/*
 * jQuery JavaScript Plugin jquery.starfieldTagCloud.js 0.9.1
 * http://bugsoftware.co.uk/jQuery/
 *
 * Copyright (c) 2010 Ritchie Comley
 * Dual licensed under the MIT and GPL licenses.
 *
 * Date: 2010-02-09 (Tue, 09 February 2010)
 * Revision: 36
 *
 * Dependencies:
 * jQuery 1.4 (jquery.com)
 * jQuery.engine3D.js (bugsoftware.co.uk)
 * jQuery.particlePhysics.js (bugsoftware.co.uk)
 * 
 */

(function(jQuery){ 

	jQuery.fn.starfieldTagCloud = function(options)
		{
			// PRIVATE VARIABLES		
			var defaults = {
					interval:50,             // interval between animation frames
					xPos: .5,                // x pos of where our tags 'fall' from
					yPos: .5,                // y pos of where our tags 'fall' from
					gravity: -10,            // force of gravity acting to drag items towards the screen - changing negive / positive changes direction of the 'fall'
					hoverGravityFactor:-1,   // gravity amount when user hovers over the tag cloud - works a multiplier of opts.gravity
					gravityVector:[0,0,1],   // 3D vector direction of gravity
					range:[-200,300]         // range to fall between - the lower the number the closer to the screen
				};
				
		 	var opts = jQuery.extend(defaults, options);
			
			var particles = [];
			var springs = [];
			
			var starField3D = function(scene, camera, width, height)
				{
					var i, p1, p2, dt = 0.1;

					var this3D = this;
					
					function renderParticles()
					{
						particles = jQuery.particlePhysics.updateParticles(particles, jQuery.particlePhysics.physical, springs, dt, 1);
						
						this3D.pointsArray.length = 0;
						
						for (i = 0; i < particles.length; i++)
						{
							// Display a particle at particles[i].p 
							
							// if out of z-range stick it back at the other end
							if(particles[i].p.z < opts.range[0])
							{
								randomize2DPos(particles[i], width, height);
								particles[i].p.z = opts.range[1];
							}
							
							if(particles[i].p.z > opts.range[1])
							{
								randomize2DPos(particles[i], width, height);
								particles[i].p.z = opts.range[0];
							}
							
							this3D.pointsArray.push(this3D.make3DPoint(particles[i].p.x, particles[i].p.y, particles[i].p.z));
						}
						
						scene.renderCamera(camera);
					}
					
					renderParticles();
					window.setInterval(renderParticles, opts.interval);
				};

			
				
			starField3D.prototype = new jQuery.engine3D.displayObject3D();
			
		 	return this.each(function() { 
			
					jQuery.particlePhysics.setGravityVector(opts.gravityVector[0], opts.gravityVector[1], opts.gravityVector[2]);
					
					jQuery.particlePhysics.setGravity(opts.gravity);
			
					var jCloud = jQuery(this);
					
					jCloud.mouseover(function()
						{
							jQuery.particlePhysics.setGravity(opts.gravity * opts.hoverGravityFactor);
						});
						
					jCloud.mouseout(function()
						{
							jQuery.particlePhysics.setGravity(opts.gravity);
						});
					
					var jCloudItems = jCloud.find('li');
					
					jCloud.css({
							overflow:'hidden',
							margin:0,
							padding:0,
							position:'relative'
						});
					
					jCloud.wrapInner('<div />');
					
					jCloud.find('ul').css({padding:0, margin:0, 'list-style':'none'});
					
					jCloud.find('>div').css({
							top:(opts.yPos*100)+'%',
							left:(opts.xPos*100)+'%',
							position:'relative',
							margin:0,
							padding:0,
							width:0,
							height:0,
							overflow:'visible'
						});

					jCloudItems.css({
							position:'relative',
							overflow:'visible',
							display:'block',
							margin:0,
							padding:0,
							position:'absolute'
						});
					
					jCloudItems.wrapInner('<div />');
					
					var jCloudItemDivs = jCloudItems.find('>div');
					
					
					
					jCloudItemDivs.css({
							'white-space':'nowrap',
							margin:0,
							padding:0
						});
					
					setupParticles(jCloudItems, jCloud.width(), jCloud.height(), opts.range);
					
					
					
					var scene = new jQuery.engine3D.scene3D();

					var camera = new jQuery.engine3D.camera3D();
					camera.init(0,0,0,300);
					
					var item = new jQuery.engine3D.object3D(jCloud);

					var starField3DObj = new starField3D(scene, camera, jCloud.width(), jCloud.height());
					
					item.addChild(starField3DObj);
					
					scene.addToScene(item);
					scene.renderCamera(camera);

				});
			
			function setupParticles(jParticles, xRange, yRange, zRange)
			{
				var i;
				
				particles = [];
				springs = [];

				jParticles.each(function(i)
					{
						particles[i] = {m:1, fixed:false, v:{x:0,y:0,z:0}, p:{}};
						
						randomize2DPos(particles[i], xRange, yRange);
						particles[i].p.z = ((zRange[1] - zRange[0])  * Math.random()) - ((zRange[0] + zRange[1]) / 2);
					});
			}
			
			function randomize2DPos(particle, xRange, yRange)
			{
				particle.p.x = (xRange * Math.random()) - (xRange / 2);
				particle.p.y = (yRange * Math.random()) - (yRange / 2);
			}
				
				
		};
		
})(jQuery);