How do the control points in CGContextAddCurveToPoint relate to the actual curve formula

Question

I am trying to implement CGContextAddCurveToPoint() in my app. In addition to the starting point and ending points, the function also takes two control points.

I need to know the exact formula of the curve so I can calculate the shortest distance from the curve to a tapped point, so I'm just wondering if anyone know how, mathematically, the two control points affect the cubic function which it is supposed to draw.

possible duplicate of [Position of a point relative to a Bezier curve](http://stackoverflow.com/questions/920687/position-of-a-point-relative-to-a-bezier-curve) — Cyrille, Jul 22 '13 at 11:14

score 0 · Answer 1 · edited May 23 '17 at 12:29

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That's a Bézier Curve. You'll find more info about them here and there are plenty of resources on the Net about finding the "distance to a bezier curve", among which this question on SO.

edited May 23 '17 at 12:29

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answered Jul 22 '13 at 11:11

Cyrille

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Thanks :) hate vector math and wikipedia's definition but I'll hack through it :P – Flying_Banana Jul 22 '13 at 11:29

How do the control points in CGContextAddCurveToPoint relate to the actual curve formula

1 Answers1