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From 2012.igem.org

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Latest revision as of 18:02, 18 September 2012

// // atoms.js // // particle system- or physics-related datatypes //

var Node = function(data){ this._id = _nextNodeId++; // simple ints to allow the Kernel & ParticleSystem to chat this.data = data || {}; // the user-serviceable parts this._mass = (data.mass!==undefined) ? data.mass : 1 this._fixed = (data.fixed===true) ? true : false this._p = new Point((typeof(data.x)=='number') ? data.x : null,

                    (typeof(data.y)=='number') ? data.y : null)
 delete this.data.x
 delete this.data.y
 delete this.data.mass
 delete this.data.fixed

}; var _nextNodeId = 1

var Edge = function(source, target, data){ this._id = _nextEdgeId--; this.source = source; this.target = target; this.length = (data.length!==undefined) ? data.length : 1 this.data = (data!==undefined) ? data : {}; delete this.data.length }; var _nextEdgeId = -1

var Particle = function(position, mass){

 this.p = position;
 this.m = mass;

this.v = new Point(0, 0); // velocity this.f = new Point(0, 0); // force }; Particle.prototype.applyForce = function(force){ this.f = this.f.add(force.divide(this.m)); };

var Spring = function(point1, point2, length, k) { this.point1 = point1; // a particle this.point2 = point2; // another particle this.length = length; // spring length at rest this.k = k; // stiffness }; Spring.prototype.distanceToParticle = function(point) {

 // see http://stackoverflow.com/questions/849211/shortest-distance-between-a-point-and-a-line-segment/865080#865080
 var n = that.point2.p.subtract(that.point1.p).normalize().normal();
 var ac = point.p.subtract(that.point1.p);
 return Math.abs(ac.x * n.x + ac.y * n.y);

};

var Point = function(x, y){

 if (x && x.hasOwnProperty('y')){
   y = x.y; x=x.x;
 }
 this.x = x;
 this.y = y;  

}

Point.random = function(radius){

 radius = (radius!==undefined) ? radius : 5

return new Point(2*radius * (Math.random() - 0.5), 2*radius* (Math.random() - 0.5)); }

Point.prototype = {

 exploded:function(){
   return ( isNaN(this.x) || isNaN(this.y) )
 },
 add:function(v2){
 	return new Point(this.x + v2.x, this.y + v2.y);
 },
 subtract:function(v2){
 	return new Point(this.x - v2.x, this.y - v2.y);
 },
 multiply:function(n){
 	return new Point(this.x * n, this.y * n);
 },
 divide:function(n){
 	return new Point(this.x / n, this.y / n);
 },
 magnitude:function(){
 	return Math.sqrt(this.x*this.x + this.y*this.y);
 },
 normal:function(){
 	return new Point(-this.y, this.x);
 },
 normalize:function(){
 	return this.divide(this.magnitude());
 }

}