/**
 * Scope demonstration.
 *
 * <p>Elie Zananiri<br>
 * CART 253, Winter 2008</p>
 */

// global variables, accessible throughout the program
int circleSize = 25; 

void setup() {
  size(400, 400);
  smooth();
  background(255);
  stroke(0);
  
  // xPos and yPos are local variables
  int xPos = 200;
  int yPos = 100;
  circle(xPos, yPos);
  
  fill(255, 0, 0);
  ellipse(width/2, height/2, circleSize, circleSize);
}

void draw() {
  // mouseX and mouseY are global built-in variables
  circle(mouseX, mouseY);
}

// x and y are local variables passed as parameters
void circle(int x, int y) {
  // fillColor is a local variable
  int fillColor = 255;
  
  fill(fillColor);
  ellipse(x, y, circleSize, circleSize);
}