// Fire applet by Anarchriz (c) 1998. All rights reserved. Contact me for more info.

import java.awt.*;
import java.applet.*;

public class FireApplet extends AnimatedApplet {
    private int[] pixelMap1;
    private int[] pixelMap2;
    private int[] temp;
    private int[] palette=new int[0x200];
    private int realWidth;
    private int realHeight;
    private int numberOfSources=25;
    private int widthSource=4;
    private int initHeat=0x100;
    private int blackDist=10;
    private boolean doubleSize=false;
    private boolean clipFire=true;
    
    private int heatWidth, position, convert;

    public void init(){
        super.init();
        
        String para1=getParameter("doubleSize");
        String para2=getParameter("clipFire");
        if (para1!=null) if (para1.equals("true")) doubleSize=true;
        if (para2!=null) if (para2.equals("false")) clipFire=false;
        
        if (doubleSize) {
            realWidth=width/2;
            realHeight=height/2;
            numberOfSources/=2;
            blackDist/=2;
            widthSource/=2;
        }
        else {
            realWidth=width;
            realHeight=height;
        }
        pixelMap1=new int[realWidth*(realHeight+blackDist)];
        pixelMap2=new int[realWidth*(realHeight+blackDist)];
        
        // Init pixel arrays to zero (black)
        for (int i=0; i<pixels.length; i++) pixels[i]=0;
        for (int i=0; i<pixelMap1.length; i++){
            pixelMap1[i]=0;
            pixelMap2[i]=0;
        }

        // Init the Palette
        for (int i=0; i<palette.length; i++) palette[i]=0;
        for (int i=0; i<0x10; i++){
            palette[i]=0;
        }
        for (int i=0x10; i<0x50; i++){
            palette[i]=((i-0x10)*4)<<16;
        }
        for (int i=0x30; i<0x70; i++){
            if (palette[i]!=0) palette[i]=palette[i]+(((i-0x30)*4)<<8);
            else palette[i]=0xFF0000+(((i-0x30)*4)<<8);
        }
        for (int i=0x70; i<0xB0; i++){
            palette[i]=0xFFFF00+((i-0x70)*4);
        }   
        
        setHotSpots();
    }
    
    public void setHotSpots(){
        // Set 'hot' points/lines
        for (int a=0; a<numberOfSources; a++){
            if (clipFire){
                heatWidth=realWidth-widthSource-8;
                position=6+(int)(heatWidth*Math.random());
            }
            else {
                heatWidth=realWidth-widthSource;
                position=(int)(heatWidth*Math.random());
            }
            for (int i=0; i<widthSource; i++){
                pixelMap1[(pixelMap1.length-realWidth-1)+i+position]=initHeat;
                pixelMap1[(pixelMap1.length-2*realWidth-1)+i+position]=initHeat;
            }
        }
    }
    
    public void loop(){
        temp=pixelMap1;

        for (int i=(pixelMap1.length-1-realWidth-1); i>=realWidth+1; i--){
            //For each pixel from pixelMap1 is the average of its environment calculated...
            int average=(pixelMap1[i-realWidth-1]+pixelMap1[i-realWidth]+pixelMap1[i-realWidth+1]+
                pixelMap1[i-1]+pixelMap1[i+1]+
                pixelMap1[i+realWidth-1]+pixelMap1[i+realWidth]+pixelMap1[i+realWidth+1])>>3;
            //... and put one line higher in pixelMap2 
            pixelMap2[i-realWidth]=average;

            //Convert heat numbers to 'real' colors in the pixels array
            if (i<realWidth*realHeight){
                if (!doubleSize){
                    if (average>=0xB0) pixels[i]=0xFFFFFF;
                    else pixels[i]=palette[average];
                }
                else {
                    convert=(i-i%realWidth)*4+(i%realWidth)*2;
                    if (average>=0xB0) {
                        pixels[convert]=0xFFFFFF;
                        pixels[convert+1]=0xFFFFFF;
                        pixels[convert+width]=0xFFFFFF;
                        pixels[convert+width+1]=0xFFFFFF;
                    }
                    else {
                        pixels[convert]=palette[average];
                        pixels[convert+1]=palette[average];
                        pixels[convert+width]=palette[average];
                        pixels[convert+width+1]=palette[average];
                    }
                }
            }
        }

        pixelMap1=pixelMap2;
        pixelMap2=temp;
        for (int i=0; i<pixelMap2.length; i++) pixelMap2[i]=0;

        setHotSpots();
	    
	    newPixels();
	    repaint();
    }
}