Computing intersection areas of overlaid 2D meshes

Parover2 is a parallel algorithm and preliminary implementation to compute the area of every nonempty intersection of any face of one 2D mesh with any face from another mesh over an overlapping domain. This is the hard part of cross-interpolating data from one mesh to another, for when the faces one mesh have an attribute that would be useful for the faces of the other mesh. Parover2, implemented using a map-reduce paradigm in Thrust, can quickly process millions of faces. The expected execution time is linear in the number of intersections, which is usually linear in the number of input faces. A uniform grid quickly determines the pairs of input edges that might intersect. Local topological formulae compute the areas of the output faces from the sets of their (vertex, edge) adjacencies w/o needing to compute the faces' global topologies.