Bug report - scrollbar behavior when using laptop trackpad two finger scroll down is weird

Official support for: mutools.com
KVRer
4 posts since 3 May, 2019

Post Sat Apr 17, 2021 2:23 pm

As the topic title says, when I use my laptop trackpad to try and scroll down with two fingers in Mulab (for example, when I am trying to scroll through a list of modules), Mulab responds with movements on the scroll bar that do not correspond to what I am trying to do with the trackpad.

If I scroll down softly, Mulab scrolls upwards. If I scroll down hard, Mulab initially scrolls down, but then starts scrolling back up.

This only happens if I am trying to scroll down, when I scroll up, Mulab responds properly.

Info:

Mulab 8.7.6
Windows 10 Home
ASUS X541UV Laptop

KVRer
13 posts since 13 Nov, 2017

Post Sun Apr 18, 2021 3:25 am

+1 I've had the same issue on a Surface Pro 4.

User avatar
KVRian
1288 posts since 4 Oct, 2012 from Utah

Post Sun Apr 18, 2021 7:42 pm

Trackpads that use non-linear scroll events have issues with Mulab. Macbooks, Dell XPS, and many other "inertia" scroll drivers exhibit this issue.

User avatar
KVRAF
10972 posts since 24 Jun, 2008 from Europe

Post Sun Apr 18, 2021 8:41 pm

What are non-linear scroll events? Do you have more info / links on this?

User avatar
KVRian
1288 posts since 4 Oct, 2012 from Utah

Post Sun Apr 18, 2021 11:22 pm

https://en.wikipedia.org/wiki/Scrolling#UI_paradigms

Many applications these days are built for both kinetic and inertial scrolling. Here's a video I made explaining how these are non-linear at times:

https://www.youtube.com/watch?v=FGz9zCimk3w

I hope this makes sense.

Edit:

The rough idea is that faster swipes = faster scrolls when using inertial scrolling, but agnostic when using kinetic scrolling. Think of it like scrolling on a smartphone. Flicking the screen does inertial scrolling with speed depending on how fast you flick the screen (non linear), but dragging is a linear change (like a scroll wheel) as you're simply "panning" the screen.

Edit No. 2:

https://stackoverflow.com/questions/297 ... in-java-fx

This goes over the idea of setting a zoom/scale factor

User avatar
KVRAF
10972 posts since 24 Jun, 2008 from Europe

Post Mon Apr 19, 2021 2:26 am

Thx for the info Dakkra.

Note that MuLab does not yet support gestures, and thus such 2 finger actions are unsupported.
I also don't see anything about this in the official WM_MOUSEWHEEL info from Microsoft.

Can you guys please confirm that single finger actions work as expected.

User avatar
KVRian
1288 posts since 4 Oct, 2012 from Utah

Post Mon Apr 19, 2021 4:12 am

Ah you're doing OS-level hooks. This may be of use: https://docs.microsoft.com/en-us/window ... scrollbars

On Windows I've had no issues with single finger gestures. I've only ever had issues with multi-finger gestures on Windows (I wish I could test in depth but I've given away my Windows laptop to a friend as my work provided me with my own MacBook).

Edit: My apologies if I'm over stepping, just trying to help provide information and help :hug:

User avatar
KVRAF
10972 posts since 24 Jun, 2008 from Europe

Post Mon Apr 19, 2021 7:51 pm

Thx :tu:

KVRer

Topic Starter

4 posts since 3 May, 2019

Post Tue Apr 20, 2021 6:51 am

Yeah, I have no single finger issues with my trackpad on mulab.

User avatar
KVRAF
10972 posts since 24 Jun, 2008 from Europe

Post Tue Apr 20, 2021 10:20 am

Ok, good to hear. I'll leave it as is now. Please don't use multi-touch yet in MuLab as it's not yet supported. I'm interested to research it later at appropriate time.

Return to “MUTOOLS”