GRASS (Geographic Resources Analysis Support System) is a free Geographic
Information System (GIS) used for geospatial data management and
analysis, image processing, graphics/maps production, spatial modeling,
and visualization.  GRASS is an official project of the Open Source
Geospatial Foundation.

The following optional dependencies may be enabled:
  blas, lapack   for the GRASS gmath library
  ffmpeg         for the GRASS ogsf library and nviz animation
  mysql          for mysql (or mariadb) database support
  postgresql     for postgresql database support
  sqlite         for sqlite database support

The options you require must be specified by setting the variable ENABLE
before running grass.SlackBuild, for example

  ENABLE="sqlite,ffmpeg" ./grass.SlackBuild

If you need to make grass libraries available to other applications (e.g.
qgis) do this:

  echo /opt/grass/lib >> /etc/ld.so.conf && ldconfig