zoomies

momentum scrolling for touchpads on wlroots-based wayland compositors. very tuneable!
made this because other projects i've tried inject wheel-scroll events rather than finger-scroll ones which a lot of apps don't seem to handle well.

compatibility

zoomies injects scroll through zwlr_virtual_pointer, a wlroots protocol. so it works on wlroots-based compositors:

• hyprland (tested)
• sway, river, wayfire, labwc, and other wlroots compositors (expected, not yet confirmed)

it does not work on gnome (mutter) or kde (kwin), which don't implement that protocol. (feel free to open a pull request!)

install

nix (flakes)

add zoomies to your flake inputs:

{
    inputs = {
        nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";

        zoomies = {
            url = "github:csutora/zoomies";
            inputs.nixpkgs.follows = "nixpkgs";
        };
    };

    outputs = { self, nixpkgs, zoomies, ... }: {
        nixosConfigurations.your-hostname = nixpkgs.lib.nixosSystem {
            modules = [
                zoomies.nixosModules.default
                {
                    services.zoomies.enable = true;
                }
            ];
        };
    };
}

the module runs zoomies as a user service in your graphical session.

your user needs read access to the touchpad's /dev/input/eventN. on most distros that means being in the input group:

users.users.your-username.extraGroups = [ "input" ];

then relog (or reboot) for the group to take effect.

manual

git clone https://github.com/csutora/zoomies
cd zoomies
cargo build --release
./target/release/zoomies --help

run it inside your wayland session (it needs WAYLAND_DISPLAY), and make sure you can read the touchpad's /dev/input/eventN (be in the input group, or grant access some other way). then launch it from your compositor's autostart or a user service.

configuration

every option, with its default:

services.zoomies = {
    enable = true;

    deviceName = "Magic Trackpad"; # substring of the touchpad's name to match
    multiplier = 0.1;              # scroll distance per flick
    decayMs = 325.0;               # glide time
    minVelocity = 200.0;           # how hard a flick must be to start momentum
    stopThreshold = 40.0;          # speed at which the glide stops
    tickMs = 8;                    # ms between emitted scroll frames
    naturalScroll = true;          # follow natural scroll direction
};

the same knobs are available as flags for the manual setup, see zoomies --help.

if momentum feels off, multiplier (distance) and decayMs (length) are the first things you likely want to experiment with.

license

mit