Bug 463433

Summary:	Mypaint brush size slider effects/shifts curves on multiple parameters
Product:	[Applications] krita	Reporter:	MarcKUser <mgboarder>
Component:	Brush engines	Assignee:	Krita Bugs <krita-bugs-null>
Status:	CONFIRMED ---
Severity:	normal	CC:	griffinvalley
Priority:	NOR
Version First Reported In:	5.1.2
Target Milestone:	---
Platform:	Microsoft Windows
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Curve shown shifted up

Description MarcKUser 2022-12-24 16:04:19 UTC

Created attachment 154808 [details]
Curve shown shifted up

https://krita-artists.org/t/mypaint-brush-bug-radius-logarithmic-size-curve-affected-by-basic-size/53913

I want to adjust things like size and smudge intensity with changes in pressure. I adjust the curve and it works but then if I adjust brush size on canvas using (shift + pen motion) and i see that the changes I made are shifted up, such that the highest point I made goes to the top.

I think the main issue is that Krita’s basic size slider needs to be swapped with the log radius algorithn found inside Mypaint Brush Engine while using mypaint brushes only of course. Because the one krita uses affects multiple paramaters inside the mypaint engine.

Comment 1 wolthera 2023-01-12 10:43:40 UTC

I can confirm with the Krita Version: 5.2.0-prealpha (git 5c98a72) Appimage with Qt 5.15.7

Reproduction steps:
1. Take "i) wet paint plus (mypaint)
2. go to Smudge
3. Lower the left most node on the curve so that none of the curve nodes touch the top.
4. Resize brush.
5. The Smudge curve is now moved so that the topmost node touches the top..

The feeling I am actually getting is that the max and min aren't being saved, but I'm not too intimately familiar