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.

GRASS requires proj, gdal, numpy and wxPython.

The following optional dependencies may be enabled:
  blas
  lapack
  geos
  ffmpeg
  mysql
  postgresql
  sqlite

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