Calling remove_spikes on the resulting polygon,
and outputting it as WKT, results in the following (boost
1.56.0):
POLYGON((2079 1968))
My questions:
-
Is this expected (no closing point)?
-
I presume that for some algorithms (which?) the
position of the single point makes a difference while for
others, like difference, any empty polygon should create the
same result. Is this correct?
-
A year ago I made a note in my code that some
algorithms cannot deal with input polygons that contain
spikes (Boost.Geometry Overlay invalid input exception
results). Therefore I established an invariant for my own
polygons, that requires all polygons to be free of spikes.
Is this still necessary?
-
How is a single-point polygon different from a
spike?
-
If spikes are not allowed, how should
single-point polygons be dealt with? Should they be
considered empty, and have their last remaining point
removed before passing them to, e.g., the difference
algorithm? Or is some wrapper code required that avoids
calling certain algorithms with single-point polygons?
My internal representation is oriented
counter-clockwise and not closed, my point type is based on
int.