Contributing to USD

We’re excited to collaborate with the community and look forward to the many improvements you can make to USD!

Contributor License Agreement

Before contributing code to USD, we ask that you sign a Contributor License Agreement (CLA). At the root of the repository you can find the two possible CLAs:

  1. USD_CLA_Corporate.pdf : please sign this one for corporate use

  2. USD_CLA_Individual.pdf : please sign this one if you’re an individual contributor

Once your CLA is signed, send it to usd-cla@pixar.com (please make sure to include your github username) and wait for confirmation that we’ve received it. After that, you can submit pull requests.

Coding Conventions

Please follow the coding convention and style in each file and in each library when adding new files.

Pull Request Guidelines

  • All development on USD should happen against the “dev” branch of the repository. Please make sure the base branch of your pull request is set to the “dev” branch when filing your pull request.

  • Please make sure all tests are passing with your change prior to submitting a pull request.

  • We highly recommend posting issues on GitHub for features or bug fixes that you intend to work on before beginning any development. That way, if someone else is working on a similar project, you can collaborate, or you can get early feedback which can sometimes save time.

  • Please make sure that your pull requests are clean. Use the rebase and squash git facilities as needed to ensure that the pull request is as clean as possible.

  • Please make pull requests that are small and atomic - in general, it is easier for us to merge pull requests that are small and serve a single purpose than those that are sweeping and combine several functional pieces in a single PR.

Git Workflow

Here is the workflow we recommend for working on USD if you intend on contributing changes back:

  1. Post an issue on github to let folks know about the feature or bug that you found, and mention that you intend to work on it. That way, if someone else is working on a similar project, you can collaborate, or you can get early feedback which can sometimes save time.

  2. Use the github website to fork your own private repository.

  3. Clone your fork to your local machine, like this:

    git clone https://github.com/you/USD.git

  4. Add Pixar’s USD repo as upstream to make it easier to update your remote and local repos with the latest changes:

    cd USD
git remote add upstream https://github.com/PixarAnimationStudios/USD.git

  5. Now fetch the latest changes from Pixar’s USD repo like this:

    git fetch upstream

  6. We recommend you create a new branch for each feature or fix that you’d like to make and give it a descriptive name so that you can remember it later. You can checkout a new branch and create it simultaneously like this:

    git checkout -b dev_mybugfix upstream/dev

  7. Now you can work in your branch locally.

  8. Once you are happy with your change, you can verify that the change didn’t cause tests failures by running tests from your build directory:

    ctest -C Release

  9. If all the tests pass and you’d like to send your change in for consideration, push it to your remote repo:

    git push origin dev_mybugfix

  10. Now your remote branch will have your dev_mybugfix branch, which you can now pull request (to USD’s dev branch) using the github UI.