Bug 452739

Summary:	Outline drag previews for the rectangle and ellipse tools constantly stutter around from their actual effective position, especially at high zoom levels
Product:	[Applications] krita	Reporter:	tomtomtomreportingin
Component:	Tools	Assignee:	Dmitry Kazakov <dimula73>
Status:	RESOLVED FIXED
Severity:	normal	CC:	1012468643, dimula73
Priority:	NOR	Keywords:	regression
Version First Reported In:	5.0.5
Target Milestone:	---
Platform:	Appimage
OS:	Linux
Latest Commit:	https://invent.kde.org/graphics/krita/commit/35e3e31afc3e0f879103a43ff8c6c57caa9c3fa8	Version Fixed In:
Sentry Crash Report:

Description tomtomtomreportingin 2022-04-18 16:26:33 UTC

SUMMARY
In Krita 5, the outline drag previews for rectangle/ellipse tools and their corresponding selection tools will constantly stutter around into misleading positions as the user drags from one point to another, often resulting in imprecise results.

STEPS TO REPRODUCE
1. Zoom in 800% for easier observance.
2. Select the Elliptical selection tool.
3. Drag on canvas, observe ellipse as you drag, observe result.

OBSERVED RESULT
The preview constantly jumps and the final result often doesn't match.

EXPECTED RESULT
The preview should be fully accurate with a matching result.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Debian sid
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.90.0
Qt Version: 5.12.12 (appimage)

Comment 1 tomtomtomreportingin 2022-04-18 16:27:44 UTC

Since this issue starts occurring as of Krita 5.0, marking this is a regression.

Comment 2 Lynx3d 2022-04-28 14:55:45 UTC

*** Bug 453130 has been marked as a duplicate of this bug. ***

Comment 3 tomtomtomreportingin 2022-04-30 17:11:09 UTC

The duplicate report was previously set to confirmed, so setting this report to confirmed.

Comment 4 Dmitry Kazakov 2022-06-17 14:43:37 UTC

The problem in the implementation of m_moveCenter functionality, which doesn't work well with rounding of the corners

Comment 5 Dmitry Kazakov 2022-06-17 14:49:55 UTC

Git commit 4f0137a120cb6cfdfaba19a3ea7d12537a1c32a4 by Dmitry Kazakov.
Committed on 17/06/2022 at 14:49.
Pushed by dkazakov into branch 'master'.

Fix dizzy outline in rectangle and ellipse tools

We don't have to apply `m_dragCenter` offset after adjusting
the rectangle endpoints.

M  +1    -7    libs/ui/tool/kis_tool_rectangle_base.cpp

https://invent.kde.org/graphics/krita/commit/4f0137a120cb6cfdfaba19a3ea7d12537a1c32a4

Comment 6 Dmitry Kazakov 2022-06-17 14:50:17 UTC

Git commit 82766ef025ded4b3345a67eed57bf0370980530f by Dmitry Kazakov.
Committed on 17/06/2022 at 14:50.
Pushed by dkazakov into branch 'krita/5.1'.

Fix dizzy outline in rectangle and ellipse tools

We don't have to apply `m_dragCenter` offset after adjusting
the rectangle endpoints.

M  +1    -7    libs/ui/tool/kis_tool_rectangle_base.cpp

https://invent.kde.org/graphics/krita/commit/82766ef025ded4b3345a67eed57bf0370980530f

Comment 7 Xu Che 2022-06-21 12:12:31 UTC

Git commit 35e3e31afc3e0f879103a43ff8c6c57caa9c3fa8 by Xu Che, on behalf of Dmitry Kazakov.
Committed on 21/06/2022 at 08:02.
Pushed by shidao into branch 'xuche/T15555-pixel-perfect-ellipse-gsoc-2022'.

Fix dizzy outline in rectangle and ellipse tools

We don't have to apply `m_dragCenter` offset after adjusting
the rectangle endpoints.

M  +1    -7    libs/ui/tool/kis_tool_rectangle_base.cpp

https://invent.kde.org/graphics/krita/commit/35e3e31afc3e0f879103a43ff8c6c57caa9c3fa8