Posted by sand1024 on Dec 04, 2024; 6:27pm
URL: https://forum.librecad.org/Dimensions-tp5725567p5725756.html

well, I'm not sure it will be more convenient than current implementation of zoom - yet probably I can't imagine well how it may work.

You can take look rs_graphicview.cpp - and there are a set of functions related to zoom and scroll.
Plus, the starting point may be void QG_GraphicView::wheelEvent(QWheelEvent *e).

However, please note that there are lots of code related to zoom/pan, so quite a careful testing is needed if something is modified in that area - just to ensure that no unexpected side-effects or issues were introduced.  And it might be that it may be harder to implement such feature than it might be expected initially.