Re: Point in Poly formula

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BigAl.NZ@xxxxxxxxx wrote:
> Right, so they are a set of x,y co-ords that define one edge of the
> polygon?
>
> And is "C = !C" equate to C = NOT C? I dont quite get what the C is
> doing? Its defined initally at 0 and the for loop runs through, but
> that does not seem to affect the value of C???

yes it means c= NOT c and in fact it effects the c value in the loop.
The c=!c line does alternate the c with 1 and 0 every time this line is
executed. The idea is, that if you cross an even number of edges from the given
point you're point is outside and if its odd its inside. You could also use
something like c++; and instead of return c you use return c%2.

Regards
Stefan

>
> Cheers
>
> -Al
>

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