Bug 472479

Summary: Gradient map filter failed to work on high bit depth
Product: [Applications] krita Reporter: Kampidh <qampidh>
Component: Filter LayersAssignee: Deif Lou <ginoba>
Status: RESOLVED FIXED    
Severity: normal CC: ginoba
Priority: NOR    
Version First Reported In: git master (please specify the git hash!)   
Target Milestone: ---   
Platform: Microsoft Windows   
OS: Microsoft Windows   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Video describing the bug

Description Kampidh 2023-07-21 20:33:25 UTC
Created attachment 160435 [details]
Video describing the bug

git master 887a540d0b571c4b0cf9d0618e6469375f3b5e15

SUMMARY
Gradient map filter layer didn't seem to work on high bit depth image with current master (887a540).

STEPS TO REPRODUCE
1.  Create a high bit depth canvas (>8 bpc)
2.  Paint with some grayscale / BW gradient
3.  Use gradient map filter layer

OBSERVED RESULT
Gradient map didn't applied properly and looks flat. And when the 2nd point gets dragged quite closer to the first one, the colors are broken.

EXPECTED RESULT
The colors are mapped properly

SOFTWARE/OS VERSIONS
Windows: 10 64bit

ADDITIONAL INFORMATION
Digging deeper, I tried to revert commit 6af8af9 (Remove the profile parameter from to/from QColor) and the gradient map seems to work normally again.
Comment 1 Deif Lou 2023-07-21 21:41:21 UTC
Probably introduced by commit 6af8af90342d498547d1ae123d046223545f4588