Is there a method where I can detect if a polygon is inside the concave area of another (in this case a bay), then output the bay itself?
It's hard to explain with words so I'll demonstrate below:
This polygon falls within a bay area and I want QGIS to make this bay area a new shapefile like below:
Is it possible that this can be done? The output would be part of a model where I am trying to measure the shortest line distance between two polygons, taking into account the shape of the coastline using the v.net.visibility GRASS tool, but simply running this model taking the whole of the British Isles coastline into account takes up too much processing power.