What is the optimized (avoiding square roots, trigonometry etc.) formula for hit testing given x,y point and ellipse with cx,cy center and width,height?
(Ellipse can rotate, but that's not the case.)
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madneon
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[This answer on the math site](http://math.stackexchange.com/a/229826/21117) may help. – Sergey Kalinichenko Nov 14 '15 at 23:55
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And what is the exact reason for downvote? – madneon Nov 14 '15 at 23:58
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sum of distances of (x,y) to the two foci is 2a. – Will Ness Nov 15 '15 at 00:00
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@madneon Nobody will tell you their exact reason, I'm afraid :-) – Sergey Kalinichenko Nov 15 '15 at 00:03
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@madneon Wasn't me, but I guess it was due to the apparent lack of research effort. – Andrew Morton Nov 15 '15 at 00:47