Rawtherapee: Toolbar scroll bug workaround

[TooWaBoo]

Played with the new scrolled toobars and found a possible workaround for the freeze.
First of all the toolbar freezes only if you scroll in the bottom part of the toolbar. (It looks like Gtk bug).
What I did is to add a huge margin to the bottom of the toolbar container and cut it off with the scrolled tool container, e.g.

#EditorTopPanel {
    margin-bottom: 50px;
}
#EditorToolbarTop {
    margin-bottom: -50px;
}

With this workaround the toolbar doesn't freeze anymore. I've modified the TooWaBoo theme and fixed the top and bottom toolbar. There is still a problem with the bottom toolbar. It's not possible to scroll over the comboboxes.
To fix the Query- and Filter toolbar I need another container inside the scroll containers.

Please test these modifications if it works on other OS too.
TooWaBlue_Scroll_test-GTK3-20_.css.txt

I've tested on Win10 x64 and Gtk+3.24.0

ping @Hombre57 , @Beep6581

[Benitoite]

No problems with repo TWB themes or Scroll_test on macOS (gtk 3.22.30) here.

[Hombre57]

@TooWaBoo What's your GTK and OS version ?

[TooWaBoo]

@Hombre57
Win10 x64 and Gtk+3.24.0

[Hombre57]

@TooWaBoo That's weird ! 3.22 here and it works better than in 3.24 !? I'm still trying to create a better workaround, usable for Gtk3.18 users too.

[Benitoite]

Upgraded to gtk+3.24.0 on macOS and have flickering tooltip titles also. Had one non-repeatable crash scrolling a toolbar while on TWB-dark. Scroll_test still has flickering tooltip titles.

[Hombre57]

@TooWaBoo Does the new scrolled-toolbar-fix branch fix the freeze problem (w/o your patch) ?

[TooWaBoo]

@Benitoite
I've found these issues in RT with Gtk+3.24.0
_Filename tooltip over thumbnails and History tooltip are flickering.
Scrolling with the mouse wheel in the file browser and filmstrip doesn't work anymore.
Zooming with the mouse wheel in the preview doesn't work anymore.
Rounding of "em" values in themes has changed. (this affects only the TWB theme)_

@Hombre57
I will test.

[TooWaBoo]

@Hombre57
The answer is here: https://github.com/Beep6581/RawTherapee/issues/4035#issuecomment-419275367

[Hombre57]

@TooWaBoo Damn it!

I tried again to reproduce the error with dev minus the unsupported line, but now it works ! So I don't understand why it froze before and how to reproduce.

Could you start RT from a com and line console, but executing this first : set GTK_DEBUG=interactive. Then use the top left icon of the inspector window to locate the toolbar's widget. It should have the same height than its children. I know that containers can be smaller than the child in HTML, but don't know for GTK.

[TooWaBoo]

@Hombre57
There is no inspector. I'm on Windows and have only MSYS installed.

[heckflosse]

@TooWaBoo in msys2 comandline execute this (no set)

GTK_DEBUG=interactive rawtherapee

[TooWaBoo]

@heckflosse
Thanks, it works
@Hombre57
Bingo, I've found the culprit, like my first thought there is a hidden scrollbar which makes this trouble.
In css it can be fixed with this simple style.

.scrollableToolbar scrollbar:not(.overlay-indicator) slider:not(.dummy) {
    padding: 0;
    margin: 0;
    min-height: 0;
    min-width: 0;
    border: none;
}

[Beep6581]

Using CSS to hack around UI issues should be done as a last resort.

1. What exactly is the problem? Scrolling doesn't work when using GTK+ 3.24 when hovering over the area into which a horizontal scrollbar would appear, is that correct?
2. Is it really a bug, or are we doing something wrong?
3. Can it be fixed in RT's GTK+ code?
4. Have you reported it upstream to GTK+? If so, please provide a link.

@Hombre57
https://developer.gnome.org/gtk3/stable/ch26s02.html#id-1.6.3.4.14

[TooWaBoo]

1. Yes but it's not related to the Gtk version
2. That's what we try to figure out
3. I don't know
4. I'm the wrong person to do that. I didn't write the code and I don't understand the code in details

[TooWaBoo]

Only for testing.
RawTherapeeScrollfix-GTK3-20_.css.txt
TooWaBlueScrollfix-GTK3-20_.css.txt

[Benitoite]

@Benitoite
I've found these issues in RT with Gtk+3.24.0
Filename tooltip over thumbnails and History tooltip are flickering.

This flickering appears to be a commonality between windows and mac.

Testing Scrollfix on macOS, seems to scroll fine.

Occasionally do get a crash involving the quartz backend: https://gitlab.gnome.org/GNOME/gtk/issues/1312

[TooWaBoo]

@Benitoite
Thanks for the feedback.
btw. Can you check if these issues https://github.com/Beep6581/RawTherapee/issues/4784 exists on MacOS too and leave a comment there, please?

[Hombre57]

@TooWaBoo @Beep6581 @Benitoite

Ok to merge scrolled-toolbar-fix into dev ?

[TooWaBoo]

Yes, it fixes some GTK+ 3.24 issues too, but the toolbutton scrollbug in GTK+ 3.24 still exists.
https://github.com/Beep6581/RawTherapee/issues/4784

[TooWaBoo]

The toolbar-scroll-bug still exists in GTK+ >3.18. ShalI I activate the theme workaround?

[Hombre57]

@TooWaBoo I don't manage to find a better way using Gtk's function, so I'd say yes.

[Hombre57]

And could you add it in RawTherapee's theme as well ?

[TooWaBoo]

OK, I will do it this evening.

[TooWaBoo]

Done, closing issue.