search

qgis / QGIS

QGIS is a free, open source, cross platform (lin/win/mac) geographical information system (GIS)
https://qgis.org
GNU General Public License v2.0
10.37k stars 2.98k forks source link

Digitize on canvasPressEvent instead of canvasReleaseEvent #37119

Open jfbourdon opened 4 years ago

jfbourdon commented 4 years ago

Feature description. Several tools currently use canvasReleaseEvent during digitalization to mark a point/vertex on the canvas (i.e. Measure Line/Polygon/Angle and Add Point/Line/Polygon Feature ). I think it would be (slightly) better to use canvasPressEvent during digitalization as it would really put the point where the user clicked, which is probably where he wanted to. A shift can occur if the user keeps its left click engaged a bit to long while moving its mouse (even slighty) at the same time.

Not a huge deal, I agree, but it feels weird to don't have the feedback of the left click right away. Maybe there is a reason to explain the way it is now, I don't know.

nyalldawson commented 4 years ago

Agreed! I'm changing this to a bug

uclaros commented 4 years ago

The rationale behind using the canvasReleaseEvent is probably that some tools have a secondary action by supporting dragging, like the selection, zoom or vertex tool. Also, some people (usually older people though) move the mouse unintentionally while pressing the button, then they may realize they moved it, re-aim and release.