Blur producing black artifacts/shadowlines

[domsch1988]

Platform: Antergos, i3-gaps

GPU, drivers, and screen setup: Intel 4th gen integrated graphics, two displays, xrandr

Compton version: v0.1_beta2.5

Compton configuration: see image below. All Blur-Kernels except "7x7box" are currently commented. They where for troubleshooting. Also, some of the used options are not needed, again, where used for troubleshooting. The effect was visible from the start, with nothing configured except blur-background.

Steps of reproduction

Using Terminator, set 0.85 background transparency in the Profile. Enable Bluring in Compton (more/higher blur-kernels intensify the effect)

Expected behavior

Clean Blur without rendering artifacts

Current Behavior & Other details

Noticeable in Terminal: When moving the cursor arround, black lines are rendered on the background. See image below. They disappear when the window looses focus.

[ghost]

I also experience this behavior, but only when I set a swap method and only in firefox. Could be something else on my system, but I think it could be related.

[ghost]

Actually it happens in seemingly random places around window edges as well, it's just most noticable in firefox...

[ghost]

Interestingly, it also does this if shadows are disabled. I notice this on my Nvidia GPU, but not on my laptop with integrated graphics like yours...

[ghost]

Can you try setting glx-swap-method to 0 and seeing if the issue persists?

[serin113]

This behavior also appears for me in all terminals I've used (Guake, xfce4-terminal, rxvt-unicode).

Weirdly, these shadow-line artifacts disappear immediately once the affected terminal window goes out of focus.

Can you try setting glx-swap-method to 0 and seeing if the issue persists?

@Chili-Bebber The issue seems to disappear when swap method is set to undefined/0. Actually, the issue only appears when the swap method is set to buffer-age (-1).

[siyia2]

i can confirm that, i can also use glx-swap-method to1 which is the fastest and the lines go away.

[distek]

Wanted to add a note for this. Setting glx-copy-from-front to disabled corrected it for me. This is with glx-swap-method at any level.

For reference, here's the relevant part of my config:

backend = "glx";
glx-swap-method = 0;
mark-wmwin-focused = true;
mark-ovredir-focused = true;
detect-client-opacity = false;
unredir-if-possible = false;
refresh-rate = 0;
vsync = true;
detect-transient = true;
detect-client-leader = true;
glx-copy-from-front = false;
xrender-sync-fence = false;

Using: Manjaro i3 Community Edition (5.3.11-1-MANJARO) LXTerminal (with a native transparent background color) Nvidia GT 750M (Only VGA adapter on machine)