/**
 * Flade - Flash Dynamics Engine
 * Release 0.4 alpha 
 * Constraint 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
 */
 
 
Constraint = function(p1, p2) {
	
	this.p1 = p1;
	this.p2 = p2;
	this.restLength = p1.curr.distance(p2.curr);

	var drawClipName = "constdrawclip_" + this.depth;
	this.dmc = createEmptyMovieClip (drawClipName, this.depth);
	
	
	Constraint.prototype.depth++;
}
Constraint.prototype.depth = 3000;


Constraint.prototype.resolve = function() {
		
	var delta = this.p1.curr.minusNew(this.p2.curr);
	var deltaLength = this.p1.curr.distance(this.p2.curr);
	
	var diff = (deltaLength - this.restLength) / deltaLength;
	var dmd = delta.mult(diff * 0.5);
			
	this.p1.curr.minus(dmd);
	this.p2.curr.plus(dmd);
}


Constraint.prototype.setRestLength = function(r) {
	this.restLength = r;
}


Constraint.prototype.paint = function() {
	
	this.dmc.clear();
	this.dmc.lineStyle(0, 0x996633, 100);
	
	Graphics.prototype.paintLine(
			this.dmc, 
			this.p1.curr.x, 
			this.p1.curr.y, 
			this.p2.curr.x, 
			this.p2.curr.y);
	
}