Let me say first: I make this because I believe in Krita and I believe in it's potential.
For a "Free" application it's quite good. But just because it's free doesn't mean it can't be one of the best. Just like Firefox, for long time it's been free, and one of the best.
So, I've made 2 videos to show my frustration with 2 very simple operations compared to Photoshop.
I'm not a programmer coder so I have no idea what causes this lag.
You can see that Krita keeps working even while the canvas is processing the operation: I can click on the menus, mess up with the color handler and stuff. It feels like the canvas is handled by another process and renders the picture with a queue of commands and calculations.
Both videos are on the same canvas size: A3 600ppi
My system: Win 10, i5 2.7, 8GB, onboard graphics (for now)
Again, this is BASIC function, please don't say I need an i7 or a fat GPU.
Thanks.
https://youtu.be/XH4iwrrkFCw
https://youtu.be/PdSq1KqSnto
(these videos are not public, it's just for he dev team)

Did you try the checkbox "fast mode" in tool option with the fill tool ?
It's not activated on your videos. Fill tool in Krita is probably slower, but it can : grow fill , feather it.
Did you try with "Instant Preview" OFF and ON ? ( in menu > View ) for painting ?

Did you try it? Works fast for you?

For me, Fast mode on: slightly faster, but pretty much the same.
Yes yes, instant preview was off.

Did you try it? Works fast for you?

Yes, but I have another hardware and system: Processor : Intel i7 CPU 870 , 2.93GHz × 8, Memory : 16GB, GPU : GeForce GTX 650 Ti, system: Linux Mint 18.1 XFCE with Krita 3.1.2.
So it's smooth on my side, even for a A3 at 600ppi and your test: http://www.peppercarrot.com/extras/foru ... 600dpi.gif

I think there is still some lag there, after the 3rd blue click. What happens after 20 clicks with the same color in different spaces?

I can't afford an i7, so, if it is possible in Photoshop, even on i3, why not with Krita?

I started digital painting around the year 2000, and I would say it's a very acceptable lag for A3@600ppi for your hardware. ( usecase for A3@600ppi are also rare, imo, but that's another topic... )

if it is possible in Photoshop, even on i3, why not with Krita?

Because coding a digital painting application is something hundred time more complex than what you probably think it is. Also, the two projects are different and uses different code language and different technologies. Photoshop started in 1988, optimizing the core incrementally over 30 years with teams of hundreds of developers and probably 1000 time more budget than Krita for research and optimization. Windows development for Krita started in 2012. Only in the last year Krita went threw major changes: a port to a newer code framework ( Qt5 ), a split from the office suite Calligra and a refactor of the viewport to handle multi-documents. Also, on a hardware level ; even the driver of your tablet, your graphic-card driver or the display manager of Windows were probably tweaked by developers to work faster for Photoshop, office suite and games ( or the reverse; Photoshop optimized for specific hardware and proprietary API, and this incrementally over the years). The Krita team is a core of less than 5 developers ; with probably not more than two of them working full-time and managing all crowd-funding, communication, bug-tracking, community-answer, etc... They also propose you to use and install Krita for free and share the source code if you want to read or do modification.

It's a totally different project and you 'll build only frustration if you keep comparing them.

If you look for most performant solution on Windows for the task you demo on video: then choose Photoshop, no struggle here. You'll be always welcome to test Krita later over the year, and maybe the team will catch up with performance at a point. But a forum post like you did will not change anything for next week, next month or next version. It's something on the core, deep in the codebase and will needs hundreds of mini optimizations, workarounds, and tricks to be probably as performant as Ps can do now. Be sure developers of Krita constantly do the max they can to make this optimization, the focus and priority is really high on this topic. The proof; last features over the last year 'Instant preview mode' and the brush engine 'Quick Brush' were done to boost performances...

But a forum post like you did will not change anything for next week, next month or next version. It's something on the core, deep in the codebase and will needs hundreds of mini optimizations, workarounds, and tricks to be probably as performant as Ps can do now. Be sure developers of Krita constantly do the max they can to make this optimization, the focus and priority is really high on this topic.

Easy friend...

Yes, I don't expect that my post will change everything.

As I have previously said, I have big expectations for Krita, IT IS very powerful.
My post was just to point this issue.
I didn't know if the Devs are aware of this issue or not, they probably are, but I thought it didn't hurt to point it out.
I'm really sorry if I sounded rude or demanded a quick fix for that.

And as for digital painting, I started with Corel Photo Paint (7 I think) using a mouse, before tablets existed, almost 20 years ago. So, tell me about slow computers and software limitations.

Krita is designed to allow you shooting yourself in the foot, so the problem will always be there if you get creative enough.

Corel Photo Paint didn't exist 20 years ago. You must be thinking of Jasc Paintshop Pro. Tablets also existed back then, btw.

TheraHedwig wrote:Krita is designed to allow you shooting yourself in the foot, so the problem will always be there if you get creative enough.

Corel Photo Paint didn't exist 20 years ago. You must be thinking of Jasc Paintshop Pro. Tablets also existed back then, btw.

LOL

as for Photo Paint according to wikipedia it started 25 years ago, forgive me for not remembering accuratelly, it's been quite some time, but I remember that in my teens I was trying to make colors like Battle Chasers and Spawn.
https://en.wikipedia.org/wiki/Corel_Photo-Paint

And the tablets I mentioned in terms of availability, they were not popular much less compatible with current apps. I bought my first tablet around 17 years ago, and I needed a friend to bring it from USA because it was too expensive to import to Brazil.

@TheraHedwig: Haha for the foot. But objection for Photopaint! raphaelcatossi is right on this point and I can proof! Here is my work on Corel Photopaint , exactly 20 years ago. For context: I was 16y/o.. a scanner by then cost the price of a motorbike, and let's not talk about my pentium100 computer... No internet too, no tablet and I never saw digital artwork else than on video games ( Nintendo64 or Playstation1 ). As you can see: I was fond of the procedural texture generator and I had no idea about what mean 'anti-aliasing'