Geometry Boost List: [ggl] Polygon difference

Subject: [ggl] Polygon difference
From: Vish (vrang3)
Date: 2011-01-09 21:35:03

Hello,

I get an empty polygon list from a polygon difference calculation 'a NOT 
b'. Neither polygon 'a' nor 'b' has a hole and 'b' is completely inside 
'a'. Polygons 'a' and 'b' are passed into an intersection_inserter after 
reversing the boundary of 'b'.

I read the posting of Feb 28, 2010 titled "XOR and/or DIFFERENCE boolean 
polygon combination". In that posting, a problematic case was described, 
when rings of 'b' do not intersect rings of 'a'. It was mentioned that 
some additional work needed to be done to assemble the rings.

Does this problematic case remain unresolved, and if so, is there a 
workaround?

Vishnu