Bug 457442

Summary:	Invert effect no longer applies to WindowHeap-based effects
Product:	[Plasma] kwin	Reporter:	andy <andy>
Component:	effects-window-management	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	CONFIRMED ---
Severity:	normal	CC:	andriy.parhomenko, nate
Priority:	NOR	Keywords:	accessibility, regression
Version First Reported In:	5.25.3
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description andy 2022-08-03 09:08:11 UTC

SUMMARY
If using the invert effect or a custom kwin effect, before recent changes the invert effect would apply to the whole desktop, including when overview and present windows were shown.

Now, overview and present windows seem to render over everything, making any whole-desktop effect like invert not have an effect.

similar to https://bugs.kde.org/show_bug.cgi?id=455895 but different.

STEPS TO REPRODUCE
1. Enable Invert effect (Meta+Ctrl+I)
2. Toggle Present windows - observe
3. Toggle Overview - observe

OBSERVED RESULT
Screen is no longer inverted when present windows is shown.
Screen is no longer inverted when overview is shown.

EXPECTED RESULT
Screen is inverted when present windows is shown.
Screen is inverted when overview is shown.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Arch Linux 5.15.55-2-lts
KDE Plasma Version:  5.25.3
KDE Frameworks Version:  5.96.0
Qt Version: 5.15.5

ADDITIONAL INFORMATION

Comment 1 Nate Graham 2022-08-04 19:11:33 UTC

Can reproduce.

Comment 2 Vlad Zahorodnii 2022-09-16 09:30:14 UTC

WindowHeap-based effects are rendered differently, while the invert effect operates per window basis. Would need to think about it. There are couple of challenges - the invert effect provides too many features that make it hard to make it work consistently in normal desktop mode and in effects such as overview

Comment 3 ratijas 2022-09-16 09:58:21 UTC

Is the inversion formula itself invertible? I.e. can it be applied twice to get the original color? If so, then it shouldn't be too difficult to implement, sacrificing a bit of CPU/GPU in rare cases when a fullscreen inversion is combined with per-window ones.

Comment 4 andriy.parhomenko 2024-01-17 18:17:58 UTC

This is still present in Plasma 6 RC1.