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JavaScript Separate Axis Theorem

I am trying to wrap my head using the dividing axis theorem in JavaScript to detect two squares colliding (one turned, one not). As far as I try, I can’t figure out how this will look in JavaScript, and I won’t be able to find any JavaScript examples. Please help, an explanation using primes or JavaScript code will be most helpful.

Update: After learning a lot of geometries and mathematical theories, I decided to release a simplified implementation of SAT in the GitHub repo. You can find a working copy of SAT in JavaScript here: https://github.com/ashblue/canvas-sat

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var p0 = edge[0]; // first point of edge
var p1 = edge[1]; // second point of edge
var v = p1.subtract(p0);
var normal = new Vector3D(0, 0, 1).crossProduct(v);
normal.normalize();

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// point is the point to classify as "in front" or "behind" the edge
var point = point.subtract(p0);
var distance = point.dotProduct(normal);
var inFront = distance >= 0;

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