Concepts

Concepts
concept	EnvelopeTraits_3
	This concept defines the minimal set of geometric predicates and operations needed to compute the envelope of a set of arbitrary surfaces in $\mathbb{R}^3$. It refines the ArrangementXMonotoneTraits_2 concept. In addition to the Point_2 and X_monotone_curve_2 types and the Has_boundary_category category tag listed in the base concept, it also lists the Surface_3 and Xy_monotone_surface_3 types, which represent arbitrary surfaces and $xy$-monotone surfaces, respectively, and some constructions and predicates on these types. Note however, that these operations usually involve the projection of 3D objects onto the $xy$-plane. More...