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

[Garth Fletcher]

Hi Nathan,

I typically work with a 1-button mouse or a stylus, so I don't have a
mouse wheel. I didn't know about the Page Up/Down, thanks for that tip!

Other navigating modes are by no means a high priority item. QGIS is a
spectacular program and is entirely useable as is.

The (minor) advantage of modifier-key driven shifts from cursor to pan
(hand) to zoom-in or zoom-out is that it allows one to maintain focus on
the image / cursor position while performing all the normal navigation
steps.  Those accustomed to working in Photoshop or similar programs
develop habits - one hand on the mouse/stylus, the other manipulating
the modifier keys - which provide for a very smooth work flow.

Another advantage is that zooming can be set to center on the cursor
position - in effect combining a zoom with pan - which also helps
maintain focus on the area of interest.  I have not yet checked if
Page Up/Down uses current cursor position to define the new center, but
it may.

I am sure there are many many much more important additions in progress,
but sometimes just having a concept "in the stack" makes it possible
to add a nice feature with little effort when working on something
more important in the same source code area...

Cordially,
Garth Fletcher
Mason, NH 03048

Nathan Woodrow wrote:
> Hi,
> 
> In QGIS:
> 
> Space + move mouse is pan
> Middle click mouse is always pan
> Mouse wheel is always zoom.
> 
> Page Up/Down = Zoom In/Out
> 
> Not sure we need any other methods at this stage.
> 
> Regards,
> Nathan
> 
> On Sat, Apr 16, 2016 at 12:49 AM, Garth Fletcher <garth at jacqcad.com 
> <mailto:garth at jacqcad.com>> wrote:
> 
>     The approach I'm used to is widely used in Mac software, such
>     as Photoshop.
> 
>     It allows one to dynamically navigate using the following key
>     combinations:
>      space bar with click & drag : pan (i.e., "hand tool")
>      space bar + Command key with click : zoom in centered on cursor
>      space bar + Option key with click : zoom out centered on cursor
> 
>     It makes it very easy to navigate within an image.  In most
>     software it also changes the cursor shape to provide feedback
>     as to its current mode.
> 
>     One could use the Alt or Control keys on other systems.
> 
>     In QGIS I've instead defined custom keystrokes to select the
>     3 tools - +mag, -mag and pan - but that is less efficient as
>     it requires the extra keystrokes.
> 
>     Cordially
>     -- 
>     Garth Fletcher
>     Mason, NH 03048