please help me with this...

I have this code which is following my mouse pointer quite smoothly, now I want to replace the mouse pointer with my tracked face.....please guide me with how to do it


float gravity = -7.0;
float mass = 10.0;
int numsprings = 5;
 
ArrayList springs;
 
void setup()
{
  size(1024, 768);
  smooth();
  fill(255, 255, 0);
  noStroke();
 
  springs = new ArrayList();
  for (int i=0; i<numsprings; i++) {   // make 5 boxes
    springs.add(new Spring2D(0, 0, mass, gravity));  // tell x, y position, mass and gravity
  }
}
 
void draw()
{
  background(40); 
  Spring2D firstspring = (Spring2D) springs.get(0);   // get position of the first box
  firstspring.update(mouseX, mouseY);   //  update the position of box one
  firstspring.display(mouseX, mouseY);
 
  for (int i=1; i<springs.size(); i++) {
    Spring2D spring = (Spring2D) springs.get(i);
    Spring2D backspring = (Spring2D) springs.get(i-1);
    spring.update(backspring.x, backspring.y);
    spring.display(backspring.x, backspring.y);
  }
}

class Spring2D {
  float vx, vy; // The x- and y-axis velocities
  float x, y; // The x- and y-coordinates
  float gravity;
  float mass;
  float radius = 10;
  float stiffness = 0.3;
  float damping = 0.7;
  
  Spring2D(float xpos, float ypos, float m, float g) {
    x = xpos;
    y = ypos;
    mass = m;
    gravity = g;
  }
  
  void update(float targetX, float targetY) {
    float forceX = (targetX - x) * stiffness;
    float ax = forceX / mass;
    vx = damping * (vx + ax);
    x += vx;
    float forceY = (targetY - y) * stiffness;
    forceY += gravity;
    float ay = forceY / mass;
    vy = damping * (vy + ay);
    y += vy;
  }
  
  void display(float nx, float ny) {
    rect(x, y, 40, 20);
  }
}

thanks in advance