Cellular automata in Processing

I am experimenting with cellular automata behaviours in Processing…computation took some time so this is just a quick time-lapse recording made with my iPhone rather than exporting single frames and converting them to hight quality video.

 

Cell[][] _cellArray;

int _cellSize = 2;
int _numX, _numY;

void setup()
{
  size(256, 256);
  _numX = floor(width/_cellSize);
  _numY = floor(height/_cellSize);

  frameRate(60);
  strokeWeight(0);

  restart();
}

void restart()
{
  _cellArray = new Cell[_numX][_numY];

  for (int x = 0; x < _numX; x++)
  {
    for (int y = 0; y < _numY; y++)
    {
      Cell newCell = new Cell(x, y);
      _cellArray[x][y] = newCell;
    }
  }

  for (int x = 0; x < _numX; x++)
  {
    for (int y = 0; y < _numY; y++)
    {
      int above = y-1;
      int below = y+1;
      int left = x-1;
      int right = x+1;

      if (above < 0) above = _numY-1;
      if (below == _numY) below = 0;
      if (left < 0) left = _numX-1;
      if (right == _numX) right = 0;

      _cellArray[x][y].addNeighbor(_cellArray[left][above]);
      _cellArray[x][y].addNeighbor(_cellArray[left][y]);
      _cellArray[x][y].addNeighbor(_cellArray[left][below]);

      _cellArray[x][y].addNeighbor(_cellArray[x][above]);
      _cellArray[x][y].addNeighbor(_cellArray[x][below]);

      _cellArray[x][y].addNeighbor(_cellArray[right][above]);
      _cellArray[x][y].addNeighbor(_cellArray[right][y]);
      _cellArray[x][y].addNeighbor(_cellArray[right][below]);
    }
  }
}


void draw()
{
  //if (millis() % 5 == 0)
  //  restart();

  background(200);

  for (int x = 0; x < _numX; x++)
  {
    for (int y = 0; y < _numY; y++)
    {
      _cellArray[x][y].calcNextState();
    }
  }

  translate(_cellSize/2, _cellSize/2);
  for (int x = 0; x < _numX; x++)
  {
    for (int y = 0; y < _numY; y++)
    {
      _cellArray[x][y].drawMe();
    }
  }
}


////////////////////////////////////////////////////////////////////////////////////////////////////////////

class Cell {
  float x, y;
  float state;
  float nextState;
  float lastState = 0;

  Cell[] neighbors;

  Cell(float ex, float why)
  {
    x = ex * _cellSize;
    y = why * _cellSize;

    nextState = ((x/500) + (y/300)) * 14;

    state = nextState;
    neighbors = new Cell[0];
  }

  void addNeighbor(Cell cell)
  {
    neighbors = (Cell[])append(neighbors, cell);
  }

  void calcNextState()
  {
    float total = 0;
    for (int i = 0; i < neighbors.length; i++)
      total += neighbors[i].state;

    float average = int(total/8);

    if (average == 255)
      nextState = 0;
    else if (average == 0)
      nextState = 255;
    else 
    {
      nextState = state + average;

      if (lastState > 0)
        nextState -= lastState;
      if (nextState > 255)
        nextState = 255;
      else if (nextState < 0)
        nextState = 0;
    }

    lastState = state;
  }

  void drawMe()
  {
    state = nextState;

    fill(state);

    rect(x,y,_cellSize, _cellSize);
  }

}

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