class Grid {

  int w = 8;
  int columns, rows;
  int water = 60;
  float c;
  float[][] room;
  Square[] boxes = {
    //x, y,(where) w, h, (size). Append because "box" only contains 3 variables, need 4.
     new Square(0,1,5,80),
     new Square(25,64,8,4),
     new Square(5,1,4,17),
     new Square(25,68,21,13),
     new Square(9,1,12,12),
     new Square(5,55,3,26),
     new Square(21,1,5,8),
     new Square(27,62,3,2),
     new Square(39,1,42,28),
     new Square(26,56,2,6),
     new Square(44,12,37,28),
     new Square(27,54,2,2),
     new Square(36,15,3,13),
     new Square(26,1,3,3),
     new Square(71,1,10,80),
     new Square(42,36,3,4),
     new Square(68,54,3,7),
     new Square(46,78,25,3),
     new Square(65,64,6,5),
     new Square(68,69,3,4),
     new Square(64,73,7,5),
     new Square(51,70,4,2),
     new Square(35,37,3,3),
     new Square(46,63,10,7),
     new Square(35,40,18,7),
     new Square(43,59,3,9),
     new Square(53,40,6,4),
     new Square(41,53,7,6),
     new Square(32,47,14,6),
     new Square(29,51,3,3)
  };

  Grid() {
    columns = width/w;
    rows = height/w;
    room = new float[columns][rows];
    init();
  }
  //this maps out the placement of watercells
  void init() {
    for (int i =0; i < columns; i++) {
      for (int j =0; j < rows; j++) {
      room[i][j] = 0;
      }
    }
  }

  void initBoundary() {
    for (int i =0; i < columns; i++) {
      room[i][0]=1.0;
    }

    for (int i = 0; i < boxes.length; i++) {
      for (int j =boxes[i].x; j < boxes[i].w+boxes[i].x; j++) {
        for (int k =boxes[i].y; k < boxes[i].h+boxes[i].y; k++){
            room[j][k] = 1;
        }
      }
    }
  }

  void generate() {
    float[][] next = new float[columns][rows];
    for (int x = 1; x < columns-1; x++) {
      for (int y = 1; y < rows-1; y++) {
        float neighbors = 0;
        for (int i = -1; i <= 1; i++) {
          for (int j = -1; j <= 1; j++) {
            neighbors += room[x+i][y+j];
            next[x][y] = neighbors/9.0;
          }
        }
      }
    }
    room = next;
    initBoundary();
  }

  void display() {
    for ( int i = 0; i < columns; i++) {
    for ( int j = 0; j < rows; j++) {
    c = map(room[i][j],0, 2, 0, 255); //sets the color of cells from their values
    fill(0 , water, c);
    rect(i*w, j*w, w, w);
    }
  }
  }
}