I confirm that I can also see this issue.
I did some digging to find the root cause and I couldn't find any traces of what is going wrong. So I checked the source code of my inspiring built-in effect: Invert
Interestingly, the blurriness can also be observed on the "Invert" effect which is built by KWin devs.
So I conclude that this is a bug on the KWin side when a window is using a shader.
Did some testing and the blurriness is only there on fractional scaling, if i use integer scaling it doesn't happen. The effect is working beautifully apart from that. I'm using 100% scaling for now until the root cause get fixed on kwin. For now, i think is ok to close this issue :) (thanks for the awesome work you're doing, i hope this effect is used on plasma 6)
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Originally posted by: matinlotfali
I confirm that I can also see this issue.
I did some digging to find the root cause and I couldn't find any traces of what is going wrong. So I checked the source code of my inspiring built-in effect: Invert
Interestingly, the blurriness can also be observed on the "Invert" effect which is built by KWin devs.
So I conclude that this is a bug on the KWin side when a window is using a shader.
More digging, here are some of the reported items that I believe are related:
https://bugs.kde.org/show_bug.cgi?id=480021
https://bugs.kde.org/show_bug.cgi?id=456965
Originally posted by: debnath-d
I was so excited to try out this effect! Works really great apart from this issue, which makes it unusable :(
Originally posted by: AndGuz
Maybe the issue will be fixed with plasma 6
Originally posted by: matinlotfali
I opened this issue on the official KWin repo:
https://invent.kde.org/plasma/kwin/-/issues/201
Ticket changed by: AndGuz
Originally posted by: AndGuz
Did some testing and the blurriness is only there on fractional scaling, if i use integer scaling it doesn't happen. The effect is working beautifully apart from that. I'm using 100% scaling for now until the root cause get fixed on kwin. For now, i think is ok to close this issue :) (thanks for the awesome work you're doing, i hope this effect is used on plasma 6)
Originally posted by: CeruleanDerpo
From what I understand maybe there is a fix?
https://bugs.kde.org/show_bug.cgi?id=461283#c9
Originally posted by: mufeedali
I think this should probably be reopened since the issue isn't present on the official effects anymore.
Ticket changed by: matinlotfali
Originally posted by: matinlotfali
Sadly the issue still stands and it is still present on effects that use shaders (i.e the official invert effect)
Originally posted by: mufeedali
Sorry for the misreport, looks like the issue is still present in the Invert effect