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Re: Circle?

Hi,

On May 9, 2005, at 3:00 PM, George Warner wrote:
On Mon, 9 May 2005 14:00:00 -0700, Ralph Brunner <email@hidden> wrote:

     float c = ( sqrt ( v.x*v.x + v.y*v.y ) < 300. ? 0. : 1. );

the built-in function distance() is usually faster than using sqrt


What he said plus if you're using the result with a comparison then it's
faster to square (multiply) the other side rather than do the sqrt:

float c = ( ( v.x*v.x + v.y*v.y ) < (300.0f * 300.0f) ? 0.0f : 1.0f );
True -- I was just assuming that everybody wants anti-aliased circles :) The simple inside/outside test above is indeed faster if you don't care about AA edges.
- Ralph

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