text: define("dojox/gfx3d/lighting", [
  	"dojo/_base/lang",
  	"dojo/_base/Color",	// dojo.Color
  	"dojo/_base/declare",	// declare
  	"dojox/gfx/_base",
  	"./_base"
  ],function(lang,Color,declare,gfx,gfx3d) {
  
  	var lite = gfx3d.lighting = {
  		// color utilities
  		black: function(){
  			return {r: 0, g: 0, b: 0, a: 1};
  		},
  		white: function(){
  			return {r: 1, g: 1, b: 1, a: 1};
  		},
  		toStdColor: function(c){
  			c = gfx.normalizeColor(c);
  			return {r: c.r / 255, g: c.g / 255, b: c.b / 255, a: c.a};
  		},
  		fromStdColor: function(c){
  			return new Color([Math.round(255 * c.r), Math.round(255 * c.g), Math.round(255 * c.b), c.a]);
  		},
  		scaleColor: function(s, c){
  			return {r: s * c.r, g: s * c.g, b: s * c.b, a: s * c.a};
  		},
  		addColor: function(a, b){
  			return {r: a.r + b.r, g: a.g + b.g, b: a.b + b.b, a: a.a + b.a};
  		},
  		multiplyColor: function(a, b){
  			return {r: a.r * b.r, g: a.g * b.g, b: a.b * b.b, a: a.a * b.a};
  		},
  		saturateColor: function(c){
  			return {
  				r: c.r < 0 ? 0 : c.r > 1 ? 1 : c.r,
  				g: c.g < 0 ? 0 : c.g > 1 ? 1 : c.g,
  				b: c.b < 0 ? 0 : c.b > 1 ? 1 : c.b,
  				a: c.a < 0 ? 0 : c.a > 1 ? 1 : c.a
  			};
  		},
  		mixColor: function(c1, c2, s){
  			return lite.addColor(lite.scaleColor(s, c1), lite.scaleColor(1 - s, c2));
  		},
  		diff2Color: function(c1, c2){
  			var r = c1.r - c2.r;
  			var g = c1.g - c2.g;
  			var b = c1.b - c2.b;
  			var a = c1.a - c2.a;
  			return r * r + g * g + b * b + a * a;
  		},
  		length2Color: function(c){
  			return c.r * c.r + c.g * c.g + c.b * c.b + c.a * c.a;
  		},
  		
  		// vector utilities
  		//TODO: move vector utilities from this file to vector.js
  		dot: function(a, b){
  			return a.x * b.x + a.y * b.y + a.z * b.z;
  		},
  		scale: function(s, v){
  			return {x: s * v.x, y: s * v.y, z: s * v.z};
  		},
  		add: function(a, b){
  			return {x: a.x + b.x, y: a.y + b.y, z: a.z + b.z};
  		},
  		saturate: function(v){
  			return Math.min(Math.max(v, 0), 1);
  		},
  		length: function(v){
  			return Math.sqrt(gfx3d.lighting.dot(v, v));
  		},
  		normalize: function(v){
  			return lite.scale(1 / lite.length(v), v);
  		},
  		faceforward: function(n, i){
  			var p = gfx3d.lighting;
  			var s = p.dot(i, n) < 0 ? 1 : -1;
  			return p.scale(s, n);
  		},
  		reflect: function(i, n){
  			var p = gfx3d.lighting;
  			return p.add(i, p.scale(-2 * p.dot(i, n), n));
  		},
  		
  		// lighting utilities
  		diffuse: function(normal, lights){
  			var c = lite.black();
  			for(var i = 0; i < lights.length; ++i){
  				var l = lights[i],
  					d = lite.dot(lite.normalize(l.direction), normal);
  				c = lite.addColor(c, lite.scaleColor(d, l.color));
  			}
  			return lite.saturateColor(c);
  		},
  		specular: function(normal, v, roughness, lights){
  			var c = lite.black();
  			for(var i = 0; i < lights.length; ++i){
  				var l = lights[i],
  					h = lite.normalize(lite.add(lite.normalize(l.direction), v)),
  					s = Math.pow(Math.max(0, lite.dot(normal, h)), 1 / roughness);
  				c = lite.addColor(c, lite.scaleColor(s, l.color));
  			}
  			return lite.saturateColor(c);
  		},
  		phong: function(normal, v, size, lights){
  			normal = lite.normalize(normal);
  			var c = lite.black();
  			for(var i = 0; i < lights.length; ++i){
  				var l = lights[i],
  					r = lite.reflect(lite.scale(-1, lite.normalize(v)), normal),
  					s = Math.pow(Math.max(0, lite.dot(r, lite.normalize(l.direction))), size);
  				c = lite.addColor(c, lite.scaleColor(s, l.color));
  			}
  			return lite.saturateColor(c);
  		}
  	};
  
