/**
 * @author supereggbert / http://www.paulbrunt.co.uk/
 * @author mrdoob / http://mrdoob.com/
 * @author alteredq / http://alteredqualia.com/
 * @author szimek / https://github.com/szimek/
 */

THREE.WebGLRenderer = function ( parameters ) {

	// Currently you can use just up to 4 directional / point lights total.
	// Chrome barfs on shader linking when there are more than 4 lights :(

	// The problem comes from shader using too many varying vectors.

	// This is not GPU limitation as the same shader works ok in Firefox
	// and Chrome with "--use-gl=desktop" flag.

	// Difference comes from Chrome on Windows using by default ANGLE,
	// thus going DirectX9 route (while FF uses OpenGL).

	// See http://code.google.com/p/chromium/issues/detail?id=63491

	var _this = this,
	_gl, _programs = [],
	_currentProgram = null,
	_currentFramebuffer = null,
	_currentDepthMask = true,

	// gl state cache

	_oldDoubleSided = null,
	_oldFlipSided = null,
	_oldBlending = null,
	_oldDepth = null,
	_oldPolygonOffset = null,
	_oldPolygonOffsetFactor = null,
	_oldPolygonOffsetUnits = null,
	_cullEnabled = true,

	_viewportX = 0,
	_viewportY = 0,
	_viewportWidth = 0,
	_viewportHeight = 0,

	// camera matrices caches

	_frustum = [
		new THREE.Vector4(),
		new THREE.Vector4(),
		new THREE.Vector4(),
		new THREE.Vector4(),
		new THREE.Vector4(),
		new THREE.Vector4()
	 ],

	_projScreenMatrix = new THREE.Matrix4(),
	_projectionMatrixArray = new Float32Array( 16 ),
	_viewMatrixArray = new Float32Array( 16 ),

	_vector3 = new THREE.Vector4(),

	// light arrays cache

	_lights = {

		ambient: [ 0, 0, 0 ],
		directional: { length: 0, colors: new Array(), positions: new Array() },
		point: { length: 0, colors: new Array(), positions: new Array(), distances: new Array() }

	},

	// parameters

	parameters = parameters || {},

	_canvas = parameters.canvas !== undefined ? parameters.canvas : document.createElement( 'canvas' ),
	_stencil = parameters.stencil !== undefined ? parameters.stencil : true,
	_preserveDrawingBuffer = parameters.preserveDrawingBuffer !== undefined ? parameters.preserveDrawingBuffer : false,
	_antialias = parameters.antialias !== undefined ? parameters.antialias : false,
	_clearColor = parameters.clearColor !== undefined ? new THREE.Color( parameters.clearColor ) : new THREE.Color( 0x000000 ),
	_clearAlpha = parameters.clearAlpha !== undefined ? parameters.clearAlpha : 0;

	this.data = {

		vertices: 0,
		faces: 0,
		drawCalls: 0

	};

	this.maxMorphTargets = 8;
	this.domElement = _canvas;
	this.autoClear = true;
	this.sortObjects = true;

	// shadow map

	this.shadowMapBias = 0.0039;
	this.shadowMapDarkness = 0.5;
	this.shadowMapWidth = 512;
	this.shadowMapHeight = 512;

	this.shadowCameraNear = 1;
	this.shadowCameraFar = 5000;
	this.shadowCameraFov = 50;

	this.shadowMap = [];
	this.shadowMapEnabled = false;
	this.shadowMapSoft = true;

	var _cameraLight, _shadowMatrix = [];

	var depthShader = THREE.ShaderLib[ "depthRGBA" ];
	var depthUniforms = THREE.UniformsUtils.clone( depthShader.uniforms );

	var _depthMaterial = new THREE.MeshShaderMaterial( { fragmentShader: depthShader.fragmentShader, vertexShader: depthShader.vertexShader, uniforms: depthUniforms } );

	var _depthMaterialMorph = new THREE.MeshShaderMaterial( { fragmentShader: depthShader.fragmentShader, vertexShader: depthShader.vertexShader, uniforms: depthUniforms, morphTargets: true } );

	_depthMaterial._shadowPass = true;
	_depthMaterialMorph._shadowPass = true;

