Hey, I was doing the nodes tutorial on bit-101.com, a great tutorial by the way, and I was just wondering where this distance formula comes from. I understand x2 - x1 and y2 - y1, but where does that square root of dx^2 + dy^2 come from? Thanks!
dx = thingA._x - thingB._x;
dy = thingA._y - thingB._y;
dist = Math.sqrt(dx*dx+dy*dy);