  	// this lighting model is derived from RenderMan Interface Specification Version 3.2
  
  	declare("dojox.gfx3d.lighting.Model", null, {
  		constructor: function(incident, lights, ambient, specular){
  			this.incident = lite.normalize(incident);
  			this.lights = [];
  			for(var i = 0; i < lights.length; ++i){
  				var l = lights[i];
  				this.lights.push({direction: lite.normalize(l.direction), color: lite.toStdColor(l.color)});
  			}
  			this.ambient = lite.toStdColor(ambient.color ? ambient.color : "white");
  			this.ambient = lite.scaleColor(ambient.intensity, this.ambient);
  			this.ambient = lite.scaleColor(this.ambient.a, this.ambient);
  			this.ambient.a = 1;
  			this.specular = lite.toStdColor(specular ? specular : "white");
  			this.specular = lite.scaleColor(this.specular.a, this.specular);
  			this.specular.a = 1;
  			this.npr_cool = {r: 0,   g: 0,   b: 0.4, a: 1};
  			this.npr_warm = {r: 0.4, g: 0.4, b: 0.2, a: 1};
  			this.npr_alpha = 0.2;
  			this.npr_beta  = 0.6;
  			this.npr_scale = 0.6;
  		},
  		constant: function(normal, finish, pigment){
  			pigment   = lite.toStdColor(pigment);
  			var alpha = pigment.a, color = lite.scaleColor(alpha, pigment);
  			color.a   = alpha;
  			return lite.fromStdColor(lite.saturateColor(color));
  		},
  		matte: function(normal, finish, pigment){
  			if(typeof finish == "string"){ finish = lite.finish[finish]; }
  			pigment = lite.toStdColor(pigment);
  			normal  = lite.faceforward(lite.normalize(normal), this.incident);
  			var ambient = lite.scaleColor(finish.Ka, this.ambient),
  				shadow  = lite.saturate(-4 * lite.dot(normal, this.incident)),
  				diffuse = lite.scaleColor(shadow * finish.Kd, lite.diffuse(normal, this.lights)),
  				color   = lite.scaleColor(pigment.a, lite.multiplyColor(pigment, lite.addColor(ambient, diffuse)));
  			color.a = pigment.a;
  			return lite.fromStdColor(lite.saturateColor(color));
  		},
  		metal: function(normal, finish, pigment){
  			if(typeof finish == "string"){ finish = lite.finish[finish]; }
  			pigment = lite.toStdColor(pigment);
  			normal  = lite.faceforward(lite.normalize(normal), this.incident);
  			var v = lite.scale(-1, this.incident), specular, color,
  				ambient = lite.scaleColor(finish.Ka, this.ambient),
  				shadow  = lite.saturate(-4 * lite.dot(normal, this.incident));
  			if("phong" in finish){
  				specular = lite.scaleColor(shadow * finish.Ks * finish.phong, lite.phong(normal, v, finish.phong_size, this.lights));
  			}else{
  				specular = lite.scaleColor(shadow * finish.Ks, lite.specular(normal, v, finish.roughness, this.lights));
  			}
  			color = lite.scaleColor(pigment.a, lite.addColor(lite.multiplyColor(pigment, ambient), lite.multiplyColor(this.specular, specular)));
  			color.a = pigment.a;
  			return lite.fromStdColor(lite.saturateColor(color));
  		},
  		plastic: function(normal, finish, pigment){
  			if(typeof finish == "string"){ finish = lite.finish[finish]; }
  			pigment = lite.toStdColor(pigment);
  			normal  = lite.faceforward(lite.normalize(normal), this.incident);
  			var v = lite.scale(-1, this.incident), specular, color,
  				ambient = lite.scaleColor(finish.Ka, this.ambient),
  				shadow  = lite.saturate(-4 * lite.dot(normal, this.incident)),
  				diffuse = lite.scaleColor(shadow * finish.Kd, lite.diffuse(normal, this.lights));
  			if("phong" in finish){
  				specular = lite.scaleColor(shadow * finish.Ks * finish.phong, lite.phong(normal, v, finish.phong_size, this.lights));
  			}else{
  				specular = lite.scaleColor(shadow * finish.Ks, lite.specular(normal, v, finish.roughness, this.lights));
  			}
  			color = lite.scaleColor(pigment.a, lite.addColor(lite.multiplyColor(pigment, lite.addColor(ambient, diffuse)), lite.multiplyColor(this.specular, specular)));
  			color.a = pigment.a;
  			return lite.fromStdColor(lite.saturateColor(color));
  		},
  		npr: function(normal, finish, pigment){
  			if(typeof finish == "string"){ finish = lite.finish[finish]; }
  			pigment = lite.toStdColor(pigment);
  			normal  = lite.faceforward(lite.normalize(normal), this.incident);
  			var ambient  = lite.scaleColor(finish.Ka, this.ambient),
  				shadow   = lite.saturate(-4 * lite.dot(normal, this.incident)),
  				diffuse  = lite.scaleColor(shadow * finish.Kd, lite.diffuse(normal, this.lights)),
  				color = lite.scaleColor(pigment.a, lite.multiplyColor(pigment, lite.addColor(ambient, diffuse))),
  				cool = lite.addColor(this.npr_cool, lite.scaleColor(this.npr_alpha, color)),
  				warm = lite.addColor(this.npr_warm, lite.scaleColor(this.npr_beta,  color)),
  				d = (1 + lite.dot(this.incident, normal)) / 2,
  				color = lite.scaleColor(this.npr_scale, lite.addColor(color, lite.mixColor(cool, warm, d)));
  			color.a = pigment.a;
  			return lite.fromStdColor(lite.saturateColor(color));
  		}
  	});
  