	// Init GL

	try {

		if ( ! ( _gl = _canvas.getContext( 'experimental-webgl', { antialias: _antialias, stencil: _stencil, preserveDrawingBuffer: _preserveDrawingBuffer } ) ) ) {

			throw 'Error creating WebGL context.';

		}

		console.log(
			navigator.userAgent + " | " +
			_gl.getParameter( _gl.VERSION ) + " | " +
			_gl.getParameter( _gl.VENDOR ) + " | " +
			_gl.getParameter( _gl.RENDERER ) + " | " +
			_gl.getParameter( _gl.SHADING_LANGUAGE_VERSION )
		);

	} catch ( error ) {

		console.error( error );

	}

	_gl.clearColor( 0, 0, 0, 1 );
	_gl.clearDepth( 1 );

	_gl.enable( _gl.DEPTH_TEST );
	_gl.depthFunc( _gl.LEQUAL );

	_gl.frontFace( _gl.CCW );
	_gl.cullFace( _gl.BACK );
	_gl.enable( _gl.CULL_FACE );

	_gl.enable( _gl.BLEND );
	_gl.blendEquation( _gl.FUNC_ADD );
	_gl.blendFunc( _gl.SRC_ALPHA, _gl.ONE_MINUS_SRC_ALPHA );

	_gl.clearColor( _clearColor.r, _clearColor.g, _clearColor.b, _clearAlpha );

	_cullEnabled = true;

	//

	this.context = _gl;

	var _supportsVertexTextures = ( maxVertexTextures() > 0 );

	// prepare sprites

	var _sprite = {};

	_sprite.vertices = new Float32Array( 8 + 8 );
	_sprite.faces    = new Uint16Array( 6 );

	i = 0;

	_sprite.vertices[ i++ ] = -1; _sprite.vertices[ i++ ] = -1;	// vertex 0
	_sprite.vertices[ i++ ] = 0;  _sprite.vertices[ i++ ] = 1;	// uv 0

	_sprite.vertices[ i++ ] = 1;  _sprite.vertices[ i++ ] = -1;	// vertex 1
	_sprite.vertices[ i++ ] = 1;  _sprite.vertices[ i++ ] = 1;	// uv 1

	_sprite.vertices[ i++ ] = 1;  _sprite.vertices[ i++ ] = 1;	// vertex 2
	_sprite.vertices[ i++ ] = 1;  _sprite.vertices[ i++ ] = 0;	// uv 2

	_sprite.vertices[ i++ ] = -1; _sprite.vertices[ i++ ] = 1;	// vertex 3
	_sprite.vertices[ i++ ] = 0;  _sprite.vertices[ i++ ] = 0;	// uv 3

	i = 0;
	_sprite.faces[ i++ ] = 0; _sprite.faces[ i++ ] = 1; _sprite.faces[ i++ ] = 2;
	_sprite.faces[ i++ ] = 0; _sprite.faces[ i++ ] = 2; _sprite.faces[ i++ ] = 3;

	_sprite.vertexBuffer  = _gl.createBuffer();
	_sprite.elementBuffer = _gl.createBuffer();

	_gl.bindBuffer( _gl.ARRAY_BUFFER, _sprite.vertexBuffer );
	_gl.bufferData( _gl.ARRAY_BUFFER,  _sprite.vertices, _gl.STATIC_DRAW );

	_gl.bindBuffer( _gl.ELEMENT_ARRAY_BUFFER, _sprite.elementBuffer );
	_gl.bufferData( _gl.ELEMENT_ARRAY_BUFFER, _sprite.faces, _gl.STATIC_DRAW );


	_sprite.program = _gl.createProgram();
	_gl.attachShader( _sprite.program, getShader( "fragment", THREE.ShaderLib.sprite.fragmentShader ));
	_gl.attachShader( _sprite.program, getShader( "vertex",   THREE.ShaderLib.sprite.vertexShader   ));
	_gl.linkProgram( _sprite.program );

