Bug 412011

Summary: Changing cursor color to black in settings makes the brush outline to disappear
Product: [Applications] krita Reporter: Raghavendra kamath <raghu>
Component: UsabilityAssignee: Krita Bugs <krita-bugs-null>
Status: CONFIRMED ---    
Severity: normal CC: ahab.greybeard, tamtamy.tymona, tgdev001
Priority: NOR    
Version First Reported In: git master (please specify the git hash!)   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Raghavendra kamath 2019-09-18 06:52:01 UTC 
SUMMARY
If the user chooses a black color as cursor color in the setting, the brush outline shape is not shown on canvas.

STEPS TO REPRODUCE
1. Open a new document in krita and check the brush outline on canvas
2. Go to settings > configure Krita > General > cursor
3. change the cursor color to black
4. Now check the brush outline on canvas

OBSERVED RESULT
No outline is shown as if it is transparent

EXPECTED RESULT
Bursh outline should be shown

Operating System: Arch Linux 
KDE Plasma Version: 5.16.5
KDE Frameworks Version: 5.62.0
Qt Version: 5.13.1
Kernel Version: 5.2.14-arch2-1-ARCH
OS Type: 64-bit
Processors: 8 × Intel® Core™ i7-4790K CPU @ 4.00GHz
Memory: 15.6 GiB of RAM
Comment 1 Ahab Greybeard 2019-09-18 15:39:50 UTC 
The Cursor Colour setting does not in fact change the cursor colour, it changes the brush outline colour.

The brush outline colour seems to be formed from an arithmetic/logical combination of the image background colour and the 'cursor colour' with the intention of making them different.

Using a particular shade of red for cursor colour and with a particular shade of green on the image, the brush outline becomes invisible, as I just accidentally discovered. I suspect that this is because it has become the same colour as the background green pixels.

It may be that every colour choice shows this effect with the right combinations.

Black seems to give no change for every image pixel colour. This may be inevitable for some colour no matter what technique is used.
Comment 2 Ahab Greybeard 2019-09-18 15:41:10 UTC 
Setting to Confirmed because the report does describe the behaviour noted.
Comment 3 Tiar 2021-03-27 20:10:10 UTC 
I think this might be closed as INTENTIONAL... or changed to wish. Ahab's explanation on why this happens is correct. I guess a simple fix would be to use a grey outline instead.
Comment 4 stephen 2024-03-05 18:10:29 UTC 
(In reply to Tiar from comment #3)
> I think this might be closed as INTENTIONAL... or changed to wish. Ahab's
> explanation on why this happens is correct. I guess a simple fix would be to
> use a grey outline instead.

Not gray outline. But pure white/black outline depending on the color it hovers on. 
Can be added as a new color mode for the cursor.