Concave polygon collision issue

[paulcoms]

Describe the bug

Collision detection with polygons

A clear and concise description of what the bug is.

When using concave polys the collision detection system appears to apply to the concave space

Version

What version are you running?

v3001

To Reproduce

Steps to reproduce the behavior:

1. Run in kaplayground:

// @ts-check

kaplay();

setGravity(300);

add([
    pos(0, 400),
    rect(width(), 40),
    area(),
    body({ isStatic: true }),
]);

add([
    pos(width() / 2, 100),
    polygon([vec2(0,0), vec2(0,20), vec2(40,20), vec2(40,60), vec2(60,60), vec2(60,0)],{triangulate:true}),
    color(RED),  
    area(),
    body()
]);

add([
    pos(width() / 2+40, 0),
    polygon([vec2(0,0), vec2(0,20), vec2(40,20), vec2(40,60), vec2(60,60), vec2(60,0)],{triangulate:true}),
    color(BLUE),  
    area(),
    body()
]);

Expected behavior

A clear and concise description of what you expected to happen.

I expected the polygons to only colide when they contact eachother

Screenshots

If applicable, add screenshots to help explain your problem.

[mflerackers]

That's not a bug, as the collision detection algorithm only supports convex polygons. You need to subdivide if you want to use concave shapes, or use a different collision library (though most of them also only support convex shapes, so you need to subdivide and add multiple fixtures).