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A simple polygon has a non-intersecting boundary, while a complex polygon has an intersection somewhere. So a natural approach would be to check whether any two sides of the polygon intersect each other.<br />
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The intersection of 2 lines can be tested with an algorithm like this:<br />
<a href="http://www.macs.hw.ac.uk/~alison/ds98/node114.html" rel="ugc">http://www.macs.hw.ac.uk/~alison/ds98/node114.html</a><br />

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I've tried doing an edge-edge test, but it fails for some reason. Could it be that an edge sharing the same node brings back true when doing the edge on edge test?
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Yes, this sounds plausible. But you can simply omit to test the neighbor edges as they will never intersect each other.
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I have two arrays, storing the x and y values of the polygon. <br />
<br />
I want to find out whether the polygon is simple or complex.<br />
<br />
The polygon can be concave and is 2d.<br />
<br />
Can someone possibly provide suggestions.<br />
<br />
Many Thanks.
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I have two arrays, storing the x and y values of the polygon. 

I want to find out whether the polygon is simple or complex.

The polygon can be concave and is 2d.

Can someone possibly provide suggestions.

Many Thanks.

A simple polygon has a non-intersecting boundary, while a complex polygon has an intersection somewhere. So a natural approach would be to check whether any two sides of the polygon intersect each other.

The intersection of 2 lines can be tested with an algorithm like this:
http://www.macs.hw.ac.uk/~alison/ds98/node114.html


I&#39;ve tried doing an edge-edge test, but it fails for some reason. Could it be that an edge sharing the same node brings back true when doing the edge on edge test?

Yes, this sounds plausible. But you can simply omit to test the neighbor edges as they will never intersect each other.

Determine whether a polygon is complex or simple

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