Name

rthide — ray-traces a model and writes a hidden line removed UNIX-Plot file.

DESCRIPTION

Rthide operates on the indicated objects in the input model.g and produces a hidden line removed UNIX-Plot file with bas-relief features. rthide produces plots by drawing a boundary whenever a change in region_id is detected. It also recognizes and portrays abrupt changes in surface curvature and changes in surface height. This permits the recognition of pits, protrusions, and changes in surface curvature.

The orientation of the rays to be fired may be specified by the -a and -e options, in which case the model will be autosized, and the grid will be centered on the centroid of the model, with ray spacing chosen to span the entire set of objects. Alternatively, with the -M option, a transformation matrix may be provided on standard input which maps model-space to view-space. In this case, the grid ranges from -1.0 <= X,Y <= +1.0 in view space, with the size of the grid (number of rays fired) specified with -s This option is most useful when rthide is being invoked from a shell script created by an mged(1) saveview command.

The following options are recognized.

-s#

Number of rays to fire in X and Y directions (square grid). Default is 512 (512x512).

-a#

Select azimuth in degrees. Used with -e and conflicts with -M

-A#

Select angle for shading. Default is 5.0 degrees. 89.0 will produce a plot where only steep drops and rises are shaded.

-e#

Select elevation in degrees. Used with -a and conflicts with -M

-M

Read model2view matrix from standard input. Conflicts with -a and -e

-g#

Select grid cell width.

-G#

Select grid cell height. If not specified, cell height equals cell width.

-U #

sets the Boolean variable use_air to the given value.

-o

output.pl specifies a named file for output. By default, the plot is written to hide.pl.

-x#

Set librt debug flags to (hexadecimal) number.

The rthide program is a simple front-end to librt(3) which is most useful when used with mged(1).