// this defines a class
public class Starfield {
  private Star stars[];
  private int count;
  
  //  this is the class constructor called when an object of this class is created
  public Starfield( int count ) {
    // This sets the class property 'count' to the value of the parameter in the constructor which is also referenced as 'count'.  This is perfectly valid, but you need to include 'this.' to reference the class count property rather than the parameter.
    this.count = count;*
    stars = new Star[count];
    // a for loop is usually repeated the number of times set by the value of limit - in this case 'count'.
    for ( int i =0; i < count; i++) {*
        // a new star object is created each time the loop is repeated
	stars[i] = new Star( random( width ), random( height ), random( 10 ));*
    }
  }
  
  public void draw() {
    strokeWeight( 2 );
    for ( int i =0; i < count; i++) {*
	stroke( stars[i].z * 25 );*
	point( stars[i].x, stars[i].y );*
    
	stars[i].x -= stars[i].z;*
	if (stars[i].x < 0) { *
	  stars[i] = new Star( width, random( height ), sqrt(random( 100 )));
	}
    }
  }
}

class Star {
  float x, y, z;
  Star( float x, float y, float z ) {
    this.x = x;
    this.y = y;
    this.z = z;
  }
}