an explaination please!

**sweetjava** · 07-23-2009, 02:19 AM

:confused:

Can someone please explain to me where they are getting the cx, cy values from. As far as I can tell they are never definied as values other then cx, cy.

I know this is probably the most retarded question in the history of time, but if you can explain it to me I would be very happy.

Java Code:

/* File: RobotFace.java                  */ 
/* This program draws a robot face.      */ 
 
import acm.graphics.*; 
import acm.program.*; 
import java.awt.*; 
 
public class tictac extends GraphicsProgram { 
 
/* Parameters for the drawing */ 
 private static final int HEAD_WIDTH = 100; 
 private static final int HEAD_HEIGHT = 150; 
 private static final int EYE_RADIUS = 10; 
 private static final int MOUTH_WIDTH = 60; 
 private static final int MOUTH_HEIGHT = 20; 
 
 public void run() { 
  addFace(getWidth() / 2, getHeight() / 2); 
 } 
 
/* Adds the entire face centered at (cx, cy) */ 
 private void addFace(double cx, double cy) { 
  addHead(cx, cy); 
  addEye(cx - HEAD_WIDTH / 4, cy - HEAD_HEIGHT / 4); 
  addEye(cx + HEAD_WIDTH / 4, cy - HEAD_HEIGHT / 4); 
  addMouth(cx, cy + HEAD_HEIGHT / 4); 
 } 
 
/* Adds the head centered at (cx, cy) */ 
 private void addHead(double cx, double cy) { 
  double x = cx - HEAD_WIDTH / 2; 
  double y = cy - HEAD_HEIGHT / 2; 
  GRect head = new GRect(x, y, HEAD_WIDTH, HEAD_HEIGHT); 
  head.setFilled(true); 
  head.setFillColor(Color.GRAY); 
  add(head); 
 } 
 
/* Adds an eye centered at (cx, cy) */ 
 private void addEye(double cx, double cy) { 
  double x = cx - EYE_RADIUS; 
  double y = cy - EYE_RADIUS; 
  GOval eye = new GOval(x, y, 2 * EYE_RADIUS, 2 * EYE_RADIUS); 
  eye.setFilled(true); 
  eye.setColor(Color.YELLOW); 
  add(eye); 
 } 
 
/* Adds a mouth centered at (cx, cy) */ 
 private void addMouth(double cx, double cy) { 
  double x = cx - MOUTH_WIDTH / 2; 
  double y = cy - MOUTH_HEIGHT / 2; 
  GRect mouth = new GRect(x, y, MOUTH_WIDTH, MOUTH_HEIGHT); 
  mouth.setFilled(true); 
  mouth.setColor(Color.WHITE); 
  add(mouth); 
 } 
}