Checkerboard with Checkers

Problem: Enhance the Checkerboard problem so that it centers the checkerboard horizontally and draws the set of red and black checkers corresponding to the initial state of the game. (Roberts ch 4, Exercise 14)

2 instances of repeated code here. We want red checkers apply to the first three rows, no checkers to apply to the middle rows, and white checkers apply to the last three rows. We can take care of this by changing the outer while loop; instead of i going from 0 to N_ROWS, we break it up into a) 0 to 3, b) 3 to N_ROWS-3, and c) N_ROWS-3 to N_ROWS. I need to think about how to break up my iterations this way without repeating code too much.

In the rows where checkers do apply, we want to add checkers only to the squares that are filled in. We have a boolean that says "If the sum of the column number and the row number is odd, then it should be filled in." This is how we make sure the "Every Other" applies both horizontally and vertically. We want to same boolean to apply to whether we put checkers down or not; however, if we make the line "add(sq)" come after the "add(redChecker)", we won't see the checker. But we can't make it come after while being in the same loop because we want to add the square whether or not it's a filled-in square.

I'm going to sleep now...this will be easier to clean up in the morning.

import acm.graphics.*;

/*
* File: CheckerboardWithCheckers.java
* Name: Chu
* Section Leader: Geoff clearly, because without him there would be no acm.jar in this Eclipse workspace, and then where would we be?
* ------------------
*
*/
import acm.graphics.*;
import acm.program.*;
import java.awt.*;

public class CheckerboardWithCheckers extends GraphicsProgram {

 public void run() {
  double sqSize = (double) getHeight() / N_ROWS;
  double boardWidth = N_COLUMNS * sqSize;
  for (int i = 0; i < 3; i++) {
   for (int j = 0; j < N_COLUMNS; j++) {
    double x = (j * sqSize) + (getWidth()/2 - boardWidth/2);
    double y = i* sqSize;
    GRect sq = new GRect(x, y, sqSize, sqSize);
    if ((i+j) % 2 != 0) {
     sq.setFilled(true);

     
    }
    add(sq);
    
    if ((i+j) % 2 != 0) {//This is bad, kids! Don't repeat code
     GOval redChecker = new GOval (x, y, sqSize, sqSize);
     redChecker.setFilled(true);
     redChecker.setFillColor(Color.RED); 
     add(redChecker);
    }
   } 
  }
  
  for (int i = 3; i < N_ROWS-3; i++) { //This is bad, kids! Don't repeat code
   for (int j = 0; j < N_COLUMNS; j++) {
    double x = (j * sqSize) + (getWidth()/2 - boardWidth/2);
    double y = i* sqSize;
    GRect sq = new GRect(x, y, sqSize, sqSize);
    if ((i+j) % 2 != 0) {
     sq.setFilled(true);
     
    }
    add(sq);
   
   } 
  }
  
  for (int i = N_ROWS-3; i < N_ROWS; i++) {
   for (int j = 0; j < N_COLUMNS; j++) {
    double x = (j * sqSize) + (getWidth()/2 - boardWidth/2);
    double y = i* sqSize;
    GRect sq = new GRect(x, y, sqSize, sqSize);
    if ((i+j) % 2 != 0) {
     sq.setFilled(true);
     
    }
    add(sq);
    
    if ((i+j) % 2 != 0) {//This is bad, kids! Don't repeat code
     GOval whiteChecker = new GOval (x, y, sqSize, sqSize);
     whiteChecker.setFilled(true);
     whiteChecker.setFillColor(Color.WHITE); 
     add(whiteChecker);
    }
   } 
  }
 }
 


//private constants
 private static final int N_ROWS = 8;
 private static final int N_COLUMNS = 8;

What it looks like: