Isn't a triangle a polygon in masking?

[biochem-fan]

Our polygon masking code rejects polygons with 3 or less vertices.

dxtbx/src/dxtbx/masking/masking.h

Lines 120 to 122 in 9e26747

	void mask_untrusted_polygon(scitbx::af::ref<bool, scitbx::af::c_grid<2> > mask,
	const scitbx::af::const_ref<vec2<double> > &polygon) {
	DXTBX_ASSERT(polygon.size() > 3);

It makes sense to reject cases with one vertex (i.e. point) or two vertices (i.e. line) but why do we reject triangles?

Changing this to

DXTBX_ASSERT(polygon.size() >= 3); 

seems working but am I missing some corner cases?

[dagewa]

Perhaps this was always meant to be >=? I can't think of any reason to reject a triangle

[biochem-fan]

@dagewa Thanks for confirmation. I made a pull request.