dummycoor: Semi-infinite edge of the Voronoi diagram

In alphahull: Generalization of the Convex Hull of a Sample of Points in the Plane

Semi-infinite edge of the Voronoi diagram

Description

This function determines fictitious coordinates for the boundless extreme of a semi-infinite edge of the Voronoi diagram.

Usage

dummycoor(tri.obj, l1, l2, m, away)

Arguments

tri.obj	Object of class "triSht". See tri.mesh in package interp.
l1	Index of the sample point correponding to one vertex of a triangle of Delaunay that lies on the convex hull, see Details.
l2	Index of the sample point correponding to other vertex of a triangle of Delaunay that lies on the convex hull, see Details.
m	Index of the circumcenter of the triangle of Delaunay with one edge on the convex hull.
away	Constant that determines how far away the fictitious boundless extreme is located.

Details

When a triangle of the Delaunay triangulation has one of its edges (given by the segment that joins the sample points with indexes l1 and l2) on the convex hull, the corresponding segment of the Voronoi diagram is semi-infinite. The finite extreme coincides with the circumcenter of the triangle and the direction of the line is given by the perpendicular bisector of the edge that lies on the convex hull.

Value

dum	Fictitious coordinates of the boundless extreme.

See Also

delvor.

alphahull documentation built on June 16, 2022, 5:10 p.m.