	_sprite.attributes = {};
	_sprite.uniforms = {};
	_sprite.attributes.position           = _gl.getAttribLocation ( _sprite.program, "position" );
	_sprite.attributes.uv                 = _gl.getAttribLocation ( _sprite.program, "uv" );
	_sprite.uniforms.uvOffset             = _gl.getUniformLocation( _sprite.program, "uvOffset" );
	_sprite.uniforms.uvScale              = _gl.getUniformLocation( _sprite.program, "uvScale" );
	_sprite.uniforms.rotation             = _gl.getUniformLocation( _sprite.program, "rotation" );
	_sprite.uniforms.scale                = _gl.getUniformLocation( _sprite.program, "scale" );
	_sprite.uniforms.alignment            = _gl.getUniformLocation( _sprite.program, "alignment" );
	_sprite.uniforms.map                  = _gl.getUniformLocation( _sprite.program, "map" );
	_sprite.uniforms.opacity              = _gl.getUniformLocation( _sprite.program, "opacity" );
	_sprite.uniforms.useScreenCoordinates = _gl.getUniformLocation( _sprite.program, "useScreenCoordinates" );
	_sprite.uniforms.affectedByDistance   = _gl.getUniformLocation( _sprite.program, "affectedByDistance" );
	_sprite.uniforms.screenPosition    	  = _gl.getUniformLocation( _sprite.program, "screenPosition" );
	_sprite.uniforms.modelViewMatrix      = _gl.getUniformLocation( _sprite.program, "modelViewMatrix" );
	_sprite.uniforms.projectionMatrix     = _gl.getUniformLocation( _sprite.program, "projectionMatrix" );

	//_gl.enableVertexAttribArray( _sprite.attributes.position );
	//_gl.enableVertexAttribArray( _sprite.attributes.uv );

	var _spriteAttributesEnabled = false;

	this.setSize = function ( width, height ) {

		_canvas.width = width;
		_canvas.height = height;

		this.setViewport( 0, 0, _canvas.width, _canvas.height );

	};

	this.setViewport = function ( x, y, width, height ) {

		_viewportX = x;
		_viewportY = y;

		_viewportWidth = width;
		_viewportHeight = height;

		_gl.viewport( _viewportX, _viewportY, _viewportWidth, _viewportHeight );

	};

	this.setScissor = function ( x, y, width, height ) {

		_gl.scissor( x, y, width, height );

	};

	this.enableScissorTest = function ( enable ) {

		if ( enable )
			_gl.enable( _gl.SCISSOR_TEST );
		else
			_gl.disable( _gl.SCISSOR_TEST );

	};

	this.enableDepthBufferWrite = function ( enable ) {

		_currentDepthMask = enable;
		_gl.depthMask( enable );

	};

	this.setClearColorHex = function ( hex, alpha ) {

		_clearColor.setHex( hex );
		_clearAlpha = alpha;

		_gl.clearColor( _clearColor.r, _clearColor.g, _clearColor.b, _clearAlpha );

	};

	this.setClearColor = function ( color, alpha ) {

		_clearColor.copy( color );
		_clearAlpha = alpha;

		_gl.clearColor( _clearColor.r, _clearColor.g, _clearColor.b, _clearAlpha );

	};

	this.clear = function () {

		_gl.clear( _gl.COLOR_BUFFER_BIT | _gl.DEPTH_BUFFER_BIT | _gl.STENCIL_BUFFER_BIT );

	};

	this.getContext = function() {

		return _gl;

	};

	function setupLights ( program, lights ) {

		var l, ll, light, n,
		r = 0, g = 0, b = 0,
		color, position, intensity, distance,

		zlights = _lights,

		dcolors = zlights.directional.colors,
		dpositions = zlights.directional.positions,

		pcolors = zlights.point.colors,
		ppositions = zlights.point.positions,
		pdistances = zlights.point.distances,

		dlength = 0,
		plength = 0,

		doffset = 0,
		poffset = 0;

		for ( l = 0, ll = lights.length; l < ll; l++ ) {

			light = lights[ l ];
			color = light.color;

			position = light.position;
			intensity = light.intensity;
			distance = light.distance;

			if ( light instanceof THREE.AmbientLight ) {

				r += color.r;
				g += color.g;
				b += color.b;

			} else if ( light instanceof THREE.DirectionalLight ) {

				doffset = dlength * 3;

				dcolors[ doffset ]     = color.r * intensity;
				dcolors[ doffset + 1 ] = color.g * intensity;
				dcolors[ doffset + 2 ] = color.b * intensity;

				dpositions[ doffset ]     = position.x;
				dpositions[ doffset + 1 ] = position.y;
				dpositions[ doffset + 2 ] = position.z;

				dlength += 1;

