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Re: [pygame] collision detection
> I think there is a nice FAQ for comp.graphics that you really ought to
> go read.
>
> Alternatively, a regular polygon with many sides is a good
> approximation to a circle.
>
> -a
The solution is VERY easy for a circle...
Point P, with coord Px, Py
Circle C, with Center Cx, Cy, and Radius R.
If sqrt((Cx-Px)^2 + (Cy-Py)^2) <R, then the point is within the circle. The
part in front of the '<' is simply the formula for finding the distance
between two points.
One can drop the expensive SQRT op, and say (Cx-Px)^2 + (Cy-Py)^2 < R^2
IE, if the distance between P and C is < R, than the point is inside the
circle.
If it = R, the point is on the edge of circle, and well, it's a design choice
as to whether that counts as inside/outside the circle.