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Here are a few different solutions to determine if a point is in a polygon with code examples. I think solution 3 might be applicable and faster. Section: Dete

Here are a few different solutions to determine if a point is in a polygon with code examples. I think solution 3 might be applicable and faster. Section: Determining if a point lies on the interior of a polygon http://paulbourke.net/geometry/polygonmesh/ http://paulbourke.net/geometry/polygonmesh/

bazzargh 14y ago
Yup, that looks right, but it can be made even simpler in this case because one of the segments is always vertical. var prevOffset = prev.x-lowerRight.x; loc.x < lowerRight.x && (loc.y-prev.y)*-prevOffset-(loc.x-prev.x)*(upperRight.y-prev.y) <0 && (loc.y-lowerRight.y)*prevOffset-(loc.x-lowerRight.x)*(prev.y-lowerRight.y) < 0 This is in fact equivalent to what's in jQuery.menu-aim.js, eg upperSlope < prevUpperSlope => upperSlope - prevUpperSlope < 0, then inline slope() and multiply through by the denominators. I'd prefer the code above though, as there's no icky division by zero.