@davepagurek/flo-mat/src/geometry/get-closest-square-distance-to-rect.ts

Medial / Scale Axis Transform (MAT/SAT) Library.

import { squaredDistanceBetween as squaredDistanceBetween_ } from 'flo-vector2d';

const squaredDistanceBetween = squaredDistanceBetween_;


/**
 * @internal
 */
function getClosestSquareDistanceToRect(
		box: number[][], p: number[]): number {

	const p0 = box[0];
	const p1 = box[1];
	const x0 = p0[0];
	const y0 = p0[1];
	const x1 = p1[0];
	const y1 = p1[1];	
	const xp = p[0];
	const yp = p[1];

	//let [[x0,y0],[x1,y1]] = box;
	//let [xp,yp] = p;
	
	if (xp < x0) {
		if (yp < y0) {
			return squaredDistanceBetween(box[0], p);
		} else if (yp > y1) {
			return squaredDistanceBetween([x0,y1], p);
		} else {
			return (x0 - xp)**2;
		}
	} else if (xp > x1) {
		if (yp < y0) {
			return squaredDistanceBetween([x1,y0], p);
		} else if (yp > y1) {
			return squaredDistanceBetween(box[1], p);
		} else {
			return (xp - x1)**2;
		}
	} else {
		if (yp < y0) {
			return (y0 - yp)**2;
		} else if (yp > y1) {
			return (yp - y1)**2;
		} 
			
		return 0;
	}
}


export { getClosestSquareDistanceToRect }