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

plot2trans {zonohedra}

R Documentation

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.