[GUI Engine] Scrollspeed not scaling with resolution changes

[Hitcher]

Bug report

Describe the bug

The <scrollspeed>..</scrollspeed> tag doesn't scale with different resolutions like other tags (eg width, height, etc) resulting in uneven scrolling when using a resolution different to a skin's default.

Expected Behavior

The scroll speed should scale and remain constant at differing resolutions.

Actual Behavior

When using a different resolution to the one a skin uses as its default you either get faster scrolling for lower resolutions, or slower scrolling for higher resolutions.

Possible Fix

To Reproduce

Steps to reproduce the behavior:

1. Drop the Custom_1111_Scrollspeed_Test.xml into Estuary's xml folder
2. Navigate to System Settings
3. Observe the label scrolling speed at various resolutions

Custom_1111_Scrollspeed_Test.zip

Debuglog

The debuglog can be found here:

Screenshots

Here are some links or screenshots to help explain the problem:

Additional context or screenshots (if appropriate)

Here is some additional context or explanation that might help:

1920x1080 correct scrolling of 1000 pixels/second (1 label length per second)

1080.mp4

1280x720 scrolling is too fast as it's still using 1000 pixels/second when it should be 666 pixels/second

720.mp4

3840x2160 scrolling is too slow as it's still using 1000 pixels/second when it should be 2000 pixels/second

2160.mp4

Your Environment

Used Operating system:

• Android

• iOS

• tvOS

• Linux

• macOS

• Windows

• Windows UWP

• Operating system version/name:

• Kodi version:
  Omega v21

note: Once the issue is made we require you to update it with new information or Kodi versions should that be required.
Team Kodi will consider your problem report however, we will not make any promises the problem will be solved.

[Hitcher]

@jurialmunkey @jjd-uk can you confirm you get the same behaviour?