Bodies can enter the seams of a concave polygon

For a game, I’ve created a static donut-like boundary polygon through an inner & outer set of circular points with Matter.Bodies.fromVertices. I have some players inside it represented here as simple Matter.Bodies.circles. Random 360 degree movement is applied to them through what I think is a fairly weak Matter.Body.applyForce, and it all seems to interact correctly, but if the player applies force at the correct angle, it seems the body can enter seams of the donut and not be pushed out.

The random movement means I haven’t really tried to see how easily this can occur by a consistently applied force, but it seems to happen surprisingly often enough this way. Is this enough information?

[liabru]

Yeah that sounds like a good idea. I think in general it’s just very difficult to fully automate robust geometry generation for physics engines, it’s a complex problem in itself and can require manual work. There’s definitely room to improve this utility though.

Hopefully you can get it working from that so I’ll close this as it’s a known issue, feel free to report back here still if you find some success.

[MattTreichelYeah]

I’d have to figure something out to do that I think, but I could believe it works. I may just go ahead with using a second offset donut to cover the seams. Thanks.