// <applet code="SF2DCA" width=500 height=300></applet>
// Snowflake fractal using 2D Cellular Automaton
// FB - 201007165
import java.applet.Applet;
import java.awt.*;
import java.awt.image.*;
public class SF2DCA extends Applet
{
Image img;
int w, h, pix[][], alpha, flag, ctr;
int dx[] = {2, 1, -1, -2, -1, 1};
int dy[] = {0, -1, -1, 0, 1, 1};
public void init()
{
setBackground ( Color.black );
w=getSize().width;
h=getSize().height;
alpha=255;
ctr = 0;
flag=1;
pix=new int[2][w * h];
putpixel(0, w / 2, h / 2, 255, 255, 255); // seed
}
public void putpixel(int flag, int x, int y, int red, int green, int blue)
{
pix[flag][w * y + x] = (alpha << 24) | (red << 16) | (green << 8) | blue;
}
public int getpixel(int flag, int x, int y)
{
return ((pix[flag][w * y + x] & 16777215) % 16777216);
}
public void paint(Graphics g)
{
if(ctr < 110) // grow until this size reached
{
flag = 1 - flag;
ctr++;
int sum, kx, ky;
for(int y = 0; y < h; y++)
for(int x = 0; x < w; x++)
if(getpixel(flag, x, y) == 0)
{
sum = 0; // count the neighbors
for(int j = 0; j < 6; j++)
{
kx = x + dx[j];
ky = y + dy[j];
if( kx >= 0 && kx < w && ky >= 0 && ky < h )
if(getpixel(flag, kx, ky) > 0)
sum++;
}
if(sum == 1) // add a new pixel only if there is 1 neighbor
putpixel(1 - flag, x, y, ctr % 8 * 32, ctr % 16 * 16, ctr % 32 * 8);
}
else
pix[1 - flag][w * y + x] = (alpha << 24) | getpixel(flag, x, y);
img = createImage(new MemoryImageSource(w, h, pix[1 - flag], 0, w));
g.drawImage(img, 0, 0, this);
repaint();
}
}
public void update(Graphics g) { paint(g); }
}
