Bug 394187

Summary: Different color is shown on canvas when creating image with RGB float16/float32.
Product: [Applications] krita Reporter: a246246_246-kde
Component: Color modelsAssignee: Krita Bugs <krita-bugs-null>
Status: RESOLVED FIXED    
Severity: normal CC: halla
Priority: NOR    
Version First Reported In: 4.0.3   
Target Milestone: ---   
Platform: macOS (DMG)   
OS: macOS   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: screenshot for wrong color

Description a246246_246-kde 2018-05-13 05:15:10 UTC
Created attachment 112609 [details]
screenshot for wrong color

In macOS High Sierra 10.13.4, create new document selecting RGB/Alpha Model, 16-bit float or 32-bit float depth, with default profile, and draw something using brush. When I select some pale bluish color, for example, R=0.05 G=0.74 B=1.00, yellowish line is drawn: whereas if I choose yellowish one, R=0.86 G=1.00 B=0.05, bluish lines are drawn.

When I save that canvas to tiff and show in Preview, color is correct.
But when I open that tiff with Krita, color becomes wrong again.
Comment 1 a246246_246-kde 2018-05-14 00:39:25 UTC
It looks this does not happened on Windows 7 (x64).

To reproduce this on Mac, create new document from menu and select Model RGB/Alpha and Depth to 16/32-bit float.  If you create other RGB model in creating document and change it later to float in specific color selector tab by checking 'Show Colorspace Selector' checkbox and select Depth to float values, painted color is the same as selected one.
Comment 2 Halla Rempt 2018-05-15 09:28:55 UTC
I suspect your mac has an AMD gpu?
Comment 3 a246246_246-kde 2018-05-15 14:02:47 UTC
Yes, my macBook Pro (Retina, 15-inch, Mid 2015) have 2 video cards:

Video Card              Type  Bus
AMD Radeon R9 M370X     GPU   PCIe
Intel Iris Pro          GPU   Built-In

But I show the krita window to Built-In Display: Intel Iris Pro 1536 MB
Comment 4 a246246_246-kde 2018-05-16 22:07:07 UTC
I knew nothing about this issue but with the help of gfxCardStatus tool I can observe graphic automatically switches to AMD when I invoke krita.
https://gfx.io/switching.html
Comment 5 Halla Rempt 2018-05-17 14:23:57 UTC
Iv'e seen this now as well.
Comment 6 Halla Rempt 2018-05-18 13:28:12 UTC
Fixed in https://phabricator.kde.org/R37:893e22d135ea