| Summary: | Mouse wheel does not work properly in viewer | ||
|---|---|---|---|
| Product: | [Applications] kphotoalbum | Reporter: | Andreas Schleth <schleth_es> |
| Component: | Viewer | Assignee: | KPhotoAlbum Bugs <kphotoalbum-bugs-null> |
| Status: | RESOLVED FIXED | ||
| Severity: | normal | CC: | johannes, tl |
| Priority: | NOR | ||
| Version First Reported In: | GIT master | ||
| Target Milestone: | --- | ||
| Platform: | openSUSE | ||
| OS: | Linux | ||
| Latest Commit: | https://invent.kde.org/graphics/kphotoalbum/commit/12bd7cc6f9af57a4a85d0eab86e734657938377e | Version Fixed/Implemented In: | |
| Sentry Crash Report: | |||
I can't reproduce this so far. My best guess is that this was introduced by commit 5505780551caee4e0a93d8ae1a7e7bf9fe7cf7c4. Do you, by any chance, have a mouse wheel that can scroll sideways? I tried this with both my real mouse and my Trackman (trackball with mouse wheel emulation). Both work as expected … Oh my, this is one of those ... My mouse is just a regular Logitech 2 buttons and a wheel acting as middle button. As I had a dead rodent recently, I even tried another mouse to the same effect (some Chinese brand), same effect. Same on a different machine (same system, but older cpu) and with a right-handed mouse. But I will check with my laptop which runs Ubuntu... ... well it runs 20.04 ... which is too old for the current build system (again!). So I will report back when I have updated that machine to something newer (hoping that the update will not break all the Tuxedo drivers). Is there newer info which packages to install to build with Ubuntu? The data in https://community.kde.org/KPhotoAlbum/build_instructions are a bit dated and do not work for me. OK giyf... I found the missing package, updated the install instructions :-) and built the thing on Ubuntu 22.04 and ... ... it works as expected (by the devs, not by me :-). The mouse wheel works forwards and backwards. Thus, this is a bug not to be found with Ubuntu 22.04 but on openSuse Leap 15.4. My Ubuntu has KDE 5.92.0 Qt 5.15.3 and KPA is at 5.9.1-104-... Kernel is 5.15.0 My Suse is at KDE 5.90.0 Qt 5.15.2 Kernel 5.14.12 - so just a tiny bit behind on everything. Perhaps I need to find the commit that changed the behaviour... so I am going to brush up my git know-how. So, I did some git bisect starting with a good version from April 2022 and the bug first appears in: 5505780551caee4e0a93d8ae1a7e7bf9fe7cf7c4 is the first bad commit commit 5505780551caee4e0a93d8ae1a7e7bf9fe7cf7c4 Author: Johannes Zarl-Zierl <johannes@zarl-zierl.at> Date: Mon Oct 3 23:46:01 2022 +0200 WIP: Port away from deprecated Qt APIs. This commit is marked work in progress because I have disabled two deprecation warnings for QMap::insertMulti so that I can enable QT_DISABLE_DEPRECATED_BEFORE for Qt 5.15. Does this help? Hi Andreas, Am Sonntag, 11. Dezember 2022, 20:23:26 CET schrieben Sie: > So, I did some git bisect starting with a good version from April 2022 and > the bug first appears in: > > 5505780551caee4e0a93d8ae1a7e7bf9fe7cf7c4 is the first bad commit Ok, so my hunch was correct. > Does this help? I'm not sure. The porting instructions from the old to the new API are a bit sparse on the details. My working assumption to the bug is that on this particular system your mouse wheel for some reason is emitting a horizontal scroll instead of a vertical scroll (the old API did not differentiate between the two). For the viewerwidget it makes sense to allow horizontal scrolling anyways, so I'll just add that. Please keep an eye out for similar problems with any other widgets in KPhtotoAlbum on your OpenSuse systems... Cheers, Johannes P.S.: Btw. thanks for updating the wiki page! You really know how to make a dev's day better ;-) Git commit a833229b0c04516067bc6e490fbca4d7c370f0c7 by Johannes Zarl-Zierl. Committed on 11/12/2022 at 21:52. Pushed by johanneszarl into branch 'master'. Allow horizontal scrolling in ViewerWidget M +1 -1 Viewer/ViewerWidget.cpp https://invent.kde.org/graphics/kphotoalbum/commit/a833229b0c04516067bc6e490fbca4d7c370f0c7 Git commit d908ac10be06b629ad63902971994f876dbc86cf by Johannes Zarl-Zierl. Committed on 11/12/2022 at 22:06. Pushed by johanneszarl into branch 'master'. Properly allow horizontal scrolling in ViewerWidget Improving upon a833229b, I took a look at the implementation of the deprecated method QWheelEvent::delta() and used the same logic to determine scroll orientation. M +3 -1 Viewer/ViewerWidget.cpp https://invent.kde.org/graphics/kphotoalbum/commit/d908ac10be06b629ad63902971994f876dbc86cf Hi Johannes,
unfortunately the bug is still there in v5.9.1-106-gd908ac10 ...
