//Daniel Shiffman, Nature of Code, 3/1/2005
//http://stage.nyu.edu/nature

//a basic implementation of John Conway's Game of Life CA
//how could this be improved to use object oriented programming?
//think of it as similar to our particle system, with a "cell" class
//to describe each individual cell and a "cellular automata" class
//to describe a collection of cells

//int cellsize = 1;
//int COLS, ROWS;
//game of life board
int[] old_board, new_board;

void setup()
{
  size(200, 200);
  //smooth();
  //initialize rows, columns and set-up arrays
  //COLS = width/cellsize;
  //ROWS = height/cellsize;
  old_board = new color[width*height];
  new_board = new color[width*height];
  colorMode(RGB,255);
  background(0);
  //call function to fill array with random values 0 or 1
  initBoard();
  frameRate(3);
}

void draw()
{
  //background(100);

//loadPixels();
  //loop through every spot in our 2D array and check spots neighbors

  for (int x = 0; x < width;x++) {
    for (int y = 0; y < height;y++) {
            int nb = color(0);
      //Note the use of mod ("%") below to ensure that cells on the edges have "wrap-around" neighbors
      //above row
      int above = (y+height-1) % height;
      int below =  (y+1) % height; 
      
      int left = (x+width-1) % width;
      int right = (x+1) % width; 
      
     // Rug rules with wrap 
       nb = color(old_board[(left*width)+above]) +
            color(old_board[ (x*width) +above]) +
            color(old_board[(right*width)+ above]) +
      //middle row
            color(old_board[(left*width)+ y ]) +
            color(old_board[(right*width)+ y ]) +
      //bottom row
            color(old_board[(left*width)+below]) +
            color(old_board[(x*width)+below]) +
            color(old_board[(right*width)+below]);

    nb = color(nb/8) + color(1);
    
    //println(nb);
    
    
    /*
    float r = red(nb);
    float g = green(nb);
    float b = blue(nb); 
    
    r = red(nb)%256;
    g = green(nb)%256;
    b = blue(nb)%256;
    */

    
    new_board[(y*width)+x] = color(nb);//color(r,g,b);
    
    
    }
    
  }
  
  loadPixels();
  //RENDER game of life based on "new_board" values
  for ( int i = 0; i < width;i++) {
    for ( int j = 0; j < height;j++) {
        //stroke(color(new_board[(j*width)+i]));
        //stroke(255,0,0);
        //fill(255,0,0);
        //noStroke();
        pixels[j*width+i] = new_board[(j*width)+i];
        //point(i,j);
        //rect(i,j,10,10);
    }
  }
  updatePixels();
  //filter(BLUR,8);
  //swap old and new game of life boards
  int[] tmp = old_board;
  old_board = new_board;
  new_board = tmp;
    //updatePixels();
}

//init board with random "alive" squares
void initBoard() {
  
 // background(0);
// loadPixels();
       // old_board[2000] = color(255);
      old_board[((width*(height/2))+(width/2))] = color(255);
  //updatePixels();
}

//re-set board when mouse is pressed
void mousePressed() {
  initBoard();
}