Adding a new temporary scratch layer in QGIS, selecting the Geometry type, there are different options, between else MultiSurface.
In the documentation, I could not find any information about this Geometry type. What is the difference from MultiPolygon? As I understand it, a MultiPolygon is used to create features with several non contigent parts – like countries consisting of the mainland + islands (say Italy: the "boot"-shaped mainland + Sicily, Sardinia etc.). So what are MultiSurfaces for?
Best Answer
The OGC standard about Simple Features describes LineString and LinearRing
Polygons are made of LinearRings so it means that in a polygon all the segments are straight lines.
Curvepolygon is a geometry that allows also curved segments (arcs). Geometry that is combined from several Curvepolygons is called MultiSurface.
An example about the difference using the PostGIS function https://postgis.net/docs/ST_CurveToLine.html
Source geometry is a curvepolygon that could be an element in a multisurface:
Apply the PosGIS function ST_CurveToLine:
Resulting output: