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

[Garth Fletcher]

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