GRASS GIS (https://grass.osgeo.org/) is a Geographic Information System used for geospatial data management and analysis, image processing, graphics/map production, spatial modeling, and visualization.

In general: you don't really need write access as you can simply open a pull request to contribute to GRASS GIS. See CONTRIBUTING file for more details.

Want to become a core developer? See Procedure for gaining Git write access

See INSTALL file.

Yes, you should really read INSTALL.

This needs doxygen (http://www.doxygen.org) and optionally Graphviz dot (http://www.research.att.com/sw/tools/graphviz/).

To build the GRASS programmer's documentation, run

make htmldocs

or to generate documentation as single html file (recommended for simple reading)

make htmldocs-single

here. This takes quite some time. The result is in lib/html/index.html which refers to further document repositories in

lib/vector/html/index.html
lib/db/html/index.html
lib/gis/html/index.html

The master file is: ./grasslib.dox where all sub-documents have to be linked into.

To generate the documents in PDF format, run

make pdfdocs

An online version is available here

Build using the downloaded source code (in the directory with the source code):

docker build -t grassgis79 .

A test run (assuming you have existing GRASS GIS location; it can be downloaded from here)

# case 1: launching in the grassdata directory in which the location is stored:
docker run -it --rm --user=$(id -u):$(id -g) --volume $(pwd):/data \
    --env HOME=/data/ grassgis79 grass --text nc_basic_spm_grass7/user1 \
        --exec g.region -p

# case 2: launching anywhere
docker run -it --rm --user=$(id -u):$(id -g) \
    --volume /your/test/grassdata/:/data --env HOME=/data/ grassgis79 \
        grass /data/nc_basic_spm_grass7/PERMANENT --exec g.region -p

Note that the first grassgis79 is the name of the image while the second grass is the name of the executable.

To run the tests (again assuming local location):

docker run -it --rm --user=$(id -u):$(id -g) \
    --volume /your/test/grassdata/:/data --env HOME=/data/ -w /code/grass \
        grassgis79 grass /data/nc_basic_spm_grass7/PERMANENT --exec \
            python -m grass.gunittest.main \
                --location nc_basic_spm_grass7 --location-type nc

Note: If you compiled locally before building the Docker image, you may encounter problems as the local configuration and locally compiled file are copied to and used in the Docker image. To make sure you don't have this issue, clean all the compiled files from the source code:

make distclean