This is a repository for a webtrees module known as gvexport. GVExport's goal is to produce an "all in one tree" of every person in a family tree and their relationships.
Webtrees is an online collaborative genealogy application. It started life as PhpGedView but PGV has since had limited development. Webtrees was born as a fork of PGV after issues regarding using SourceForge arose.
The ouptut format of the module is known as DOT and is used by GraphViz which is a general pupose graphing tool. If GraphViz is installed on the server the module can use it to generate image files directly.
The original GVExport Module appears on the PhpGedView Wiki but the developer states he hasn't worked on the module in over two years and doesn't plan to any further.
pceres created a GitHub repository as a maintenance repository after the original developer's notice about ceasing development. However this module is still targeted at the stale PhpGedView. This repository is a fork of pceres' repository.
This module therefore is the missing piece of the puzzle. It is the updated version of GVExport based on pceres' latest developments but instead targeted at latest version of Webtrees.
Here is a sample of the type of graph which can be produced:
