How to Add Mouse Movement Smoothing

Adding Mouse Movement Smoothing

By default, the mouse "teleports" from point A to point B, which is not always the desired behavior. This is where "smoothers" come to the rescue - tools that can plan mouse movement based on some logic. The algorithm itself can vary. By default, the program includes algorithms from BenLand (BenLandUserInputSmoother) and Kalon (KalonUserInputSmoother). These algorithms have some parameters that you can adjust, but even by default, the program includes several presets, here are the most useful ones:

BenLandLinearFast - moves the mouse from point A to point B in a straight line
BenLandRandomizedFast - adds some deviation at the starting point of the trajectory
MlHumanMouseV1 - ML Human Move smoother. Predicts compact movement parameters from a local model pack and runs at the default 2x ML timing.
MlHumanMouseFastV1 - ML Human Move Fast smoother. Uses the same model-backed route planner with 4x ML timing.

By specifying InputSmootherId in the code, you can instruct the simulator to smooth out mouse movements

ISendInputUnstableScriptingApi SendInput { get; } = GetService<ISendInputUnstableScriptingApi>(); // needed for input sending
SendInput.InputSmootherId = "MlHumanMouseV1"; // or "MlHumanMouseFastV1"

Example where we implement our own smoothing

You can import the ready-made example from here: https://eyeauras.net/share/S20240701201856mfdkUQbqEY1k

Create an aura with a script
Copy-paste, run it, if everything is fine - the script will move the mouse to the center of the screen with a visible delay and smoothly enough

using EyeAuras.Roxy.Services;

ISendInputUnstableScriptingApi SendInput { get; } = GetService<ISendInputUnstableScriptingApi>(); // needed for input sending

var customSmoother = new CustomInputSmoother();
GetService<IUserInputSmootherRegistrator>() // get the service responsible for our "smoothers"
    .Register(customSmoother); // and add ours

// now tell the API to use our smoother
SendInput.InputSmootherId = customSmoother.Id; // or something like "MlHumanMouseV1";

var screenSize = System.Windows.Forms.SystemInformation.PrimaryMonitorSize; // get the size of the primary screen

Log.Info($"Primary monitor size: {screenSize}");
SendInput.MouseMoveTo(screenSize.Width / 2, screenSize.Height / 2); // move to the center
Log.Info($"Movement completed, cursor is at: {SendInput.CursorPosition}");

/// <summary>
/// This class contains the essence of our smoother.
/// It adds NumberOfPoints points between the starting and ending points of movement.
/// A "real" smoother can use things like Bezier curves or any other logic
/// </summary>
class CustomInputSmoother : IUserInputSmoother
{
    public string Id { get; init; } = "MySmoother";

    public string Name { get; init; } = "This is my new cool input smoother";

    public int NumberOfPoints { get; init; } = 20;

    public TimeSpan DelayBetweenPoints { get; init; } = TimeSpan.FromMilliseconds(10);

    public IReadOnlyList<MouseInput> Generate(
        Point startPosition,
        Point targetPosition)
    {
        var inputs = new List<MouseInput>();

        // thanks to ChatGPT for some code for approximating points on a line
        for (int i = 0; i <= NumberOfPoints; i++)
        {
            var t = (float)i / NumberOfPoints;

            var x = (int)(startPosition.X * (1 - t) + targetPosition.X * t);
            var y = (int)(startPosition.Y * (1 - t) + targetPosition.Y * t);

            var input = new MouseInput(new Point(x, y), DelayBetweenPoints);
            inputs.Add(input);
        }

        return inputs;

    }
}