/**
 * Flade - Flash Dynamics Engine
 * Release 0.4 alpha 
 * Particle class
 * Copyright 2004, 2005 Alec Cove
 * 
 * This file is part of Flade. The Flash Dynamics Engine. 
 *	
 * Flade is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Flade is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Flade; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Flash is a registered trademark of Macromedia
 */
 
Particle = function(posX, posY) {

	// current and previous positions
	this.curr = new Vector(posX, posY);
	this.prev = new Vector(posX, posY);
	this.temp = new Vector(0,0);
	
	var drawClipName = "partdrawclip_" + this.depth;
	this.dmc = createEmptyMovieClip (drawClipName, this.depth);
	
	Particle.prototype.depth++;
}
Particle.prototype.depth = 1000;


Particle.prototype.verlet = function(sysObj) {
	this.temp.x = this.curr.x;
	this.temp.y = this.curr.y;

	this.curr.x += sysObj.coeffDamp * (this.curr.x - this.prev.x) + sysObj.gravity.x;
	this.curr.y += sysObj.coeffDamp * (this.curr.y - this.prev.y) + sysObj.gravity.y;

	this.prev.x = this.temp.x;
	this.prev.y = this.temp.y;
}


Particle.prototype.checkCollision = function(surface, sysObj) {
	surface.resolveParticleCollision(this, sysObj);
}


Particle.prototype.paint = function() {
	this.dmc.clear();
	this.dmc.lineStyle(0, 0x666666, 100);
	Graphics.prototype.paintCircle(this.dmc, this.curr.x, this.curr.y, 2);
}





Particle.prototype.setPos = function(px, py) {
	this.curr.x = px;
	this.curr.y = py;
	this.prev.x = px;
	this.prev.y = py;
}