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pol_recip - polar reciprocals (duals)
pol_recip [options] [input_file]
Read a file in OFF format and make a polar reciprocal from the face planes.
- input_file
- input file in OFF format, or if not given the program reads from stdin
- -h
- program help
- -c <cent>
- centre of reciprocal sphere, in form x_val,y_val,z_val, or C
to use centroid (default: 0,0,0)
- -r <rad>
- radius of reciprocal sphere (default: 1)
- -R <elms>
-
radius of reciprocal sphere using elements
- v - nearest vertex distance
- V - furthest vertex distance
- e - nearest edge distance
- E - furthest edge distance
- f - nearest face distance
- F - furthest face distance
- X - topological dual using face centroids for dual vertices
or a comma separated list of vertex indices (starting from 0)
and the distance is to the space containing those vertices
- -I <dist>
- maximum distance to project any normal or infinite dual vertex
(default: 1e15), if 0 then use actual distances and delete
infinite points
- -o <file>
- write output to file, if this option is not used
the program writes to standard output
Make a reciprocal pair. Make the dual of a cuboctahedron, a rhombic
dodecahedron, and then make the dual of that. The final output is
the same as the original cuboctahedron.
pol_recip -o rh_dodec.off -R e cuboct.off
pol_recip -o orig_cuboct.off -R e rh_dodec
Make a cube whose vertices are the mid-points of an octahedron's faces
pol_recip -o cube.off -R f octahedron.off
A polyhedron has a face made of vertices with indexes 0, 2, 4.
Make a dual which has a vertex in the plane of this face
pol_recip -o dual.off -R 0,2,4 poly.off
A dual of a convex polyhedron is normally made with the centre of
reciprocation at the polyhedron centre and the radius to just touch
the edges.
Some polyhedra have faces passing through their natural centre. This
causes a problem when making a dual because the vertex which is dual
to this face should be infinitely far away. pol_recip allows these
vertices to be included by placing them at a specified (probably very large)
distance normal to the face. Any programs dealing with these distant vertices
(e.g. povray) can interpret these distant vertices accordingly.
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geodesic - geodesic spheres
Antiprism Documentation 23.2.2007 -
http://www.antiprism.com/