plot2trans: plot the 2-transition surface associated with a zonohedron

In zonohedra: Compute and Plot Zonohedra from Vector Generators

plot the 2-transition surface associated with a zonohedron

Description

The 2-transition surface has the topology of a sphere and is contained in the zonohedron. All the facets are parallelograms. The surface is centrally symmetric, with the same center as the zonohedron. The surface may have self-intersections.

Usage

plot2trans(  x, type='ef', ecol='black', econc=FALSE,
                 fcol='yellow', falpha=0.5, level=NULL,
                 normals=FALSE, both=TRUE, bgcol="gray40", add=FALSE, ... )

Arguments

x	a zonohedron object as returned by the constructor zonohedron()
type	a character string with what parts to draw. If type contains 'e', then draw the edges. If type contains 'f', then draw filled facets. If type contains 'p', then draw points at the centers of the facets.
ecol	The color to use when drawing the edges.
econc	If TRUE then draw the concave edges in red, and with extra thickness
fcol	The color to use when drawing the facets.
falpha	The opacity to use when drawing the facets.
level	An integer vector which is a subvector of 0:(M-2), where M is the number of simplified generators. Only the facets and edges at the specified levels are drawn. When level=NULL then all facets and edges are drawn. This argument does not affect the drawing of points.
normals	If TRUE then draw the unit facet normals.
both	if FALSE then draw only one half of the centrally symmetric surface. Otherwise draw both halves (the default).
bgcol	the background color
add	If TRUE then add to the current 3D plot. If there is no current 3D plot, it is an error.
...	not used

Details

Facets and regular edges are drawn with rgl::quads3d(). Concave edges are drawn with rgl::segments3d(). Points are drawn with rgl::points3d().

Value

The function returns TRUE; or FALSE in case of error.

Note

The package rgl is required for 3D plots. A large black point is drawn at 0, a large white point at the "white point", and a 50% gray point at the center. A line from the black point to the white point is also drawn.

See Also

zonohedron(), plothighertrans(), plot.zonohedron()

zonohedra documentation built on Sept. 1, 2025, 9:08 a.m.