anytooff(1gv)anytooff(1gv)NAME
anytooff - filter to convert a (set of) geomview data file(s) containing any geomview primitives into a single polylist.
SYNOPSIS
anytooff [filename ...]
DESCRIPTION
Anytooff reads OOGL geometry data (from the given files, if any, otherwise from standard input) and outputs the new polylist (in OFF for-
mat) to standard output. Offcombine is a synonym for anytooff.
BUGS
In converting a list object, anytooff uses PLCombine(3) to merge the members of the list. PLCombine(3) has certain limitations with regard
to the way in handles color and normal data; see its manual page for details.
When vector objects are switched into polylists, they are transformed into polygons with two vertices. The faces of the polygons are the
same color as the given vectors, but the edges of the polygons, which are their only visible aspect, have no color.
SEE ALSO anytopl(3), geomview(1)AUTHOR
Celeste Fowler
The Geometry Center
Geometry Center November 2 1993 anytooff(1gv)
Check Out this Related Man Page
POLYMERGE(1gv)POLYMERGE(1gv)NAME
polymerge - merge coincident vertices, collinear edges, coplanar faces in an OOGL OFF object
SYNOPSIS
polymerge [-v vertex_thresh] [-e edge_thresh] [-f face_thresh] [-V] [-E] [-F] [-d] [-b] [inputfile.off]
DESCRIPTION
Polymerge eliminates redundancies from polyhedral objects in OOGL's OFF format, and writes another OFF object to its standard output.
(Optionally it can produce instead an input file for Brakke's Evolver.) Specifically, it combines nearly-coincident vertices, nearly-
collinear edges, and nearly-coplanar faces. Vertices which aren't used on any face are deleted, as are faces with less than three ver-
tices. Thresholds for approximate equality are adjustable from the command line. Options are:
-v vertex_thresh
Merge vertices when they're closer than vertex_thresh apart; the default is .00001.
-V Don't attempt to merge vertices.
-e edge_thresh
Merge edges where |sin(vertex_angle)| < edge_thresh; the default is When edges are merged, the corresponding vertex is removed.
-E Don't attempt to merge edges. (4OFF edges are never merged.)
-f face_thresh
Merge faces sharing an edge where the faces are nearly coplanar: when |sin(angle_between_face_normal_vectors)| < face_thresh. The
default is .03, or about two degrees. Note that merging can create faces which are concave polygons.
-F Don't attempt to merge faces. (4OFF faces are never merged.)
-b Produce an output file in .fe format for Brakke's Surface Evolver, instead of a new OFF file.
-d Include debugging information as comments in the new OFF object. The comments indicate which vertices and faces in the original
object correspond to which in the new one. Messages include:
# Vtx nnn->mmm
Merged vertices nnn and mmm (both indices in the original object).
# Merged face nnn into mmm (vertices vvv www) n1.n2 s
Faces nnn and mmm in the original object were merged; their common edge joined original vertices vvv and www. The cosine of the
angle between the face normals was s.
vertex coordinates # newvertno [order] # oldvertno
Each vertex written appears with its new index, its order (number of edges touching that vertex), and its old index (index of a cor-
responding vertex in the original object).
face description # oldvertno ...
For each new face, with N vertices after reduction, the comment indicates N corresponding vertices in the original object.
AUTHOR
Stuart Levy, Geometry Center, University of Minnesota
SEE ALSO anytooff(1), offconsol(1)BUGS
Coplanar faces are merged even if they were assigned different colors. Should be able to handle binary OFF objects, but this hasn't been
tested.
Geometry Center 25 July 1993 POLYMERGE(1gv)