// Fw3D.java
// Flower Works Fire Ball Class
// Copyright (C) 1997,1998 Yukinori NAGATANI
// nagatani@eken.phys.nagoya-u.ac.jp

import java.awt.Color;

public class  Fw3D {
	public Fw3D	next;
	
	public double	x,	y,	z;	// position
	public double	xV,	yV,	zV;	// velocity
	public double	rFriction;
	public int	nLifeTime,	nTime;
	public int	nGeneration;
	public Color	colorFirst,	colorMid,	colorFinal;
	
	public void reset () {
		next = null;
		x = y = z = 0.0;
		xV = yV = zV = 0.0;
		rFriction = 0.0;
		nLifeTime = nTime = 0;
		nGeneration = 0;
		colorFirst = colorMid = colorFinal = Color.white;
	}
	Fw3D () {		// default constructor
		reset ();
	}			// constructor
	Fw3D (double x, double y, double z, double xV, double yV, double zV,
	    double rFriction, int nLifeTime, int nGeneration) {
		reset ();
		this.x		  = x;
		this.y	 	  = y;
		this.z	 	  = z;
		this.xV		  = xV;
		this.yV		  = yV;
		this.zV		  = zV;
		this.rFriction	  = rFriction;
		this.nLifeTime	  = this.nTime = nLifeTime;
		this.nGeneration = nGeneration;
	}
	Fw3D (Fw3D fw)	// copy constructor
	{
		reset ();
		this.x  	 = fw.x;
		this.y  	 = fw.y;
		this.z  	 = fw.z;
		this.xV 	 = fw.xV;
		this.yV		 = fw.yV;
		this.zV		 = fw.zV;
		this.rFriction	 = fw.rFriction;
		this.nLifeTime	 = fw.nLifeTime;
		this.nTime	 = fw.nTime;
		this.nGeneration = fw.nGeneration;
		this.colorFirst	 = fw.colorFirst;
		this.colorMid	 = fw.colorMid;
		this.colorFinal	 = fw.colorFinal;
	}
	public void evolute () {
		x += xV;
		y += yV;
		z += zV;
		xV += +0.00 - rFriction*xV;
		yV += +0.00 - rFriction*yV;
		zV += -0.15 - rFriction*zV;
		nTime--;
	}
	public Color getColor () {
		if (nTime < 5)
			return	colorFinal;
		if (nLifeTime - nTime < 4 + (int)(4.0*Math.random()))
			return	colorFirst;
		return	colorMid;
	}
};