box2d: polygon mode is back

[GarboMuffin]

How it works: https://muffin.ink/slop/polygon.html

tl;dr scan costume pixels to generate polygon instead of relying on actual SVG path elements as the original one from griffpatch

Demonstration of the difference:

Screencast_20260516_223905.webm

[Brackets-Coder]

Interesting that Claude could create a prototype. The code looks great, but of course I'd be interested in more optimized/prettier/human-like versions of this that are more cohesive with the rest of the extension

On a side note, I'd be willing to work on getting Scratch.external into this thing. As for an external kripken made an emscripten port of the original C-based Box2d https://github.com/kripken/box2d.js. Same person that ported Ammo physics. I don't know if it's in parity with the version here (probably not) but we should likely just find a way to modularize and minify the library in the extension to host it on this repo

[GarboMuffin]

Screencast_20260517_121458.webm

[Brackets-Coder]

Most impressive

[GarboMuffin]

the state of this one is that it seems to work about as good as one would expect tracing image pixels to work

[SharkPool-SP]

seems fine to me. I havent checked the full box2d codebase, only the given changes. Does the sillouette to polygon thing cache? If not it would be a good thing to add before merging.

[GarboMuffin]

!format