[Qgis-user] shift or control to toggle zoomin/zoomout?

[John Layt]

On 14 April 2016 at 20:14, Richard Duivenvoorde <rdmailings at duif.net> wrote:
> Hi,
>
> Most drawing programs (like inkscape) have one zoom tool, which toggle
> between zoomin/zoomout with ctrl or shift button.
>
> This looks like not so difficult to do? We could keep the two buttons as
> now, but also toggle them to the alternative temporarily when you push
> shift of control.
>
> Others think this is usefull?
> Or see problems?

I've always found the having 3 separate tools for basic navigation a
bit weird, switching seems a waste of time and mouse movement,
especially when you're interacting using other tools and need to
navigate without breaking your use of your current tool. While we have
mouse wheel scrolling in all tools, it's imprecise, so a set of
consistent keyboard modifiers that applied in all map tools would be a
good thing.

At work we've been experimenting with a single navigation map tool to
'do it all', currently:
* Left Click: Zoom in one step
* Left Click and drag: Zoom in to selected area
* Right Click: Zoom out one step
* Right Click and drag: Pan map canvas

That's in addition to the existing standard functions:
* Mouse wheel: Zoom in/out
* Space bar + mouse move: Pan map canvas

I've also been thinking about using ctrl to switch to selection mode.

The problem we're having is that this is a bit inconsistent with our
custom editing map tools where unmodified left/right click is
obviously for drawing or feature interaction, so we move the zoom to
the shift button. We could make the navigation tool consistent by
moving zooming to the shift button too, but then what does an
unmodified click mean? Panning? Selection? Identify? Anyway, the point
is a set of standard modifiers would save me some code and give our
users a more consistent experience outside our own tools.

John.