hypr-dynamic-cursors/README.md

# hypr-dynamic-cursors
This plugin makes your cursor more realistic by simulating how it would behave if it was an actual object being dragged across your screen. This means that your cursor can change based on how it is used, e.g. tilt in the direction you are moving or straight out rotate towards it.

Why did I implement this again?

## showcase
The plugin supports two different modes, `rotate` and `tilt`. They both are customizable and have a different base behaviour.

#### rotate
In this mode, the cursor is simulated as a stick which is dragged across the screen on one end. This means it will rotate towards the movement direction, and feels really realistic.

https://github.com/VirtCode/hypr-dynamic-cursor/assets/41426325/ccd6d742-8e2b-4073-a35e-318c7e19705c

#### tilt
In this mode, the cursor is tilted based on the X direction and speed it is moving at. It was intended to simulate how an object would be affected by air drag, but implemented is only a rough approximation. This mode can also be customized extensively with different activation functions.

https://github.com/VirtCode/hypr-dynamic-cursors/assets/41426325/ae25415c-e77f-4c85-864c-2eedbfe432e3

## state
This plugin is still very early in its development. **Currently, only the `-git` version of hyprland is supported**. There are also multiple things which may or may not be implemented in the future:

- [X] software cursor rendering
- [X] hardware cursor rendering (as far as possible with wlroots)
- [X] stick simulation
- [X] air drag simulation
- [ ] pendulum simulation
- [ ] per-shape length and starting angle (if possible)

If anything here sounds interesting to you, don't hesitate to contribute.

Please note that this plugin was created more or less as a joke. I mainly wanted to see how using a rotating or tilted cursor was like. So I will not guarantee any future updates and bugfixes.

## installation
Installation is supported via `hyprpm`. Supported hyprland versions are `v0.42.0` (yet unreleased) and upwards. The main branch generally tries to target `-git`.

```sh
hyprpm add https://github.com/virtcode/hypr-dynamic-cursors
hyprpm enable dynamic-cursors
```

Compatibility with other plugins is not guaranteed. It probably should work with most plugins, unless they also change your cursor's behaviour. It will however work with any cursor theme.

## configuration
This plugin can be configured in its dedicated configuration section (`plugin:dynamic-cursors`). The default values are shown below.
```ini
plugin:dynamic-cursors {

    # enables the plugin
    enabled = true

    # sets the cursor behaviour, supports these values:
    # tilt   - tilt the cursor based on x-velocity
    # rotate - rotate the cursor based on movement direction
    mode = tilt

    # minimum angle difference in degrees after which the shape is changed
    # smaller values are smoother, but more expensive for hw cursors
    threshold = 2

    # for mode = rotate
    rotate {

        # length in px of the simulated stick used to rotate the cursor
        # most realistic if this is your actual cursor size
        length = 20
    }

    # for mode = tilt
    tilt {

        # controls how powerful the tilt is, the lower the more power
        # this value controls at which speed (px/s) the full tilt is reached
        limit = 5000

        # relationship between speed and tilt, supports these vaules:
        # linear             - a linear function is used
        # quadratic          - a quadratic function is used (most realistic to actual air drag)
        # negative_quadratic - negative version of the quadratic one, feels more aggressive
        function = negative_quadratic
    }
}
```

## performance
Depending on your hyprland configuration, this plugin can have a different performance impact. It mainly depends on whether you are using software or hardware cursors:

**Software Cursors**: No (additional) performance impact. <br>
Rotating the cursor can be done in the same draw call that is used to draw the cursor anyways, so there is no additional performance impact. Note however that software cursors in of themselves are not really efficient.

**Hardware Cursors**: Medium performance impact. <br>
To rotate the cursor smoothly, the cursor shape needs to be changed quite often. This is not exactly compatible with how hardware cursors are intended to work. With this plugin, the overhead of changing the cursor shape can be noticed more often, making it use more resources. Compared to normal hardware cursors, there is a big performance hit, but it is still more efficient than using software cursor though.

The plugin also has a base performance impact, which is practically zero when mode is `rotate` and still low if it is `tilt`.

## development
To work on this plugin, you can clone this repository and use the Makefile to build it. I suggest opening a nested Hyprland session, and loading the plugin there:

```sh
make load
```

If you want to debug hardware cursors, this plugin also has an additional configuration option, `plugin:dynamic-cursors:hw_debug` which when true will show where the whole cursor buffer is, and also shows when it is updated.

Also make sure you disable the plugin on your host session, otherwise your cursor will be rotated twice.

## license
This plugin is licensed under the MIT License. Have a look at the `LICENSE.md` file for more information.