Bug 400097

Summary:	Cursor flickering on switching between cursor types
Product:	[I don't know] kde	Reporter:	b8h8vm0lf
Component:	general	Assignee:	Unassigned bugs mailing-list <unassigned-bugs>
Status:	RESOLVED DOWNSTREAM
Severity:	minor	CC:	b8h8vm0lf
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	Neon
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description b8h8vm0lf 2018-10-21 08:45:57 UTC

For example, I'm moving cursor arrow on text. Before it turns to "I" for text selecting I clearly see the intermediate cursor texture (can't see what type is it) located right or left from current cursor position. Same when I moving cursor arrow to the border of screen to resize. It looks like glitch or flickering.

Bug presents with all modern cursor themes (Breeze, Adwaita) and not present in KDE Classic. It's lasting for about 2 years on different distributions.

KDE Neon, Plasma ver. 5.14.1 - still present.

Comment 1 b8h8vm0lf 2018-10-21 08:46:23 UTC

Found forum message about this:

https://forum.kde.org/viewtopic.php?f=67&t=133362

Comment 2 b8h8vm0lf 2018-10-27 11:25:26 UTC

https://drive.google.com/file/d/1bV7okri0I95tkCOqo-6Z-axnN3-BXk9U/view?usp=sharing

Above is link to a slo-mo video. You can clearly see what's happening when I'm moving cursor straight down from text:
1. "I" cursor
2. Arrow cursor appears 5 px left from "I" cursor
3. Arrow cursor leaps to the 15 px right-down diagonal

On the monitor it looks like flickering jumping of cursor.

Comment 3 Christoph Feck 2018-11-09 12:35:44 UTC

Which video drivers? Do you see the same issue on systems with different video hardware?

Comment 4 b8h8vm0lf 2018-11-11 01:50:18 UTC

amdgpu 18.0.1
libdrm-amdgpu1 2.4.91
linux 4.19.0

On Radeon RX 570.

I haven't another hardware, but people say they haven't same issue on other hw and also firstly asked me about video driver.

Comment 5 Christoph Feck 2018-11-21 21:31:48 UTC

The issue is very likely in the video drivers, possibly not correctly syncronizing cursor position and cursor shape updates. I suggest to report it to the developers of your video drivers (your distribution might help to locate these).

Comment 6 b8h8vm0lf 2018-11-22 13:42:40 UTC

So, I have some experiments with video driver settings and I have no issues with such options 20-amgpu.conf:

Option "SWcursor" "true"
Option "TearFree" "true"

I will create a bug to amdgpu devs. Thank you.