This commit mostly removes unused code and cleans some things up.
The main contribution is that instead of calling repaint() and Refresh(), we
now only mark the canvas as dirty and call Refresh(), which will do the repaint
just-in-time. This speeds things a lot when quickly changing layers or zooming,
as it does not repaint once per keyboard/mouse event but once per actual
Refresh, which makes it much smoother.
FWIW, on my test system with my test GCode loading time goes down from 5.7s to
2.3s between b3a673bc97 and this commit, that's almost 60% gone.
However, there is still a lot of room for functional improvements :
- I don't think the roundtrip through the target array is useful
- There's no handling of relative coordinates (neither for position nor for e)
- The arcs drawing code might be wrong
- The stlview bits are not enabled and probably have to be looked at and updated
Guillaume Seguin