Bug 373191 - Drawing has either "no pressure sensitivity+freezing brushes" or the brush is offset from the pen depending on the info in the "Choose Screen Resolution dialog" on multiscreen (cintiq)
Summary: Drawing has either "no pressure sensitivity+freezing brushes" or the brush is...
Status: RESOLVED WORKSFORME
Alias: None
Product: krita
Classification: Applications
Component: Tablets (tablet issues are only very rarely bugs in Krita!) (show other bugs)
Version: 3.1 Beta
Platform: Microsoft Windows Microsoft Windows
: NOR grave
Target Milestone: ---
Assignee: Krita Bugs
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2016-12-02 16:05 UTC by kirtai2000
Modified: 2017-07-14 23:22 UTC (History)
2 users (show)

See Also:
Latest Commit:
Version Fixed In:


Attachments
Screenshot of Kritas Screen Resolution dialog (13.75 KB, image/png)
2016-12-08 00:07 UTC, kirtai2000
Details
Screenshot of my monitor setup (83.89 KB, image/png)
2016-12-08 00:08 UTC, kirtai2000
Details
Log with automatic settings (330.71 KB, text/plain)
2016-12-08 00:08 UTC, kirtai2000
Details
Log with manual screen settings (114.29 KB, text/plain)
2016-12-08 00:08 UTC, kirtai2000
Details

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Description kirtai2000 2016-12-02 16:05:11 UTC
I have a three monitor setup as follows:
1920x1200 (monitor) 1920x1080 (monitor) 2560x1440 (Cintiq 27QHD)

In the "Choose Screen Resolution" dialog, the wintab and Qt autodetected sizes are 6400x1440, offset 0x0

If I accept this, the brush draws on an offset from the pen position.

If I change it to manual and input a size of 2560x1440, offset 0x0, the brush now tracks the pen perfectly. *However*, pressure sensitivity stops working and the brush freezes in place when I lift the pen while it's drawing.

I've seen these two bugs reported before but this seems to be a common cause and I can trigger either at will just by changing the screen resolution settings.

I have experimented with different screen resolution settings but they all produce either offset drawing or no pressure sensitivity with freezing.

This only happens in kritas canvas. MyPaint, Clip Studio Paint, Drawpile and others all work correctly.

I have marked this grave since it seems impossible to have both an accurate brush with pressure sensitivity which doesn't freeze on lifting the pen.
Comment 1 kirtai2000 2016-12-02 16:11:49 UTC
This is under Windows 10 64bit.
Comment 2 Halla Rempt 2016-12-07 12:40:55 UTC
How are monitors setup? In my setup, I've got two monitors and a cintiq as well, the two monitors are next to each other, the cintiq below the left monitor. In the wacom settings, I make sure that I selected the cintiq, and then everything works well. But that's with Windows 7. It might be easiest to attach a screenshot of the display setup dialog and the cintiq settings dialog.
 
Also, can you make a tablet log using the latest rc? 

https://docs.krita.org/KritaFAQ#What_if_your_tablet_is_not_recognized_by_Krita.3F

https://krita.org/en/item/krita-3-1-release-candidate/
Comment 3 kirtai2000 2016-12-08 00:07:39 UTC
Created attachment 102676 [details]
Screenshot of Kritas Screen Resolution dialog
Comment 4 kirtai2000 2016-12-08 00:08:03 UTC
Created attachment 102677 [details]
Screenshot of my monitor setup
Comment 5 kirtai2000 2016-12-08 00:08:35 UTC
Created attachment 102678 [details]
Log with automatic settings
Comment 6 kirtai2000 2016-12-08 00:08:56 UTC
Created attachment 102679 [details]
Log with manual screen settings
Comment 7 kirtai2000 2016-12-08 00:10:50 UTC
I've attached screenshots of the Monitor and screen resolution setups.

Screen 1 is the Cintiq
Screen 2 is a 1920x1080 monitor
Screen 3 is a 1920x1200 monitor (Primary display).

(No, I don't know why they're numbered right to left when they're set up as left to right.)


I've also attached the DebugView logs for both setups.

Wintab.log is when I use the display settings that Wintab suggests. (6400x1440)
Manual.log is when I use the manual settings of 2560x1440.



(sorry for any spam, this bug tracker isn't working quite as I expected regarding attachments)
Comment 8 Halla Rempt 2016-12-08 09:18:06 UTC
Well, the 3, 2, 1 order is probably the cause of the problem. I suspect that if you make the x offset 3840, it works...
Comment 9 kirtai2000 2016-12-09 12:19:56 UTC
Unfortunately setting the x offset to 3840 doesn't work.

The pressure sensitivity works and the brush freezing stop happening but instead the brush has a scaled offset.

With this offset, if I move the pen from the left edge of the tablet to the right edge, the brush moves from near the centre of the tablet to the right edge.

Note that these problems are only with the brush on the canvas. Moving the pen over Krita's GUI elements has perfect tracking regardless of the settings.

I also tested with and without OpenGL and got the same results.
Comment 10 Halla Rempt 2016-12-09 18:53:40 UTC
A tablet works like this: it first sends a tablet event. If the tablet event is not accepted, and most things like menus and toolbars don't send tablet events, it is sent again as a mouse event. Since that's much simpler and much more standard and less likely to be influenced by things like the difference between monitor resolution & tablet resolution, much less can go wrong.
Comment 11 kirtai2000 2016-12-09 20:57:50 UTC
OK, this turned out to be a case of rogue preference files that were not removed by uninstalling the driver.

I had to use the "Wacom Tablet Preference File Utility" to purge all of the preference files. After I did this, Krita's autodetection facility worked perfectly. For the record, I used the wintab setting.

Apparently it's a known problem that also affects Paint Tool SAI.
Some more information in the second answer here 
https://www.systemax.jp/en/sai/faq_tablet.html
Comment 12 kirtai2000 2016-12-09 21:57:34 UTC
Proposed addition to the FAQ entry "How to fix a tablet offset on multiple screen setup on Windows"

If you have a Wacom tablet, an offset in the canvas can be caused by a faulty Wacom preference file which is not removed or replaced by reinstalling the drivers.

To fix it, use the "Wacom Tablet Preference File Utility" to clear all the preferences. This should allow Krita to detect the correct settings automatically.
(WARNING, this will reset your tablets configuration so you will need to recalibrate/reconfigure it).