PenDragScroll.macOS

An OpenTabletDriver plugin for macOS that turns a pen button into a hold-to-scroll modifier. While the modifier is active, pen movement is converted into high-resolution mouse wheel scrolling instead of normal cursor movement.

Features

• Hold pen button → drag to scroll – natural, expressive scrolling
• Anchor cursor – optionally lock the cursor in place while scrolling (or let it move freely)
• Axis lock – snap to horizontal/vertical scrolling when movement is predominantly along one axis
• High-resolution scrolling – smooth per-pixel scroll events (macOS-native)
• Configurable sensitivity – vertical/horizontal units per pixel, invert, threshold

Installation

1. Copy PenDragScroll.dll and metadata.json into:

   ~/Library/Application Support/OpenTabletDriver/Plugins/PenDragScroll/
   

2. Restart OpenTabletDriver
3. In ODT settings, add the Pen Drag Scroll filter and assign Pen Drag Scroll Toggle binding to a pen button

Default binding (Button 2)

{
  "Path": "PenDragScroll.Bindings.PenDragScrollToggleBinding",
  "Settings": [],
  "Enable": true
}

Configuration parameters

Property	Default	Description
AnchorCursor	true	Lock cursor position while scrolling
VerticalUnitsPerPixel	30	Vertical scroll units per pixel of pen movement
HorizontalUnitsPerPixel	0	Horizontal scroll units per pixel (0 = disabled)
InvertVertical	false	Invert vertical scroll direction
InvertHorizontal	false	Invert horizontal scroll direction
AxisLockEnabled	true	Snap to dominant axis
AxisLockThreshold	10	Pixels before axis lock engages
AxisLockRatio	2.0	Dominant axis must be this many times stronger

Build

dotnet build -c Release

Requires .NET 8 SDK and OpenTabletDriver installed.

Credits

Inspired by soestin/PenDragScrollPlugin — macOS port with native high-resolution scrolling via Core Graphics.