git submodule, since the repo contains lots of codes required to build TinyUSDZ examples but these are not required for your app.

Compiler defines

TINYUSDZ_USE_OPENSUBDIV : Use OpenSubviv for subdivision surface(to get smooth mesh from USD(Z) primitive). Default enabled.

CMake

cmake build is still provided for CI build. CMakeSettings.json is provided for Visual Studio 2019.

Cmake project is not recommended for embedding TinyUSDZ to your app.

$ mkdir build
$ cd build
$ cmake ..
$ make

LLVM-MinGW build

MinGW native and cross-compiling example using llvm-mingw(clang) is provided. See scripts/bootstrap-cmake-mingw-win.sh and scripts/bootstrap-cmake-llvm-mingw-cross.sh for details.

One of benefit to use llvm-mingw is address sanitizer support on Windows app.

To run app(.exe, you'll need libunwind.dll and libc++.dll on your working directory or search path)

For Windows native build, we assume ninja.exe is installed on your system(You can use it from Meson package)

CMake build options

TINYUSDZ_BUILD_TESTS : Build tests
TINYUSDZ_BUILD_EXAMPLES : Build examples(note that not all examples in examples folder are built)
TINYUSDZ_WITH_OPENSUBDIV : Use OpenSubviv to tessellate subdivision surface.
- OpenSubdiv code is included in TinyUSDZ repo. If you want to use external OpenSubdiv repo, specity the path to OpenSubdiv using osd_DIR cmake environment variable.
TINYUSDZ_WITH_AUDIO : Support loading audio(mp3 and wav).
TINYUSDZ_WITH_EXR : Support loading EXR format HDR texture through TinyEXR.
TINYUSDZ_WITH_PXR_COMPAT_API : Build with pxr compatible API.

clang-cl on Windows

Assume ninja.exe is installed and path to ninja.exe is added to your %PATH%

Edit path to MSVC SDK and Windows SDK in bootstrap-clang-cl-win64.bat, then

> bootstrap-clang-cl-win64.bat
> ninja.exe

Meson

Meson build is provided for compile tests.

$ meson builddir
$ cd builddir
$ ninja

Examples

Simple dump
Simple SDL viewer
- Separated CMake build : See Readme

See examples directory for more examples.

Data format

See prim_format.md and preview_surface.md

Blender add-on(W.I.P)

Supprted Blender version

2.93 LTS(Python 3.9)

Linux

Edit path to python interpreter in scripts/bootstrap-cmake-linux-blender-pymodule.sh, then

$ ./scripts/bootstrap-cmake-linux-blender-pymodule.sh
$ cd build
$ make

Copy tinyusd_blender.*-linux-gnu.so to blender's folder. Recommended location is USER folder(~/.config/blender/2.xx)

Create scripts/addons/modules folder if required

mkdir -p ~/.config/blender/2.93/scripts/addons/modules

TODO

Built-in usdObj(wavefront .obj mesh) support.
- Through tinyobjloader.
Support Crate(binary) version 0.8.0(USD v20.11 default)
Write parser based on the schema definition.
Subdivision surface using OpenSubdiv.
- Build TinyUSDZ with OpenSubdiv(CPU)
- Replace OpenSubdiv with our own subdiv library or embree3's one.
USDA(USD Ascii) support
- Write our own USDA parser with PEG.
- USDA writer.
Animation
- Skinning(usdSkel)
- Blend shapes
  - In-between blend shapes
Audio play support
- Play audio using SoLoud or miniaudio(or Oboe for Android)
- wav(dr_wav)
- mp3(dr_mp3)
- m4a?
Support AR related schema(Game-like feature added by Reality Composer?)
Android example
iOS example?
CPU raytracer viewer
- sdlviewer
Viewer with Vulkan API.
Read USD data with bounded memory size. This feature is especially useful for mobile platform(e.g. in terms of security, memory consumption, etc)
USDZ saver
Support Nested USDZ
UDIM texture support
Support big endian architecture.

Fuzzing test

See tests/fuzzer/

License

TinyUSDZ is licensed under MIT license.

Third party licenses

USD : Apache 2.0 license. https://github.com/PixarAnimationStudios/USD
OpenSubdiv : Apache 2.0 license. https://github.com/PixarAnimationStudios/OpenSubdiv
lz4 : BSD-2 license. http://www.lz4.org
cnpy(uncompressed ZIP decode/encode code) : MIT license https://github.com/rogersce/cnpy
tinyexr: BSD license.
tinyobjloader: MIT license.
stb_image: public domain.
dr_libs: public domain. https://github.com/mackron/dr_libs
miniaudio: public domain or MIT no attribution. https://github.com/dr-soft/miniaudio
SDL2 : zlib license. https://www.libsdl.org/index.php
optional-lite: BSL 1.0 license. https://github.com/martinmoene/optional-lite
span-lite: BSL 1.0 license. https://github.com/martinmoene/span-lite
expected-lite: BSL 1.0 license. https://github.com/martinmoene/expected-lite
any-lite: BSL 1.0 license. https://github.com/martinmoene/any-lite
string-view-lite: BSL 1.0 license. https://github.com/martinmoene/string-view-lite
mapbox/earcut.hpp: ISC license. https://github.com/mapbox/earcut.hpp
mapbox/recursive_wrapper: BSL 1.0 license. https://github.com/mapbox/variant
par_shapes.h generate parametric surfaces and other simple shapes: MIT license https://github.com/prideout/par
staticstruct: MIT license. https://github.com/syoyo/staticstruct

Languages

C++ 64.1%

JavaScript 15.5%

C 8.8%

Python 3.7%

CMake 1.5%

Other 6.2%

README.md

Tiny USDZ library

Status