Bug 370604

Summary:	Deform Brush doesn't respect alpha
Product:	[Applications] krita	Reporter:	Leonardo Kaempf <monatsend>
Component:	Brush engines	Assignee:	Krita Bugs <krita-bugs-null>
Status:	RESOLVED WORKSFORME
Severity:	wishlist	CC:	griffinvalley, halla, monatsend
Priority:	NOR
Version:	3.0.1
Target Milestone:	---
Platform:	Microsoft Windows
OS:	Microsoft Windows
Latest Commit:		Version Fixed In:
Attachments:	Deform example

Description Leonardo Kaempf 2016-10-12 21:18:02 UTC

when using  the deform-brush on Lineart with transparent parts it only deforms the RGB-Data not the Alpha. 

The result is a blotch instead of a deformed line.

Reproducible: Always

Steps to Reproduce:
1. have some lines on transparent BG
2. Deform it with the deform-brush engine (doesn't matter which mode)
3. Result is not what expected

Comment 1 Leonardo Kaempf 2016-10-12 21:19:09 UTC

Created attachment 101548 [details]
Deform example

Comment 2 Halla Rempt 2016-10-13 09:21:46 UTC

Hm, the deform brush has always behaved like this, so I'm not sure it's a bug or the way Lukas designed the brush engine... The behaviour you're after is implemented in the liquify option of the transform tool.

Comment 3 Leonardo Kaempf 2016-10-13 09:34:24 UTC

Hi, 
I hope that its not the case, that it behave like this.
And I really dont think so.
why should this tool behave compleately different on transparent background than on opaque?

And the reason why I am using this Brush  is very fast to use. ?and maybe more performant?

In my case its fine when the image quality suffer from using the deformbrush, because mostly I use it in an early scetching state.

Comment 4 Halla Rempt 2016-10-20 14:21:01 UTC

Well, we might change it, but tbh, before we find a volunteer for hacking that code could take a longish time. Since this brush has always behaved like this, changing the behavior makes it a wish, not a bug.

Comment 5 wolthera 2016-10-20 17:21:25 UTC

This is what happens when you set the blending mode to 'normal'. If you use 'copy'(which the only default preset, 'move_tool' is set as), it works as expected.

Comment 6 Halla Rempt 2016-10-20 17:30:31 UTC

Ah, thanks! Then we can just close it.

Comment 7 Leonardo Kaempf 2016-10-20 20:59:16 UTC

Ok then. Thank you very much for the hint and sorry for the disturb.

Great software!