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I'm looking for a tool or algorithm to detect concave polygons and split them into convex polygons. Like explained in the picture, the blue polygon is split into A and B polygons

I'm using Arcpy under Arcgis 10.1

split polygons

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Perhaps you could elaborate on why you are doing this? After all, (a) detection is easy: a concave polygon will have less area than its convex hull; and (b) any triangulation of a polygon automatically splits it into convex polygons, because all triangles are convex. This shows you have some flexibility in choosing among the many possible solutions. – whuber♦ Oct 5 '12 at 12:42
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This toolset will enable you to see what Bill is talking about resources.arcgis.com/gallery/file/geoprocessing/… convert the polygon to points then run the Delaunay option – Dan Patterson Oct 5 '12 at 14:02
I have been convinced to just detect very concave polygons, by getting their centroid, then get the polygons having their centroid outside. – geogeek Oct 6 '12 at 10:25
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There is an answer to this over on Stack Overflow: stackoverflow.com/a/6686842/1300519 The algorithms described shouldn't be too difficult to write using arcpy. – Snorfalorpagus Dec 23 '12 at 16:47
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@snorf That appears to answer a slightly, but importantly, different question. The solution apparently involves a combination of "polygons" and "holes", which is not what is usually meant by "splitting". At the least, that answer needs further elaboration to be useful here. (BTW, your answer was changed to a comment because cross-references to other solutions elsewhere on the Web, without any additional explanation, are not considered answers here on SE.) – whuber♦ Dec 23 '12 at 21:58
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