game of life with 8x8 bicolor led matrix

I recently got one of those 8x8 LED matrices and I was playing with some Game of Life patterns when I found this pretty repeating pattern. I found it by starting with some random patterns. If you look closely you can see the pattern becoming a mirrored version of itself halfway through. Apparently the pattern doesn't repeat like this on an infinite grid but on this wrapping 8x8 grid it does ;-) FYI, the LED matrix is a bicolor one (green/red) and has an I2C interface (http://www.adafruit.com/products/902). I'm using the colors as follows: - newly created cells are green - cells that are at least 10 generations old are red - other living cells are yellow (simultaneously green+red) It's hookup up to my Arduino Uno r3. here's a video:Youtube

Code

/*

I recently got one of those 8x8 LED matrices  and I was playing with some Game of Life patterns when I found this pretty repeating pattern. I found it by starting with some random patterns. If you look closely you can see the pattern becoming a mirrored version of itself halfway through. Apparently the pattern doesn't repeat like this on an infinite grid but on this wrapping 8x8 grid it does ;-) 

 

FYI, the LED matrix is a bicolor one (green/red) and has an I2C interface (http://www.adafruit.com/products/902). I'm using the colors as follows:

 - newly created cells are green

 - cells that are at least 10 generations old are red

 - other living cells are yellow (simultaneously green+red)

 

It's hookup up to my Arduino Uno r3.

 

here's a video: http://www.youtube.com/watch?v=Ee2hOaQ2RDI

 

*/

 

#include 

#include "Adafruit_LEDBackpack.h"

#include "Adafruit_GFX.h"

 

boolean cells[8][8];

 

Adafruit_BicolorMatrix matrix = Adafruit_BicolorMatrix();

 

// game of life

int next[8][8];

 

void setup() {

  Serial.begin(9600);

  Serial.write("hello");

 

  randomSeed(analogRead(0));

  for (int r=0 ; r<8 r="" span="">

    for (int c=0 ; c<8 c="" span="">

      if (random(2) >0)

        next[r][c] = 1;

    }

 } 

 

  matrix.begin(0x70);  // pass in the address

}

 

void loop() {

 

  game_of_life();

}

 

int current[8][8] =

{ {0,0,0,0,0,0,0,0},

  {0,0,0,0,0,0,0,0},

  {0,0,1,1,1,0,0,0},

  {0,0,0,0,0,0,0,0},

  {0,0,0,0,0,0,0,0},

  {0,0,0,0,0,0,0,0},

  {0,0,0,0,0,0,0,0},

  {0,0,0,0,0,0,0,0} };

  

int mod(int a) { return (a+8)%8; }

 

void game_of_life() {

  

  matrix.clear();

  

  // draw

  for (int r=0 ; r<8 r="" span="">

    for (int c=0 ; c<8 c="" span="">

      int color;

      if (next[r][c] == 0)

        color = 0;

      else if (next[r][c] == 1) 

        color = LED_GREEN;

      else if (next[r][c] > 10)

        color = LED_RED;

      else

        color = LED_YELLOW;

      matrix.drawPixel(c,r,color);

    }

  }

  matrix.writeDisplay();

      

  // calc next state

  for (int r=0 ; r<8 r="" span="">

    for (int c=0 ; c<8 c="" span="">

      // count alive neighbors

      int alive = 0;

      alive += current[mod(r+1)][mod(c)  ] != 0;

      alive += current[mod(r)  ][mod(c+1)] != 0;

      alive += current[mod(r-1)][mod(c)  ] != 0;

      alive += current[mod(r)  ][mod(c-1)] != 0;

      alive += current[mod(r+1)][mod(c+1)] != 0;

      alive += current[mod(r-1)][mod(c-1)] != 0;

      alive += current[mod(r+1)][mod(c-1)] != 0;

      alive += current[mod(r-1)][mod(c+1)] != 0;

      if (current[r][c])

        if (alive < 2 || alive > 3)

          next[r][c] = 0;

        else

          next[r][c] = current[r][c] + 1;

      else

        if (alive == 3)

          next[r][c] = 1;

    }

  }    

  

  for (int r=0 ; r<8 r="" span="">

    for (int c=0 ; c<8 c="" span="">

      current[r][c] = next[r][c];

    }

  }  

  delay(100);

}