Allow zooming and panning during painting

[D Gowers]

Zooming and panning while painting allows to block out objects quickly with only a few strokes (and some keyboard assistance to change pen color).
At the moment, blocking out abilities are extremely broad only, and you need to add smaller details as a separate action after reducing brush size and zooming in. Being able to zoom in during painting would allow greater precision to allow the medium-size details to also be blocked out quickly, as part of the same single action.

When zooming, it would need to zoom in to the current area in such a way that the pointer's position within the window still makes sense (ie. if you were painting on a particular pixel before zooming, you would still be directly over that pixel after zooming.)

MyPaint supports zooming/panning when painting, so I was able to make a mockup demonstrating what can be done in very little time. The attached image of a traffic cone was drawn in 3 strokes (== pen down, pen up pairs):

Stroke one: Define the silhouette
Stroke two: Define the lighting (using keyboard to change palette color, and brush size)
Stroke three: Disconnect the bright band on the cone from the front of its 'foot'
(image shows breakdown of strokes)

[D Gowers]

For now, attachment seems broken, so I will just post the url of the demo image instead:

​http://i.imgur.com/YO9FcgH.png

[Adrien Destugues]

We already have the mouse staying on the same pixel when you zoom in/out (try the mousewheel), unless you are too close to a border and zoom out, because we don't allow the viewport to go further than the image border.

[D Gowers]

Yes, that's a good zooming behaviour (I admit I didn't realize it already satisfies my "stay on the same image pixel" criteria). I am suggesting that the ability to zoom as you paint would be an improvement. (this is easiest with a tablet, but it's still quite doable with a mouse).

In case that is not clear enough, I am talking about pressing down the pen or mouse button to draw, keeping it down and using the Zoom actions while the button/pen is still down. That allows you to block out most of an object in a single stroke.

The mousewheel does nothing, BTW.
Middle click and mousewheel have never done anything at all in GraFX2, for me.

Which is a shame, because IMO middle click really should pan the view, then we'd be consistent with the hundreds of other programs that use it to pan the view :) (and middle click panning is really comfortable, too, of course)

[PulkoMandy]

Move open tickets to 2.7 milestone