Very quick notes:

• in Kirta we paint with "dabs"
• all the painted dabs overlap with more than 80-90% of their area. Therefore, if we stop iterating pixels in a per-dab basis, but start grouping the dabs in sets of, say, 10, and calculate pixels for the united area, then we can get the gain up to 10x times.
• the blending of the opacity channel should also be simplified. Basic composite "over" is really slow, so we should use some "simplified" approach. This might be one of the topics of the scientific research.
• the main question of the research: can we use dynamically changing opacity for the strokes?

Our gradients have low quality. See comparison to Gimp in T678. It happens due to a number of reasons.

• we use caching in KisGradientPainter::paintGradient() see implementation of CachedGradient in the same class. It might happen that the amount of cache levels is not enough for painting smooth gradients and it should be made higher.
• we don't use any dithering algorithm for painting gradients. Basically, we need one more wrapper over CachedGradient which adds a noise of a specified distribution and size to the input value of cachedAt() or valueAt()
• you can find a unittest for this class in libs/image/tests/kis_gradient_painter_test.cpp

uhm, I made this brush.

For watercolor effects, all that Photoshop does is pass the stroke through a high-pass filter so you get the wet/dark fringes effect.

Watercolor support is 5/5, no matter what type of method you take because all existing papers are either CPU and slow, or GPU and... well, it's on the GPU, 'nuff said. Edit: Unless you are thinking of only a fringe efect, which is much smaller.

2. Gradients
   • Priority: high
   • Level: 1/5
   • Time to code: ~1d

https://bugs.kde.org/buglist.cgi?bug_severity=wishlist&bug_status=UNCONFIRMED&bug_status=CONFIRMED&bug_status=ASSIGNED&bug_status=REOPENED&component=filters&list_id=1353135&product=krita&query_format=advanced

15:25 < boud> https://bugs.kde.org/show_bug.cgi?id=347920
15:25 < bugbot> KDE bug 347920 in krita (Brush engine) "Edge sharpening for circle brush tip (watercolor-like effect)" [Wishlist,Confirmed: ]
15:25 < boud> https://bugs.kde.org/show_bug.cgi?id=348308
15:26 < bugbot> KDE bug 348308 in krita (Brush engine) "Wash mode for dulling smudge brushes" [Wishlist,Confirmed: ]
15:26 < boud> https://bugs.kde.org/show_bug.cgi?id=344108
15:26 < bugbot> KDE bug 344108 in krita (Brush engine) "Feathering option for Experiment brush" [Wishlist,Confirmed: ]
15:26 < boud> https://bugs.kde.org/show_bug.cgi?id=335180
15:26 < bugbot> KDE bug 335180 in krita (Brush engine) "Extend expriment brush with outline mode." [Wishlist,Confirmed: ]
15:26 < boud> https://bugs.kde.org/show_bug.cgi?id=319446
15:26 < bugbot> KDE bug 319446 in krita (Brush engine) "Use SVG brush file as shape library for animated brush. (Alchemy pull shapes feature)" [Wishlist,Confirmed: ]
15:26 < boud> https://bugs.kde.org/show_bug.cgi?id=315079
15:26 < bugbot> KDE bug 315079 in krita (Brush engine) "Idea: add textures for experiment brush" [Wishlist,Confirmed: ]
15:27 < boud> https://bugs.kde.org/show_bug.cgi?id=358183
15:27 < bugbot> KDE bug 358183 in krita (Brush engine) "Feature request: support randomness/rotation in clone brush engine" [Wishlist,Confirmed: ]
15:28 < boud> https://bugs.kde.org/show_bug.cgi?id=349459
15:28 < bugbot> KDE bug 349459 in krita (usability) "Improvements for the reference image docker." [Wishlist,Confirmed: ]

1. Create a fill layer filled with a color
2. Image->Resize Canvas. Resize the image up to 200%

[new string, for Krita 3.1] https://bugs.kde.org/show_bug.cgi?id=349458 Add workspaces as submenu in the window menu
https://bugs.kde.org/show_bug.cgi?id=358673 Wish: show previous color in color selector
https://bugs.kde.org/show_bug.cgi?id=349152 When transforming a clone layer with transform tool, create a transformation mask automatically
[renames, for Krita 3.1] https://bugs.kde.org/show_bug.cgi?id=352533 Add quick flip buttons to transform docker
[UIX design needed, for 3.1] https://bugs.kde.org/show_bug.cgi?id=143306 when moving the image block, show always (!) coordinates
[UIX design needed, for 3.1] https://bugs.kde.org/show_bug.cgi?id=349048 List of available tag in drop down is to short in height
[UIX design needed, for 3.1] https://bugs.kde.org/show_bug.cgi?id=333462 A tool that crops canvas by pixel colour

The look is pretty okay now after Scott's latest edits.'

Okay, looking about there's a few places where we could want dithering to improve gradients, all of these should be optional:

Should be fixed in https://phabricator.kde.org/rKRITA90f92507e15b

yes , I experienced this now

The bug is still actual. On Linux on both Qt 5.5 and Qt 5.6.

I'm wondering how "Creation of a selection" can remove nodes? As far as I know it can only add a selection mask. It can also remove it (Deselect) if you just click on the canvas. But still I cannot reproduce the bug :(

for me this doesn't happen anymore in 3.0 , this was fixed by @dkazakov with this commit - > 5f35f4463534c9c1b21a37a43c50cc1ea0f498aa

yeah, getting that one commonly as well... I am suspecting this only happens on development versions, so lowering the severity.

I'm trying to reproduce this bug, yet without success.
But I got this message once while animating:

Yeah it seems color picking got mystically fixed in the past week. Maybe it's due to QT 5.6 release?

I can't reproduce this in 3.0 , for me color picking while holding ctrl key works fine.

confirmed. The difference is between clicking on the canvas and clicking on a different layer.

yes this still happens to me .

this only happens in development versions, btw.

can' t confirm. Can you check again @kamathraghavendra

I have two PSD files that contain groups that Krita refuses to load.

Seems that I fixed all the problems

Can't make it not to go out of color selector.

I checked your patch and it looks really good! There is one blocker bug still. If you press a mouse button, move the mouse out of the widget and then release the button, the widget will end up in an inconsistent state. I added a comment about how to fix that. The other comments are just styling nit picking :)

You should add reviewers too :)

At the moment we can't copy and past berween frames (not entire frame but parts of it), it creates new Layer as usual in 'paint mode' .
We can have another shortcut for this operation (ex. Ctrl+Shift+V)

Seems like a duplicate of Space + drag not working multiple times

resolved by clean install... cmake must've been confused.

Yes, fixed now!

This should be complete now, yes?

I just pushed the diff out to the 'krita-layers-gui-kazakov' branch

Looks fine now! :)

made the updates. I made the text a bit more visible on the layer. I also did the save/restore pattern for the opacity. Cleaned up the random new line changes that were not needed.

I like the idea of your patch. We should do it in a way you suggested. But there are a few small issues:

yes, though I didn't see this task before, and dmitry only asked me for 12px icons, so there is no special version for HI-DPI for now.
Though since we don't have such HI-DPI version for any other icon, I think we can close it.

@timotheegiet, @dkazakov , this was done, yes?

well, then.

Er... It was always the layer view's delegates that forced the width to a particular size. In any case, I have always said, and still say, that his is about the lowest priority task there is.