Hi, one week ago I posted a mail searching for mentors for a Boost.Geometry idea about implementing the basic set operations (difference, union_, sym_difference) for <box,box,Collection<box> and I was happy to see interest voiced by Vissarion and Adam. I have now completed my proposal with a slightly extended version of that idea and I'd be thankful for any comments: https://docs.google.com/document/d/1gNtqTbkDVXp9dPCRZZut4bBgjvQwJNdoV-EJOrE1... I've also improved my proof of concept/self-designed competency test, added a check for correctness and committed it to the github repository: https://github.com/tinko92/boost_geometry_difference_demo It now includes a patch for the boost_1_66_0 source tree, that allows tests of that implementation with the proper call: boost::geometry::difference(box1,box2,box_vector) (hopefully, if I didn't break anything I didn't see) without breaking it for other geometries. This was tested on GCC (main.cpp can be built if the folder tree from the repository is copied to some directory XYZ with the command g++ main.cpp -o main -IXYZ), VC9 and VC15. Thanks in advance for any comments on the proposal or the preliminary implementation of difference. Best, Tinko -- Sent from: http://boost.2283326.n4.nabble.com/Boost-Dev-f2600599.html