Slowing down mouse

Processing Coding Questions
1

Hello,
I wanted to make an ellipse that would follow the mouse but slowed down. Can anyone tell me why my code doesn’t work?

float x, y;
float speed = 7;

void setup() {
  size(1000,1000);
  smooth();
  frameRate(30);
}

void draw() {
  background(255);
  float distance = dist(x, y, mouseX, mouseY);
  float speedx = (mouseX - x) / distance * speed;
  float speedy = (mouseY - y) / distance * speed;
  x += speedx;
  y += speedy;
  fill(0);
  ellipse(x, y, 20, 20);
}
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2

Remove that / distance and set speed to some value between 0 and 1 (0.2 for example). Then your code should work perfectly!

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3

Another option: it is common to use linear interpolation – lerp – to move a value a percentage of the way towards another, as with a following / chasing object.

x = lerp(x, mouseX, 0.25);
y = lerp(y, mouseY, 0.25);

https://processing.org/reference/lerp_.html

or

PVector pv;
// ...
pv.lerp(new PVector(mouseX,mouseY), 0.25);
ellipse(pv.x, pv.y, 20, 20);

https://processing.org/reference/PVector_lerp_.html

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