Re: point yes/no within a specific area


martijn wrote:
Hello

How can one determine wether a point in R2 (x,y) lies within or out of a
pre-defined area described by n points x1,y1 x2,y2 ... xn,yn ??

Perhaps a commonly used algorithm exsists for this problem?

Yes. You are asking if a point falls in a polygon. This operation is
often needed in computer graphics, and so the best place to look is
in graphics sites, for instance the FAQ for comp.graphics.algorithms.

http://www.faqs.org/faqs/graphics/algorithms-faq/

Read "Subject 2.03: How do I find if a point lies within a polygon?"

- Randy

.

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