Bug 335648

Summary:	Brush outline disappears when moved in non-OpenGL mode
Product:	[Applications] krita	Reporter:	Alicia Boya García (ntrrgc) <ntrrgc>
Component:	General	Assignee:	Krita Bugs <krita-bugs-null>
Status:	RESOLVED UNMAINTAINED
Severity:	normal	CC:	dimula73, halla
Priority:	NOR
Version First Reported In:	git master (please specify the git hash!)
Target Milestone:	---
Platform:	Compiled Sources
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	A patch disabling update events compression Screenshot

Description Alicia Boya García (ntrrgc) 2014-06-01 14:56:53 UTC

By default Krita shown the outline of the brush as your cursor, so you can see where you are going to paint.

Due to this bug when you move the cursor fast enough the outline is distorted or disappears for some time.

This makes moving the cursor uncomfortable, specially with small brush sizes. It does not happen in OpenGL mode.

Reproducible: Always

Steps to Reproduce:
1. Disable OpenGL mode (default)
2. Choose a small brush
3. Move the cursor
Actual Results:  
The cursor almost disappears while you are moving it.

Expected Results:  
The cursor should be visible every time during the movement.

Comment 1 Dmitry Kazakov 2014-06-06 05:06:52 UTC

Created attachment 87036 [details]
A patch disabling update events compression

Hi, Juan!

Could you please test whether the attached patch makes any difference for you?

PS:
Here is how to apply a patch, just in case...
https://answers.launchpad.net/krita-ru/+faq/2561

Comment 2 Alicia Boya García (ntrrgc) 2014-06-06 16:42:27 UTC

Sorry, but no, it does not seem to make a great difference.

Indeed this looks like it's not only a thing of the brush outline, but the entire canvas looks like it has been rendered without being fully updated. See the attached screenshot.

Comment 3 Alicia Boya García (ntrrgc) 2014-06-06 16:42:55 UTC

Created attachment 87040 [details]
Screenshot

Comment 4 Dmitry Kazakov 2014-06-06 17:25:17 UTC

Well, such partial updates are expected, especially in non-openGL mode, because the image is calculated gradually

Comment 5 Alicia Boya García (ntrrgc) 2014-06-06 17:34:31 UTC

Anyway, Qt shouldn't draw the changes until they're ready, right?
El 06/06/2014 19:25, "Dmitry Kazakov" <dimula73@gmail.com> escribió:

> https://bugs.kde.org/show_bug.cgi?id=335648
>
> Dmitry Kazakov <dimula73@gmail.com> changed:
>
>            What    |Removed                     |Added
>
> ----------------------------------------------------------------------------
>                  CC|                            |dimula73@gmail.com
>
> --- Comment #4 from Dmitry Kazakov <dimula73@gmail.com> ---
> Well, such partial updates are expected, especially in non-openGL mode,
> because
> the image is calculated gradually
>
> --
> You are receiving this mail because:
> You reported the bug.
>

Comment 6 Dmitry Kazakov 2015-06-25 13:26:33 UTC

Confirmed

Comment 7 Halla Rempt 2017-03-01 11:49:11 UTC

I'm sorry, but we're not going to try and fix issues like this in the qpainter canvas anymore: it's a fallback for those without working hardware/drivers at this point. Users experiencing this problem should enable one of the hardware cursors in the settings dialog.