Hello Processing community!

First of all, thank you to all of the Processing and p5.js developers! I have been lurking in the shadows of your great work for several years now. I teach Math and Computer Science at a girls’ school in Los Angeles, and we use Processing extensively in our computer science classes (and recently more p5.js since the pandemic).

For a while I was using processing.js to put Processing sketches on web pages, but that project is no longer maintained.

So I wanted to share with you my processing-p5-convert project, which is a source code translator from Processing/Java to p5.js/Javascript.

You can convert Processing code directly on that web page, and it will convert to p5.js and run the sketch. You can also install and run the tool on the command line. On that web page I’ve also documented all of the code transformations needed to make things work.

I hope this is useful to some of you in the Processing community! While it’s working for my examples, I’m sure it’s missing stuff, so please let me know if you find a bug or any weird behavior. If you find something, please fill out an Issue on the GitHub page with the offending Processing code.


Congrats! I quickly tested and found that ArrayList doesn’t work, but is it supposed to work or not implemented?? Also I found a bug on WEBGL, which I posted on github.

Hi Naoto,

Yes, ArrayList should work – I’m prepending a simple ArrayList implementation (over Javascript Array) to the JS code:

But you also may have found another bug.

Thank you for posting the other issue on GitHub – it’s fixed now.