InertPad

An experiment that adds inertia to touchpad on Linux.

It listens to raw (evdev) touchpad events, and creates additional virtual mouse device (via uinput) which kicks in to drive the pointer only during inertial movement. It doens't alter nor inhibits the original touchpad events.

Build

1. Install Rust
2. Build:

cargo build --release

Usage

It requires root access. It needs read-access to /dev/input/evdev* for reading raw touchpad events, and write-access to /dev/uinput to create a virtual mouse device. For the former adding a user to input group is sufficient, but the latter requires root access anyway.

sudo ./target/release/inertpad

It can be configured with the following command-line arguments:

• --drag <DRAG> - Inertia drag coefficient (must be between 0.0 and 1.0) Affects inertial movement deceleration. Default: 0.15.
• --speed-factor <SPEED_FACTOR> - Scales velocity from raw touchpad units to virtual mouse units. Affects initial inertial movement speed. Default: 0.0075.
• --speed-threshold <SPEED_THRESHOLD> - Minimum touchpad pointer speed required to trigger inertial movement. Increase if a short tap causes unwanted pointer movement. Decrease if intentional swipes don't trigger inertial movement. Default: 1000.
• --refresh-rate <REFRESH_RATE> - Pointer position refresh rate during inertial movement. Default: 60.
• --multitouch-cooldown <MULTITOUCH_COOLDOWN> - Prevents inertial movement from multitouch by ignoring swipes for a specified number of milliseconds after multitouch release. Default: 500.