Following the popularity of the AutoTrace plugin, we received a number of requests for additional features and to incorporate the tool into the main Advanced Digitising tools in QGIS.
Funding for the work was generously raised with the help of the community in 2015 and the feature landed in QGIS 2.14
Check out the Trace Digitising in QGIS for detailed instructions on how to use the tool.
The trace tool:
The following video demonstrates how to use the tracing tool:
This video shows how you can make use of tracing while reshaping a polygon:
The project was kindly sponsored by the QGIS community. Special thanks to all those who contributed towards the development of this tool: