C# moving the mouse around realistically

Question

I am demoing a piece of software and want to build a mouse 'mover' function so that I can basically automate the process. I want to create realistic mouse movements but am having a bit of a mental block in the thought process. I can move a mouse around easily with c# but want it to be a bit more realistic than just the cursor appearing at a certain x, y, coordinates and then pressing a button.

I get the current position of the mouse and then get the end point. Calculate an arc between the two points, but then I need to calculate points along that arc so that I can add a timer event into that so that I can move from one point to the next, and then repeat this till I get to the target...

Anybody want to elaborate?

Thanks, R.

You move your mouse from point A to point B in an arc? I seem to go in a straight line. That would make your life a lot easier. :) — JP Alioto, May 27 '09 at 02:20
JP: unless you work with a ruler are all your mouse trails really straight lines? :) I am just thinking of ways of making the mouse move in realistic ways using code. I have googled, looking for a code base but it is something that is not really done. — flavour404, May 27 '09 at 19:58
Could you tell me how you make the mouse click? I'm using C# in Visual Studio 2010 — BlueCacti, Apr 02 '12 at 13:52

Erik Forbes · Accepted Answer · 2012-08-01T13:05:00.013

24

I tried the arc calculation method, turned out to be far to complex and, in the end, it didn't look realistic. Straight lines look much more human, as JP suggests in his comment.

This is a function I wrote to calculate a linear mouse movement. Should be pretty self-explanatory. GetCursorPosition() and SetCursorPosition(Point) are wrappers around the win32 functions GetCursorPos and SetCursorPos.

As far as the math goes - technically, this is called Linear Interpolation of a line segment.

public void LinearSmoothMove(Point newPosition, int steps) {
    Point start = GetCursorPosition();
    PointF iterPoint = start;

    // Find the slope of the line segment defined by start and newPosition
    PointF slope = new PointF(newPosition.X - start.X, newPosition.Y - start.Y);

    // Divide by the number of steps
    slope.X = slope.X / steps;
    slope.Y = slope.Y / steps;

    // Move the mouse to each iterative point.
    for (int i = 0; i < steps; i++)
    {
        iterPoint = new PointF(iterPoint.X + slope.X, iterPoint.Y + slope.Y);
        SetCursorPosition(Point.Round(iterPoint));
        Thread.Sleep(MouseEventDelayMS);
    }

    // Move the mouse to the final destination.
    SetCursorPosition(newPosition);
}

edited Aug 01 '12 at 13:05

answered May 27 '09 at 02:35

Erik Forbes

35,357
27
98
122

3

I knew somebody would be smart with the math! :) – JP Alioto May 27 '09 at 06:00
Erik, I thought I replied to this last night but obviously I was more tired than I thought. Thanks, its a great answer and definitely gives me a) something I can use, b) something I can expand on. Great answer. I'll bear in mind what you said about the arc. – flavour404 May 27 '09 at 19:56
No worries. Glad to help. I'll see if I can dig up the old code I wrote that used arcs and post it if I find it. – Erik Forbes May 28 '09 at 00:31
@Erik, What's MouseEventDelayMS? – Ashley Simpson Sep 29 '09 at 18:26
Sorry - an int constant that determines the number of milliseconds to wait in between move events. – Erik Forbes Sep 29 '09 at 20:52
Do you lose accuracy because of the rounding? When I draw a line on the screen and tried to move the mouse along it the mouse doesn't move exactly on that line. – gonzobrains Mar 08 '13 at 05:49
Yes, but I didn't need an exact solution. – Erik Forbes Apr 01 '13 at 14:32

Coder1095 · Answer 2 · 2012-12-08T14:40:15.980

I converted the WindMouse function mentioned earlier into C# and it is actually pretty realistic. Note that this is just a rough sample and does not use wrappers for GetCursorPos and SetCursorPos. I will be using the Windows Input Simulator wrappers.

static class SampleMouseMove {

    static Random random = new Random();
    static int mouseSpeed = 15;

    static void Main(string[] args) {
        MoveMouse(0, 0, 0, 0);
    }

    static void MoveMouse(int x, int y, int rx, int ry) {
        Point c = new Point();
        GetCursorPos(out c);

        x += random.Next(rx);
        y += random.Next(ry);

        double randomSpeed = Math.Max((random.Next(mouseSpeed) / 2.0 + mouseSpeed) / 10.0, 0.1);

        WindMouse(c.X, c.Y, x, y, 9.0, 3.0, 10.0 / randomSpeed,
            15.0 / randomSpeed, 10.0 * randomSpeed, 10.0 * randomSpeed); 
    }

    static void WindMouse(double xs, double ys, double xe, double ye,
        double gravity, double wind, double minWait, double maxWait,
        double maxStep, double targetArea) {

        double dist, windX = 0, windY = 0, veloX = 0, veloY = 0, randomDist, veloMag, step;
        int oldX, oldY, newX = (int)Math.Round(xs), newY = (int)Math.Round(ys);

        double waitDiff = maxWait - minWait;
        double sqrt2 = Math.Sqrt(2.0);
        double sqrt3 = Math.Sqrt(3.0);
        double sqrt5 = Math.Sqrt(5.0);

        dist = Hypot(xe - xs, ye - ys);

        while (dist > 1.0) {

            wind = Math.Min(wind, dist);

            if (dist >= targetArea) {
                int w = random.Next((int)Math.Round(wind) * 2 + 1);
                windX = windX / sqrt3 + (w - wind) / sqrt5;
                windY = windY / sqrt3 + (w - wind) / sqrt5;
            }
            else {
                windX = windX / sqrt2;
                windY = windY / sqrt2;
                if (maxStep < 3)
                    maxStep = random.Next(3) + 3.0;
                else
                    maxStep = maxStep / sqrt5;
            }

            veloX += windX;
            veloY += windY;
            veloX = veloX + gravity * (xe - xs) / dist;
            veloY = veloY + gravity * (ye - ys) / dist;

            if (Hypot(veloX, veloY) > maxStep) {
                randomDist = maxStep / 2.0 + random.Next((int)Math.Round(maxStep) / 2);
                veloMag = Hypot(veloX, veloY);
                veloX = (veloX / veloMag) * randomDist;
                veloY = (veloY / veloMag) * randomDist;
            }

            oldX = (int)Math.Round(xs);
            oldY = (int)Math.Round(ys);
            xs += veloX;
            ys += veloY;
            dist = Hypot(xe - xs, ye - ys);
            newX = (int)Math.Round(xs);
            newY = (int)Math.Round(ys);

            if (oldX != newX || oldY != newY)
                SetCursorPos(newX, newY);

            step = Hypot(xs - oldX, ys - oldY);
            int wait = (int)Math.Round(waitDiff * (step / maxStep) + minWait);
            Thread.Sleep(wait);
        }

        int endX = (int)Math.Round(xe);
        int endY = (int)Math.Round(ye);
        if (endX != newX || endY != newY)
            SetCursorPos(endX, endY);
    }

    static double Hypot(double dx, double dy) {
        return Math.Sqrt(dx * dx + dy * dy);
    }

    [DllImport("user32.dll")]
    static extern bool SetCursorPos(int X, int Y);

    [DllImport("user32.dll")]
    public static extern bool GetCursorPos(out Point p);
}

