Hello Clipper, bye JTS

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Polygon clipping and polygon offsetting are operations that due to the multitud of cases possible are quite a difficult beast to tame. That is why I have used an external library when I have needed such a feature in a program.

A few days ago, researching for a student's assignment, I learned that "clipper" library had been migrated to Java by Tobias Mahlmann.  I had a minor trouble with one file not using UTF-8 encoding but other than that it compiled and run beautifully (not in my large display though as I am using an scale factor larger than one that messes the Java GUI layout).


Another interesting detail is that the code will need Java 1.8 to compile as it uses a Lambda function in one of the Comparators used. However, I wanted to use it with some older code that was using 1.6 and the compiler was not happy with my version request, so I needed to do a small change to get rid of the Lamba function code in favor of an inner class. 

Once the code was working, I could use it with some code developed with Processing 2.21 and it would work ok.  Now I have to do some tests but my first impression is that Clipper is way faster than Java Topology Suite.

Update: After some tests it seems Clipper is not as robust as JTS, so I am not going to make any change to my software after all.

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