Re: Checking for overlaps of rectangles

From: Shakespeare <>
Date: Tue, 07 Jul 2009 12:20:40 +0200
Message-ID: <4a532253$0$183$>

Hans Mayr schreef:
> Hello Shakespeare,
> Thanks for your answer. It is nice for me to read that you pointed out
> the problems I have seen and wrote about in my original message in the
> other group. Thanks for the hints, I will check Locator. And just the
> fact that there is something like the "Painter's Algorithm" shows that
> a solution is pretty complicated and that there obviously is no easy
> standard approach.
> Best,
> Hans


I suddenly remebered another old algorithm from the Computer Graphics courses I followed some decades ago. It is an algorithm for which you fill a 3 by 3 matrix for each combination of rectangles, with values determined by the position of the corner coordinates (left, right, above, below). The outcome in the matrix will tell you if the rectangles overlap. It's fairly simple, but I don't remember the name, nor the exact way it worked. Maybe one of the readers will remember. I'll try to find it in one of y (old) books.

Shakespeare Received on Tue Jul 07 2009 - 05:20:40 CDT

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