[Feature Request] Hi-res scrolling

Feature Request Type

• Core functionality
• Add-on hardware support (eg. audio, RGB, OLED screen, etc.)
• Alteration (enhancement/optimization) of existing feature(s)
• New behavior

Description

Windows and Linux support a "resolution modifier" report for scrolling, which allows finer scrolling instead of just "ticks." Specifically, one can do smooth per-pixel scrolling. It also seems to use fewer resources, possibly because of the larger descriptors.

Unfortunately, it seems that there's virtually no public code or documentation available. The following is everything I've managed to gather in terms of documentation and examples:

• wheel.docx (Enhanced Wheel Support in Windows)
• our_descriptor.cc (from https://github.com/jfedor2/hid-remapper)
• HID: input: use the Resolution Multiplier for high-resolution scrolling (from the Linux kernel)

This almost certainly requires MOUSE_EXTENDED_REPORT to be enabled based on my testing.

I started mocking up something here: https://github.com/b-/qmk_firmware/tree/resolution_multiplier

However this is the first time I've ever gotten this close to USB or to HID descriptors.

I haven't tested my above code yet, either, though I will as soon as I get the chance.

Anyway, I'm posting this here to help me keep track of this, and of my progress (or lack thereof). I expect to edit this post frequently.