Change the plot text so it receives a QPointF instead of x,y, and a Parent

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Fix some compiler warnings

Passing the alignment as int instead of float or double was actually a bug
as CENTER is defined as (-0.5) ...

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Implement the get_screen_dpi function

This is sadly known to be incorrect on most systems. But it's as incorrect
as it was on Gtk so should work equally well to get roughly the right
sizes for printing - once we implement printing, that is :-)

Also removed a qDebug that snuck in in commit 6fc4d72079dd ("Enable
defautl_filename in settings").

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Fixed Zoom and Positioning of the Ruler Items

The items are still being placed far from each other when
zooming in - I need a bit of help with the math for that.

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Fixed loading the first dive via command line on the profile.

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Make nextDC and previousDC work and assign shortcuts

Cursor right and left now work again to switch between divecomputers.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Crash fixed on clicking on the canvas while no dive is loaded.

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Merge branch 'fixCrash' of https://github.com/tcanabrava/subsurface into Qt
Merge branch 'fixCrash' of https://github.com/tcanabrava/subsurface into Qt