Bug report #12152
Consider point rotation for rotated maps
|Affected QGIS version:||master||Regression?:||No|
|Operating System:||Easy fix?:||No|
|Pull Request or Patch supplied:||No||Resolution:|
|Crashes QGIS or corrupts data:||No||Copied to github as #:||20345|
Rotated symbols that have a data-defined rotation field or are rotated with "Symbology -> advanced -> rotation field" need to be treated similar to manually placed fonts.
A cadastral map with a symbol indicating the flow-direction of a river. See attached image at angle 0. If I rotate the map, the arrow symbol should still correctly indicate the flow-direction of the river - but with the current behaviour it stays at the original rotation value (see screenshot at 45 degree angle).
There may be some cases where the symbols shouldn't be rotated with the map, but I think in most cases you want the symbol to be rotated as well. Maybe, for a future QGIS version, there needs to be an option whether the symbol should be rotated with the map or not. For now we would just add the map rotation to the symbol rotation as well.
#2 Updated by Sandro Santilli over 4 years ago
Related commit (fix for manually-placed labels): https://github.com/strk/QGIS/commit/297c30da805115c9b7a4592f295c6da4fc55373b
#5 Updated by Andreas Neumann over 4 years ago
Do you mean for "marker lines"?
I don't know. I have not tried. I usually use the "auto" rotation of markers at a marker line - which is probably what covers 99% of the use cases. In the "auto rotation" scenario, the markers are rotated perpendicular to the line at segments and according to the bisector angle at vertices (I think).
#6 Updated by Sandro Santilli over 4 years ago
I mean for markers you apply to lines. For example arrows at the first or last point of lines.
There seem to be an additional option in that case, which is "rotate" symbol. With "rotate" the marker is rotated following the line orientation, otherwise it isn't. In any case the Advanced->RotationField seems to do nothing.
#7 Updated by Andreas Neumann over 4 years ago
Ok - got it. It is probably a bug if it isn't working. But then I don't see a use-case why one wants to completely rotate a line.
It is probably a bug that this option is still available for line or polygon geometries.
I thought there was a pull request to remove these advanced options, because they are also available now at the symbol level.
In my opinion, this rotation option only makes sense for point data.