generate a RADIANCE description of a prism
genprism mat name
N v1 v2 .. vN
produces a RADIANCE scene description of a prism, or extruded polygon.
The polygon to extrude lies in the z==0 plane, and
is given as a list of (x,y) pairs on the
standard input (-), or from the file
or on the command line preceded by the number of vertices,
The order of the vertices and the extrusion vector
(default (0,0,1)) determine the surface orientations.
The surfaces that make up the prism will be modified by
and their identifiers will begin with
option may be used to round the corners of the object using spheres
option inhibits generation of a face connecting the last vertex to the first.
option inhibits generation of the end polygons.
To produce a equilateral triangular prism:
genprism clear_plastic prism 3 0 0 .5 .866 1 0
The rounding option only works for opaque prisms with outward facing
If the normals face inward, the appearance will be bizarre.