Bug report #22082
PostGIS closed circle in Curved Polygon is not displayed
|Affected QGIS version:||3.6.0||Regression?:||Yes|
|Operating System:||Windows10||Easy fix?:||No|
|Pull Request or Patch supplied:||No||Resolution:|
|Crashes QGIS or corrupts data:||No||Copied to github as #:||29895|
The way to store closed Circles in PostGIS differ from circular strings. Circular strings will have three points: start, end an third point somwhere on the arc. For closed circles the PostGIS documentation says: "The exception to this is for a closed circle, where the start and end points are the same. In this case the second point MUST be the center of the arc, ie the opposite side of the circle."
In QGIS 3.6.0 closed circles will not displayed at all, when following this definition. In QGIS 2.18.2 they are displayed correctly.
When digitizing closed circles in QGIS 3.6.0 they will have 5 points on the arc. Those circles are displayed in QGIS 2.18.2 and QGIS 3.6.0.
I have tested this with Curved Polygons. However probably the same behaviour will be with Circular Strings and Compound Curves.