OpenCPN general drawing plug in
Requires latest OCPN 5.x.x as it is using version 1.16 of the plugin API
More information about this plugin is avaiable from the OpenCPN user manual. You will find it here: https://opencpn.org/wiki/dokuwiki/doku.php?id=opencpn:opencpn_user_manual:plugins:safety:odraw1.6_pi