Box2D Polygon Not Clockwise?

[Jacob]

I have a polygon, created by a CSV string, that Box2D says is not clockwise. It is u_ u

"0,35,174,3,197,3,228,9,249,24,266,46,278,69,291,9 8,300,120,304,139,304,143,0,143"

[Jacob]

Oh. I figured it out. Apparently it won't work if it's clockwise, needs to be counter-clockwise.

[Werbad]

The problem is that the polygon has parallel edges. There are multiple points on the same edge in your polygon and this is not allowed. Removing these points will solve the problem.

[Jacob]

Well, I don't see why inverting the order of the vertices fixed it then.

What is the most efficient way to test how many times a body collides with another body or an edge chain (collectively)? I tried straight collision testing, but it seems to work for more than just the body I specify.

[Werbad]

No idea why reversing the order worked, that should have caused even more Assertions...

Something like this should work, assuming you're registering collisions properly:

* On Collision Begin
+ "BodyID" of "Object" = CollBody1("Phizix")
> Add 1 to counter

Where BodyID is a value on the object holding it's Body ID.
You can choose a more specific collision condition if your objects have collision types.