var foodX = 300;

var x = 200;

var y = 200;

var amount = 10;

var scope= 30;

var size = 30;

var limit = 100;

function setup() {

  createCanvas(400, 400);

  noStroke();

  frameRate(60);

}

​

function draw() {

  background(220);

  if(mouseIsPressed){

    foodX = mouseX;

    foodY = mouseY;

    size = 30;

  }

  fill(255);

  ellipse(foodX,foodY,size,size);

  fill(0,200,0);

  ellipse(x,y,scope,scope);

  if(foodX == x && foodY == y && size > 0){

    scope++;

    size--;

  }

  if(foodX > x){

    x++;

  }

  if(foodX < x){

    x--;

  }

  if(foodY > y){

    y++;

  }

  if(foodY < y){

    y--;

  }

}