STL-G(1)

NAME
bot_shell-vtk - VTK polydata converter (BRL-CAD to VTK)

SYNOPSIS
bot_shell-vtk [-m] [-n] [-d debug_level] [-g cell_size] -o vtk_polydata_output brlcad_database.g object1 [object2 object3 ...]

DESCRIPTION
Bot_shell-vtk uses raytracing to extract the exterior triangles from a model made up of BOT primitives. The default operation is to fire a single ray at each triangle of each BOT primitive in the specified objects. The rays are fired anti-normalward towards the center of each triangle from outside the model bounding box. If the triangle currently under consideration appears as the first object hit along the ray, then that triangle is included in the VTK polydata output (thus retaining only exterior triangles). Non-BOT primitives ancountered along the rays may hide BOT triangles, but non-BOT primitives do not contribute to the output. The -m option may be specified to enable both the first and last triangles along each ray to be added to the output. This can improve performance, by reducing the number of rays fired, but may reduce performance for complex models because it requires processing each ray completely through the model. If the -n option is specified, the the output will include vertex normals in the VTK output. If the BOT primitives of the input BRL-CAD model do not have vertex normal information, this option will not add any information to the output, but will greatly increase the size of the outout file. If the -g option is specified, then the rays are fired from a uniform grid for three orthogonal directions rather than at each individual triangle. This can give a fairly rapid result for larger cell sizes, but is likely to miss some triangles. The cell_size must be specified in millimeters. The -d option may be used to get debug output during processing. This is likely to only be useful for developers.

EXAMPLE
    $ bot_shell-vtk -o output.vtk sample.g the_exterior

DIAGNOSTICS
Error messages are intended to be self-explanatory.

AUTHOR
John Anderson

SOURCE
SLAD/BND/EAB Advanced Computer Systems Team
The U. S. Army Research Laboratory
Aberdeen Proving Ground, MD 21005

BUG REPORTS
Reports of bugs or problems should be submitted via electronic mail to <devs@brlcad.org>.