Bug 361293

Summary: [WACOM] Airbrush wheel returning negative value and krita creates a negative brushsize
Product: [Applications] krita Reporter: Pierre "bloodywing" Geier <bloodywing>
Component: Tablets (tablet issues are only very rarely bugs in Krita!)Assignee: Krita Bugs <krita-bugs-null>
Status: RESOLVED FIXED    
Severity: minor CC: griffinvalley, halla, herrkjeldsen, osxyz, var.spool.mail700
Priority: NOR    
Version First Reported In: git master (please specify the git hash!)   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: http://commits.kde.org/krita/88f88fe7a432a0202db8dcba22f6b5f2e2d4868e Version Fixed In:
Sentry Crash Report:
Attachments: the patch basically does the same as we did in krita 2.9

Description Pierre "bloodywing" Geier 2016-04-01 21:53:52 UTC 
The Wacom Airbush Pen returns a integer (or float?) range with can be negative or positive

lowest value is -255 and highest +255.
The range 0 - 255 works just fine in krita but when I scroll further with the airbrush wheel it returns a negative number and krita increases the brush size according to the negative value.
But you can't draw with that negative brush size.

Reproducible: Always

Steps to Reproduce:
1. Map the airbush wheel to the brush size in the brush editor
2.
3.

Actual Results:  
Brush size is displayed the same as it's positive counterpart but. The result is that only half of the brush wheel is usable.

Expected Results:  
the lowest negative size in tangential pressure should be the smallest brush size in that case.

I'm not quite sure if the airbrush returns -1.0 and 1.0 or -255 and 255
Other devices could work with this since they return a range with 0 - 255
Comment 1 Marcus Kjeldsen 2016-04-10 11:12:32 UTC 
I can confirm on 3.0 Alpha 1, on win 10 with cintiq21ux
Comment 2 wolthera 2016-04-10 12:41:00 UTC 
Setting this to confirmed then.
Comment 3 eliotJ 2016-05-11 14:15:09 UTC 
Hi

This also exist in Krita v2.9.x or it's a regression in v3.0 ?
Comment 4 Pierre "bloodywing" Geier 2016-05-11 15:02:51 UTC 
The scroll wheel in Qt4 and 2.9.x had just the values 1, 0 and -1. Krita handled the axis for that correct but qt4 messed up reporting the correct values to krita.
Comment 5 eliotJ 2016-05-11 21:11:55 UTC 
Ok. Thank you Pierre for testing in 2.9.x.
Comment 6 Pierre "bloodywing" Geier 2016-08-27 14:51:08 UTC 
Update on this: The Brush wont get into a negative size now. But now only half of the wheel is used. So middle state of the wheel is like 0 size.
Comment 7 arturg 2016-10-04 22:27:52 UTC 
Created attachment 101423 [details]
the patch basically does the same as we did in krita 2.9
Comment 8 wolthera 2016-10-05 16:59:18 UTC 
artug, maybe put that patch on phabricator.kde.org instead?
Comment 9 arturg 2016-10-05 22:17:02 UTC 
done. https://phabricator.kde.org/D2950
do i need to add a reviewer myself, then who is able to test this?
Comment 10 Halla Rempt 2016-10-07 09:16:36 UTC 
Git commit 88f88fe7a432a0202db8dcba22f6b5f2e2d4868e by Boudewijn Rempt.
Committed on 07/10/2016 at 09:16.
Pushed by rempt into branch 'master'.

Differential Revision: https://phabricator.kde.org/D2950

M  +2    -1    libs/flake/KoPointerEvent.cpp

http://commits.kde.org/krita/88f88fe7a432a0202db8dcba22f6b5f2e2d4868e