In this simple programme, we animate an ellipse to always chase the mouse. The ellipse only ever moves a percentage of the distance between it and the mouse in each step.
The PVector object is used to handle the coordinates and the simple math operations.
PVector pos;
PVector targetPos;
float easingFactor = 0.1;
void setup() {
size(800, 600);
fill(0);
pos = new PVector();
targetPos = new PVector();
}
void draw() {
background(255);
targetPos.set(mouseX,mouseY);
targetPos = PVector.sub(targetPos, pos); // find the distance between mouse and position on the x an y axis
targetPos = PVector.mult(targetPos, easingFactor); // multiply the distance by the easingFactor to slow it down
if(targetPos.mag() > .5) {
//magnitude is always an absolute number, so we don't need to use the abs() function
pos = PVector.add(pos,targetPos);
}
ellipse(pos.x, pos.y, 60, 60);
}