Converting Disney's Moana Island Scene to USD

Motivation

As of early 2020, accessing large, production-level USD content can be a challenge outside of studios. Attempting to stress-test DCC tools and studying USD workflows for large scenes can thus be a challenge: the tools that work well for the proverbial Kitchen Set might not work as well for content structured in a different hierarchy.

Disney's Moana Island Scene being a close relative to the Kitchen Set, using it as a source of high-quality content.

Screenshots

Hibiscus asset, with Ptex textures:

View from the beach scene, without Ptex textures:

Limitations

Given the narrow use case, only some content is currently translated to USD. Some of the limitations include:

• No animations
• No curves
• Not a 1:1 mapping of the original scene hierarchy
• Limited shader graph setup (especially with regards to displacement maps)
• Textures are not copied from the source directory to the destination directory. This is only due to storage and time constraints.
• Requires a build of usdview with Ptex enabled to view textures.
• Python scripts use Sdf APIs instead of the much friendlier Usd APIs in order to efficiently batch-create Prims.

Feel free to contribute a Pull Request if you see a bug or an improvement opportunity!

Running the script

Except for the USD Python bindings, the script only relies on tqdm to print progress bars to the console during the conversion. Some assets can take a while to process.

From a terminal:

pip install -r requirements.txt
python -m moana2usd --source-dir SOURCE_DIR --dest-dir DEST_DIR

where:

• SOURCE_DIR is the location where the Moana Island Scene can be found.
• DEST_DIR is the location where the converted USD files will be written.

For the full usage options:

user@machine:~$ python -m moana2usd --help
usage: __main__.py [-h] [--source-dir SOURCE_DIR] [--dest-dir DEST_DIR]
                   [--format {sdf,usd,usda,usdc,usdz}] [--load-textures]
                   [--omit-small-instances]

Convert the Moana Island scene to USD.

optional arguments:
  -h, --help            show this help message and exit
  --source-dir SOURCE_DIR
                        Directory where the Moana Island scene is located.
  --dest-dir DEST_DIR   Output directory where the USD data will be written.
  --format {sdf,usd,usda,usdc,usdz}
                        File format to output data to.
  --load-textures       Create USD assets with Ptex textures.
  --omit-small-instances
                        Omit instantiation of small (or numerous) instances.

Running the tests

A (limited) set of tests are included in the project. To execute them, run the following command from a terminal:

python -m unittest discover