// <applet code="Plasma" width=800 height=600></applet>
// FB - 201003265
// Color-Cycling Plasma Fractal
import java.applet.Applet;
import java.awt.*;
import java.awt.image.*;
public class Plasma extends Applet
{
Image img;
// pix will hold the actual image data
// mat will hold the image data of palette colors
int pix[], mat[];
int red[],green[],blue[];
int w,h,inc;
float roughness;
long ctm;
public void adjust(int xa,int ya,int x,int y,int xb,int yb)
{
int c,d;
if(mat[w*y+x]==0)
{
d=(int)(Math.abs(xa-xb)+Math.abs(ya-yb));
c=(mat[w*ya+xa]+mat[w*yb+xb])/2+(int)((Math.random()-0.5)*d*roughness);
c=((int)Math.abs(c))%256;
mat[w*y+x]=c;
}
}
public void subdivide(int x1,int y1,int x2,int y2)
{
int x,y;
if(!((x2-x1<2) && (y2-y1<2)))
{
x=(x1+x2)/2;y=(y1+y2)/2;
adjust(x1,y1,x,y1,x2,y1);adjust(x2,y1,x2,y,x2,y2);
adjust(x1,y2,x,y2,x2,y2);adjust(x1,y1,x1,y,x1,y2);
if(mat[w*y+x]==0)
{
mat[w*y+x]=(mat[w*y1+x1]+mat[w*y1+x2]+mat[w*y2+x2]+mat[w*y2+x1])/4;
}
subdivide(x1,y1,x,y);subdivide(x,y1,x2,y);
subdivide(x,y,x2,y2);subdivide(x1,y,x,y2);
}
}
public void init()
{
// create a color palette (RGBY)
red=new int[256];green=new int[256];blue=new int[256];
for(int i=0;i<256;i++)
{
switch((int)(i/64))
{
case 0:
red[i]=(i%64)*3+64;
green[i]=0;
blue[i]=0;
break;
case 1:
red[i]=0;
green[i]=(i%64)*3+64;
blue[i]=0;
break;
case 2:
red[i]=0;
green[i]=0;
blue[i]=(i%64)*3+64;
break;
case 3:
red[i]=(i%64)*3+64;
green[i]=(i%64)*3+64;
blue[i]=0;
break;
}
}
ctm=System.currentTimeMillis();
inc=(int)(Math.random()*7+1)*((int)(Math.random()*2)*2-1);
roughness=(float)Math.random()*6+1;
w=getSize().width;h=getSize().height;
pix=new int[w*h]; mat=new int[w*h];
// put random color pixels to the 4 corners
for(int y=0;y<2;y++)
for(int x=0;x<2;x++)
mat[w*y*(h-1)+x*(w-1)]=(int)(Math.random()*256);
subdivide(0,0,w-1,h-1);
}
public void paint(Graphics g)
{
int c;
int alpha=255;
// restart the applet periodically
if((System.currentTimeMillis()-ctm)>=10000) init();
// keep the color-cycling speed constant between different PCs!
long t=System.currentTimeMillis();
while((System.currentTimeMillis()-t)<10) {;}
// rotate the colors (the palette)
for(int y=0;y<h;y++)
for(int x=0;x<w;x++)
{
mat[w*y+x]=(mat[w*y+x]+inc+256)%256; c=mat[w*y+x];
// convert image data of palette colors to actual image data
pix[w*y+x]=(alpha<<24)|(red[c]<<16)|(green[c]<<8)|blue[c];
}
img=createImage(new MemoryImageSource(w,h,pix,0,w));
g.drawImage(img,0,0,this);
repaint();
}
public void update(Graphics g) { paint(g); } // no flickering!
}
