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.\" RCSid "$Id: obj2rad.1,v 1.4 2007/09/04 17:36:40 greg Exp $" |
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.TH ROBJUTIL 1 3/31/20 RADIANCE |
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.SH NAME |
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robjutil - operate on Wavefront .OBJ file |
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.SH SYNOPSIS |
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.B robjutil |
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[ |
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.B +/-r |
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][ |
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.B +/-v |
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][ |
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.B +/-t |
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][ |
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.B +/-n |
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][ |
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.B "+/-m mname" |
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][ |
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.B "+/-g gname" |
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][ |
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.B "-c epsilon" |
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] |
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[ |
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.B input.obj .. |
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] |
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.SH DESCRIPTION |
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.I Robjutil |
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reads and manipulates a Wavefront .OBJ file, removing degenerate and |
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duplicate faces. |
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If the |
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.I +r |
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option is specified, a Radiance scene description |
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will be produced on the standard output. |
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If |
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.I -r |
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is given, a modified .OBJ file will be sent to the standard output. |
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This is the default, and is |
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typically more useful, since surface normals are better handled by the |
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.I obj2rad(1) |
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and |
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.I obj2mesh(1) |
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converters. |
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The latter also preserves local texture coordinates for mapping materials. |
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The |
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.I +v |
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option turns on verbose progress reports. |
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.PP |
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The |
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.I \-t |
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option tells |
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.I robjutil |
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to remove texture coordinates from the input. |
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The |
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.I \-n |
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option will cause all surface normals to be removed. |
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.PP |
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The |
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.I "\-m mname" |
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option tells |
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.I robjutil |
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to remove all faces that use the material |
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.I mname. |
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Multiple |
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.I \-m |
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options may be given, each with a single (unique) material name. |
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Alternatively, the |
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.I "+m mname" |
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option may be used to specify a material one wishes to keep, discarding the rest. |
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Multiple |
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.I +m |
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options will keep all the named materials. |
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The |
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.I \-m |
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and |
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.I \+m |
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options are mutually exclusive. |
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Similarly, the |
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.I "\-g gname" |
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option says to remove all faces belonging to the group |
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.I gname, |
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and multiple |
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.I \-g |
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options may be given. |
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There is also a |
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.I +g |
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option to save just the named group(s). |
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.PP |
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Finally, a |
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.I "\-c epsilon" |
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parameter may be given to coalesce vertices that are within the given epsilon. |
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This is useful to improve the connectivity of models that were produced |
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in a sloppy conversion process from independent polygons. |
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When producing a Radiance file via the |
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.I +r |
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option, there will be no savings in the output size, but there can be |
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a benefit in reducing the number of "cracks" in the resulting geometry, |
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at least for triangle mesh input. |
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.I Robjutil |
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does not attempt to break up non-planar polygons into triangles, |
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which is usually not a problem for .OBJ output, but may be for Radiance |
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scene descriptions (+r). |
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.SH EXAMPLES |
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To remove degenerate and duplicate faces from "orig.obj" and write to "final.rad": |
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.IP "" .2i |
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robjutil +r orig.obj > final.rad |
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.PP |
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To convert the same file, preserving surface normal interpolation: |
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.IP "" .2i |
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robjutil orig.obj | obj2rad > withnormals.rad |
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.PP |
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To extract only the groups "cat" and "bell" from the file "kitty.obj" and |
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write to a Radiance triangle mesh using materials from "kitty.mat": |
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.IP "" .2i |
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robjutil +g cat +g bell kitty.obj | obj2mesh -a kitty.mat > kitty.rtm |
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.SH AUTHOR |
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Greg Ward |
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.SH "SEE ALSO" |
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obj2mesh(1), obj2rad(1) oconv(1), xform(1) |