  
  	// POV-Ray basic finishes
  	
  	gfx3d.lighting.finish = {
  	
  		// Default
  		
  		defaults: {Ka: 0.1, Kd: 0.6, Ks: 0.0, roughness: 0.05},
  		
  		dull:     {Ka: 0.1, Kd: 0.6, Ks: 0.5, roughness: 0.15},
  		shiny:    {Ka: 0.1, Kd: 0.6, Ks: 1.0, roughness: 0.001},
  		glossy:   {Ka: 0.1, Kd: 0.6, Ks: 1.0, roughness: 0.0001},
  		
  		phong_dull:   {Ka: 0.1, Kd: 0.6, Ks: 0.5, phong: 0.5, phong_size: 1},
  		phong_shiny:  {Ka: 0.1, Kd: 0.6, Ks: 1.0, phong: 1.0, phong_size: 200},
  		phong_glossy: {Ka: 0.1, Kd: 0.6, Ks: 1.0, phong: 1.0, phong_size: 300},
  	
  		luminous: {Ka: 1.0, Kd: 0.0, Ks: 0.0, roughness: 0.05},
  	
  		// Metals
  	
  		// very soft and dull
  		metalA: {Ka: 0.35, Kd: 0.3, Ks: 0.8, roughness: 1/20},
  		// fairly soft and dull
  		metalB: {Ka: 0.30, Kd: 0.4, Ks: 0.7, roughness: 1/60},
  		// medium reflectivity, holds color well
  		metalC: {Ka: 0.25, Kd: 0.5, Ks: 0.8, roughness: 1/80},
  		// highly hard and polished, high reflectivity
  		metalD: {Ka: 0.15, Kd: 0.6, Ks: 0.8, roughness: 1/100},
  		// very highly polished and reflective
  		metalE: {Ka: 0.10, Kd: 0.7, Ks: 0.8, roughness: 1/120}
  	};
  
  	return lite;
  });
  