Hi all,

I'm not too sure how to word my question so I'll try keep it simple. Basically, I'm trying to get the distance between two ellipses that share the same class. A single ellipse is created in the 'display' method, so any instance of the class will share the same x and y coordinates.  So at the moment I don't know what I should be plugging in for the x2 and y2 points of my distance formula because they are not defined. I could solve my problem by making another ellipse in the display method with different x,y variables but then I would have to implement my 'moveBall method etc to accommodate the new variables, which I don't want to do. So the way I have defined the class using a single ellipse I now don't know what I should be plugging in for the x2 and y2 coordinates of the distance formula located in the 'collision' method.

Hope that sort of make sense? I'm sure their is a simple logical solution I'm not seeing.

1. color c = color(255, 0, 0);
   color c2 = color(0, 255, 0);
   Ball ballOne = new Ball(50, 250);
   Ball ballTwo = new Ball(950, 250);
   
   void setup() {
     background(0);
     size(1000, 500);
     smooth();
     ellipseMode(CENTER);
     frameRate(60);
   }
   
   void draw()
   {
     background(0);
     ballOne.display(c);
     ballOne.moveBall(); 
     ballTwo.display(c);
     ballTwo.moveBall();
     if (ballOne.collide(ballTwo))
     {
       fill(c2);
     }
     else
     {
       fill(c);
     }
     if (frameCount % 60 == 0)
     {
       println(frameRate);
     }
   }
   
   class Ball {
     int dia;
     int x, y; 
     int speedX;
     int speedY;
     Ball(int x_, int y_)
     {
       x = x_;
       y = y_;
       dia = 100;
       speedX = 6;
       speedY = 1;
     }
     void display(color cAll)
     {
       noStroke();
       fill(cAll);
       ellipse(x, y, dia, dia);
     }
     void moveBall()
     {
       x = x + speedX;
       if (x > width - dia/2)
       {
         speedX = -abs(speedX);
       }
       if (x < 0 + dia/2)
       {
         speedX = abs(speedX);
       }
     }
     boolean collide(Ball b)
     {
       //How do i get the x2 and y2 coordinates for the second instance of Ball
       float distance = sqrt (pow(x - x2, 2) + pow(y - y2, 2));  // < --------- ?!?!
       println("This is distance: " + distance);
       if (distance < ((b.dia/2) + dia/2))
       {
         return true;
       }
       return false;
     }
   }