SUMMARY This feedback is a request to have future versions of Krita to render the canvas in real-time without glitches for all possible operations like the one you see in the video attached. ADDITIONAL INFORMATION : I use Krita 4.3.1 alpha stable build on Windows 10 1909 currently.
Created attachment 129686 [details] glitchy_rendering
Real-time? you are asking too much for current technology. Performance is one of our top priorities so we do have some plans already laid out on how to improve speed on filter rendering to allow a faster rendering. As it is the canvas is rendered in a tiled way to avoid any delay, as if you change the filter settings mid renering it can cancel the tiles not yet processed. Without tiles you would need to wait for your entire image to be processed with the filter for the operation to be shown, which in turn would be very slow. As long as the different tiles are not baked in the final applied result I would mark this as an invalid bug. You can reopen only if the filter is applying the glitches onto your image.
(In reply to vanyossi from comment #2) > Real-time? you are asking too much for current technology. Performance is > one of our top priorities so we do have some plans already laid out on how > to improve speed on filter rendering to allow a faster rendering. As it is > the canvas is rendered in a tiled way to avoid any delay, as if you change > the filter settings mid renering it can cancel the tiles not yet processed. > Without tiles you would need to wait for your entire image to be processed > with the filter for the operation to be shown, which in turn would be very > slow. > > As long as the different tiles are not baked in the final applied result I > would mark this as an invalid bug. You can reopen only if the filter is > applying the glitches onto your image. Greetings again. OK. Actually, that's what I want : bake the final result of the tiled parts before displaying/previewing the changes on the canvas. I understand that you have plenty of optimizations in the TODO list of your roadmap. But at least, do you get the idea ? If needed, I'll make another gif/video to show the behavior I'm looking for. Just let me know.
I think the problem is in the tiled flickering when updating the filter configuration. We have special code to avoid that in KisFilterManager, but for some reason it doesn't solve the issue for long filters (perhaps, because of need-rects, which gets updated accidentally as well?). So that is actually a bug :)
Upgrade to a minor bug
The bug should now be fixed in https://invent.kde.org/graphics/krita/-/commit/029deeef867866d744889a6150da2a372c4c3e6f