But at least we know where to look for it.
So I added some diagnostic print:
std::cout << "check deltax" << pxDelta.x() << " deltay" << pxDelta.y() << "\n";
Which recorded on one forward and backward increment:
check deltax0 deltay0
check deltax0 deltay0
The effect on screen was the older next picture for each event.
Then I did some digging in the docs and found in https://doc.qt.io/qt-5/qwheelevent.html :
"There are two ways to read the wheel event delta: angleDelta() returns the deltas in wheel degrees. These values are always provided. pixelDelta() returns the deltas in screen pixels, and is available on platforms that have high-resolution trackpads, such as macOS."
Improving my test output to:
const auto anDelta = event->angleDelta();
std::cout << "check deltax " << pxDelta.x() << " deltay " << pxDelta.y() << "\n";
std::cout << "check anglex " << anDelta.x() << " angley " << anDelta.y() << "\n";
produced:
check deltax 0 deltay 0
check anglex 0 angley 120
check deltax 0 deltay 0
check anglex 0 angley -120
So, my suggestion would be to use the angleDelta instead of the pixelDelta like this:
...
const auto anDelta = event->angleDelta();
const bool isHorizontal = (qAbs(anDelta.x()) > qAbs(anDelta.y()));
if ((!isHorizontal && anDelta.y() < 0) || (isHorizontal && anDelta.x() < 0)) {
...
I did the same test output on the Ubuntu machine: there the pixelDelta showed "120" / "-120" - the same as angleDelta on my openSuse.
So we might assume, that the Qt-guys did change something in between the last minor releases.
The suggested fix works on both my platforms :-)
Thanks for the analysis! The suggested fix does not break anything on my end either... Git commit 12bd7cc6f9af57a4a85d0eab86e734657938377e by Johannes Zarl-Zierl. Committed on 11/12/2022 at 23:36. Pushed by johanneszarl into branch 'master'. Always use angle instead of pixel scrolling for wheel events On OpenSuse apparently sometimes QWheelEvent::pixelDelta() is zero, but QWheelEvent::angleDelta() is not. M +3 -3 DateBar/DateBarWidget.cpp M +3 -3 Viewer/ViewerWidget.cpp https://invent.kde.org/graphics/kphotoalbum/commit/12bd7cc6f9af57a4a85d0eab86e734657938377e How nice! v5.9.1-109-g12bd7cc6 works for me (TM) |
SUMMARY Mouse wheel only goes backwards in time when viewing images in the viewer. STEPS TO REPRODUCE 1. find a selection of a few images in the thumbnail browser ("kphotoalbum --demo" works fine) 2. double click on one in the middle of the selection to start the viewer 3. try the pg-up/pg-down arrow keys: they work as intended. 4. now, try the mouse wheel: turning forwards and backwards a few clicks OBSERVED RESULT 5. each turn increment will switch to an older image regardless of direction 6. after you turned long enough you will get stuck on the first image of the series (with the demo this is "new wave") and the mouse wheel will not change anything anymore. (pg-down still works) EXPECTED RESULT Mouse wheel forwards should work as pg-up, wheel backwards should work as pg-down. This bug was introduced somewhere in 5.9 development. In 5.8.1 the function is still OK. SOFTWARE/OS VERSIONS Linux/KDE Plasma: OpenSuse Leap 15.4 KPA: v5.9.1-103-g00d997eb (also in: v5.9.1-102-ga2fa6493) KDE Frameworks Version 5.90.0 Qt Version 5.15.2 (built against 5.15.2)