score 3 · Answer 3 · edited May 05 '11 at 19:17

procedure WindMouse(xs, ys, xe, ye, gravity, wind, minWait, maxWait, maxStep, targetArea: extended);
var
  veloX, veloY, windX, windY, veloMag, dist, randomDist, lastDist, step: extended;
  lastX, lastY: integer;
  sqrt2, sqrt3, sqrt5: extended;
begin
  sqrt2:= sqrt(2);
  sqrt3:= sqrt(3);
  sqrt5:= sqrt(5);
  while hypot(xs - xe, ys - ye) > 1 do
  begin
    dist:= hypot(xs - xe, ys - ye);
    wind:= minE(wind, dist);
    if dist >= targetArea then
    begin
      windX:= windX / sqrt3 + (random(round(wind) * 2 + 1) - wind) / sqrt5;
      windY:= windY / sqrt3 + (random(round(wind) * 2 + 1) - wind) / sqrt5;
    end else
    begin
      windX:= windX / sqrt2;
      windY:= windY / sqrt2;
      if (maxStep < 3) then
      begin
        maxStep:= random(3) + 3.0;
      end else
      begin
        maxStep:= maxStep / sqrt5;
      end;
    end;
    veloX:= veloX + windX;
    veloY:= veloY + windY;
    veloX:= veloX + gravity * (xe - xs) / dist;
    veloY:= veloY + gravity * (ye - ys) / dist;
    if hypot(veloX, veloY) > maxStep then
    begin
      randomDist:= maxStep / 2.0 + random(round(maxStep) / 2);
      veloMag:= sqrt(veloX * veloX + veloY * veloY);
      veloX:= (veloX / veloMag) * randomDist;
      veloY:= (veloY / veloMag) * randomDist;
    end;
    lastX:= Round(xs);
    lastY:= Round(ys);
    xs:= xs + veloX;
    ys:= ys + veloY;
    if (lastX <> Round(xs)) or (lastY <> Round(ys)) then
      MoveMouse(Round(xs), Round(ys));
    step:= hypot(xs - lastX, ys - lastY);
    wait(round((maxWait - minWait) * (step / maxStep) + minWait));
    lastdist:= dist;
  end;
  if (Round(xe) <> Round(xs)) or (Round(ye) <> Round(ys)) then
    MoveMouse(Round(xe), Round(ye));
end;

{*******************************************************************************
procedure MMouse(x, y, rx, ry: integer);
By: Benland100
Description: Moves the mouse.
*******************************************************************************}
//Randomness is just added to the x,y. Might want to change that.
procedure MMouse(x, y, rx, ry: integer);
var
  cx, cy: integer;
  randSpeed: extended;
begin
  randSpeed:= (random(MouseSpeed) / 2.0 + MouseSpeed) / 10.0;
  if randSpeed = 0.0 then
    randSpeed := 0.1;
  getMousePos(cx,cy);
  X := x + random(rx);
  Y := y + random(ry);
  WindMouse(cx,cy,x,y,9.0,3.0,10.0/randSpeed,15.0/randSpeed,10.0*randSpeed,10.0*randSpeed);
end;

Here are some methods written in SCAR. Converting them C# shouldn't be too hard, these are quite realistic.

I have been trying to work out what the minE() function does, any idea? — flavour404, Jun 08 '09 at 20:19
@flavour404 - `minE()` Returns the smaller of two variables - `Math.Min()` or similar. Source: http://forums.freddy1990.com/index.php?topic=4214.0 — Erik Forbes, Aug 01 '12 at 13:08
Not sure how reliable the source is but judging from the code above I think it's accurate. — Erik Forbes, Aug 01 '12 at 13:09

score 1 · Answer 4 · answered Aug 08 '20 at 12:35

You can try this.

public static class Mouse
{
    private const float MOUSE_SMOOTH = 200f;

    public static void MoveTo(int targetX, int targetY)
    {
        var targetPosition = new Point(targetX, targetY);
        var curPos = Cursor.Position;

        var diffX = targetPosition.X - curPos.X;
        var diffY = targetPosition.Y - curPos.Y;

        for (int i = 0; i <= MOUSE_SMOOTH; i++)
        {
            float x = curPos.X + (diffX / MOUSE_SMOOTH * i);
            float y = curPos.Y + (diffY / MOUSE_SMOOTH * i);
            Cursor.Position = new Point((int)x, (int)y);
            Thread.Sleep(1);
        }

        if (Cursor.Position != targetPosition)
        {
            MoveTo(targetPosition.X, targetPosition.Y);
        }
    }
}

score 1 · Answer 5 · answered May 27 '09 at 02:34

1

A usual way, I think, is to physically move the real mouse with your own hand: and have the software capture those (real) movements, and replay them.

answered May 27 '09 at 02:34

ChrisW

54,973
13
116
224

1

I like this method, but it only work if you already know where the cursor have to go, if the program calculates the position during it's runtime this will not work. – Tortillas Jul 25 '19 at 13:51

C# moving the mouse around realistically

5 Answers5

Linked

Related