processing/processing4

[!NOTE] Processing 5.0 development is underway on main.

• New features and 5.0 work: Open pull requests against main.
• Bug fixes for Processing 4: Open pull requests against the 4.x branch.

Not sure which branch to use? Ask in the issue thread or on Discord in #devs-chat.

Processing is a flexible software sketchbook and a programming language designed for learning how to code.

This repository contains the source code for the Processing project for people who want to help improve the code.

We welcome new contributors! Join us on the Discord Server, and see the Contributor Guide for guidelines and tips on getting started.

Acknowledgement

Processing was initiated in 2001 by Ben Fry and Casey Reas, who led the development and maintenance of the project until 2023. We are grateful for their vision and dedication to the project. Processing is also indebted to over two decades of contributions from the broader Processing community.

Using Processing

If you're interested in using Processing, head over to the download page, or read more about the project on the Processing website. There are also several tutorials that provide a helpful introduction. They are complemented by hundreds of examples that are included with the software itself.

Getting Help

For assistance with your own sketches, projects, or code, please post your question on the Processing forum: https://discourse.processing.org/. Our community is full of experienced developers and knowledgeable users who are eager to help. Before you post, please take a moment to read the guidelines on asking questions to make sure you get the best possible help. We’re incredibly grateful for the support and knowledge shared by everyone on the forum over the years.

Contributing to Processing

Processing is a labor of love, built over decades by people who believe in this community and genuinely enjoy contributing to it. If you want to fix a bug that’s been bothering you or give back to the project in other ways, you’re in the right place! We invite you to think of this repository as a community garden. We’re here to cultivate something beautiful together, and that takes kindness, dedication, and patience. For detailed guidelines on how to contribute, please see our CONTRIBUTING.md.

We understand that contributing to open source can be intimidating, but mistakes are part of learning—and we are all learners here. We do not assume knowledge or imply that somebody should already know any particular thing in order to contribute. Whether you’re a newcomer or an expert, your knowledge and contributions are valuable. Never hesitate to ask questions, open an issue, a pull request, or write a comment. We also encourage you to step in if you can: reply to issues, review pull requests, or help out in whatever way feels right for you.

While we assume good intentions, and will give everyone a chance to learn, we have zero tolerance for repeated harassment, harmful behavior, or toxicity of any kind. Please read our Code of Conduct and join us in creating a safe and supportive environment through your words and actions.

AI Usage Policy

This project does not accept fully AI-generated contributions. AI tools may be used assistively only. As a contributor, you should be able to understand and take responsibility for changes you make to the codebase.

More details can be found in our AI Usage Policy and AGENTS.md.

Building Processing

Building Processing locally on your machine will let you troubleshoot and make sure your contributions work as intended before submitting them to this repository. It also gives you the flexibility to experiment and learn more about how Processing is structured.

For a quick start:

1. Fork and clone the repository
2. Open it in IntelliJ IDEA
3. Wait for Gradle to sync
4. Next to the run Button, select the Processing Configuration
5. Hit Run

For more information and detailed instructions, follow our How to Build Processing guide.

Contact Information

For technical support or troubleshooting with your project, please post on the Processing Forum.

For bug reports or feature requests, please create an issue.

For non-technical inquiries, here’s how to get in touch:

• For press inquiries, general information about the Processing software, or other non-technical questions, contact [email protected].
• For anything related to the Processing Foundation or broader topics beyond the software, please reach out to [email protected].

License & Copyright

• The core library is licensed under the GNU Lesser General Public License version 2.1 (LGPL-2.1).
• Everything else including the PDE is licensed under the GNU General Public License version 2 (GPL-2.0).
• The reference, including the JavaDoc comments, is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (CC-BY-NC-SA-4.0).

For complete licensing information about the Processing core library and software, see LICENSE.md

For licensing information about the Processing website see the processing-website README.

Copyright (c) 2015-now The Processing Foundation

Contributors

See CONTRIBUTORS.md for a list of all contributors to the project.

This project follows the all-contributors specification and the Emoji Key ✨ for contribution types. Detailed instructions on how to add yourself or add contribution emojis to your name are here. You can also post an issue or comment on a pull request with the text: @all-contributors please add @YOUR-USERNAME for THINGS (where THINGS is a comma-separated list of entries from the list of possible contribution types) and our nice bot will add you to CONTRIBUTORS.md automatically!