Brush mode indicator

[GoogleCodeExporter]

The top-left button displays a special icon when the current paintbrush is
"user brush".
I propose that this button displays a different icon when the user brush is
in monochrome mode.
Since that's the icon you right-click to enter "monochrome mode", it will
be a way to give some feedback to the user. When you exit monochrome mode
(by right-clicking the "grab brush" icons), the top-left icon should update
too.

An easy thing is to draw a black silhouette of the original icon: this
doesn't need any change in skin files.
Otherwise, we need think of a specific icon design. Note that several skins
have different icons.

For future expansion, think we may eventually want a third icon: brush in
opaque mode.

Original issue reported on code.google.com by yrizoud on 28 May 2010 at 10:30

[GoogleCodeExporter]

Mostly done in r1495 and r1496

Original comment by yrizoud on 7 Jun 2010 at 12:04

• Changed state: Started

[GoogleCodeExporter]

Looks like it's done.

Original comment by pulkoma...@gmail.com on 2 Aug 2010 at 11:11

• Changed state: Fixed

[GoogleCodeExporter]

I still think it would be nice if right-click on the paintbrush button when in 
"monochrome mode" would restore the userbrush (which now requires a right-click 
on the brush-grab button).

Original comment by annas...@hotmail.com on 2 Aug 2010 at 12:55

[GoogleCodeExporter]

Ah yes... noticed that while testing the changes. Would you mind opening a 
spearate ticket ? It's slightly unrelated :)

Original comment by pulkoma...@gmail.com on 2 Aug 2010 at 12:58