Re: [Gimp-developer] [Demo] Porting MyPaint brush engines to the GIMP.

[Tobias Oelgarte <tobias oelgarte googlemail com>]

Am 01.05.2012 11:25, schrieb David Gowers (kampu):
> > I also don't think GIMP's brush interface is perfect. It's a lot better
> > than it used to be, but it's still not very streamlined.
> Yes, they both suffer from the difficulty of providing ready access to
> all those different curves. Even though the MyPaint approach of
> showing all the curves for an output at once is greedy of screen
> space, I find it more usable than GIMP's one-curve-at-once approach.
In MyPaint you don't need to access the advanced brush editor very 
often. You have a lot of good presets and all you need to do is to 
adjust two or three settings, which have hotkeys and are easy to reach. 
For the user it means that he doesn't have to bother much about all this 
amount of settings. If wanted, then he can fine tune them, otherwise the 
provided brushes are already very sufficient for most tasks.

In Gimp on the other hand you don't have such presets and you start 
every time from scratch to design the brush again and again that you 
used previously. An excellent way to kill time without progress and 
desired result. :-(

It's not about the settings of the brush itself, it's about reusing 
brushes and their corresponding settings. For example: I use a knife to 
add color to a painting, then i use a knife without color to refine 
details and then i use the knife with color again. Switching between the 
two brushes can be done in MyPaint with one click or hotkey. But what 
will you do in Gimp?
> > It's for sure true that painting in GIMP is slower than it used to be.
> > Clearing the Undo History every now and then gives a dramatic speedup,
> > at least with the older 2.7 preview I'm using, and profiling suggests
> > there's an O(n^2) list insertion going on, although it's hard to
> > understand why that shouldn't be a matter of microseconds, not a
> > noticeable fraction of a second.
> Yes, GIMP is definitely weak compared to MyPaint WRT both painting
> performance and painting quality/ expressiveness.
So sad, but true.
> > The gimp brush outline rendering-in-the-idle-loop also makes painting
> > _feel_ much slower than it is.
> I'd still like it if we could get some kind of very simplified outline
> drawing. (say, 8 points -- the most distant pixels from the center
> where alpha>  threshold, along each of the right angles and 45degree
> diagonals). Then, we could use the simplified version during drawing,
> and the full version during 'hovering' (before the button is
> depressed)
Good idea. That the brush circle is so sloppy really irritates from 
drawing, not seeing where you really are.
> > I remember dealing with this in the past in another application by
> > discarding motion events if the pointer got too far behind. It meant
> > that the drawing became less accurate, but once the pointer outline
> > isn't where you're drawing, there's no accuracy in any case.
> .. Is that really true? (eg. with a tablet)
It will be delayed, but the curve will contain all dots. The main 
problem for painting is performance. If it isn't very responsive then 
you don't have a good feeling what is going on. Especially with a tablet.