			} else if ( light instanceof THREE.SpotLight ) { // hack, not a proper spotlight

				doffset = dlength * 3;

				dcolors[ doffset ]     = color.r * intensity;
				dcolors[ doffset + 1 ] = color.g * intensity;
				dcolors[ doffset + 2 ] = color.b * intensity;

				n = 1 / position.length();

				dpositions[ doffset ]     = position.x * n;
				dpositions[ doffset + 1 ] = position.y * n;
				dpositions[ doffset + 2 ] = position.z * n;

				dlength += 1;

			} else if( light instanceof THREE.PointLight ) {

				poffset = plength * 3;

				pcolors[ poffset ]     = color.r * intensity;
				pcolors[ poffset + 1 ] = color.g * intensity;
				pcolors[ poffset + 2 ] = color.b * intensity;

				ppositions[ poffset ]     = position.x;
				ppositions[ poffset + 1 ] = position.y;
				ppositions[ poffset + 2 ] = position.z;

				pdistances[ plength ] = distance;

				plength += 1;

			}

		}

		// null eventual remains from removed lights
		// (this is to avoid if in shader)

		for( l = dlength * 3; l < dcolors.length; l++ ) dcolors[ l ] = 0.0;
		for( l = plength * 3; l < pcolors.length; l++ ) pcolors[ l ] = 0.0;

		zlights.point.length = plength;
		zlights.directional.length = dlength;

		zlights.ambient[ 0 ] = r;
		zlights.ambient[ 1 ] = g;
		zlights.ambient[ 2 ] = b;

	};

	function createParticleBuffers ( geometry ) {

		geometry.__webglVertexBuffer = _gl.createBuffer();
		geometry.__webglColorBuffer = _gl.createBuffer();

	};

	function createLineBuffers( geometry ) {

		geometry.__webglVertexBuffer = _gl.createBuffer();
		geometry.__webglColorBuffer = _gl.createBuffer();

	};

	function createRibbonBuffers( geometry ) {

		geometry.__webglVertexBuffer = _gl.createBuffer();
		geometry.__webglColorBuffer = _gl.createBuffer();

	};

	function createMeshBuffers( geometryGroup ) {

		geometryGroup.__webglVertexBuffer = _gl.createBuffer();
		geometryGroup.__webglNormalBuffer = _gl.createBuffer();
		geometryGroup.__webglTangentBuffer = _gl.createBuffer();
		geometryGroup.__webglColorBuffer = _gl.createBuffer();
		geometryGroup.__webglUVBuffer = _gl.createBuffer();
		geometryGroup.__webglUV2Buffer = _gl.createBuffer();

		geometryGroup.__webglSkinVertexABuffer = _gl.createBuffer();
		geometryGroup.__webglSkinVertexBBuffer = _gl.createBuffer();
		geometryGroup.__webglSkinIndicesBuffer = _gl.createBuffer();
		geometryGroup.__webglSkinWeightsBuffer = _gl.createBuffer();

		geometryGroup.__webglFaceBuffer = _gl.createBuffer();
		geometryGroup.__webglLineBuffer = _gl.createBuffer();

		if ( geometryGroup.numMorphTargets ) {

			var m, ml;

			geometryGroup.__webglMorphTargetsBuffers = [];

			for ( m = 0, ml = geometryGroup.numMorphTargets; m < ml; m ++ ) {

				geometryGroup.__webglMorphTargetsBuffers.push( _gl.createBuffer() );

			}

		}

	};

	function initLineBuffers ( geometry ) {

		var nvertices = geometry.vertices.length;

		geometry.__vertexArray = new Float32Array( nvertices * 3 );
		geometry.__colorArray = new Float32Array( nvertices * 3 );

		geometry.__webglLineCount = nvertices;

	};

	function initRibbonBuffers ( geometry ) {

		var nvertices = geometry.vertices.length;

		geometry.__vertexArray = new Float32Array( nvertices * 3 );
		geometry.__colorArray = new Float32Array( nvertices * 3 );

		geometry.__webglVertexCount = nvertices;

	};

	function initParticleBuffers ( geometry, object ) {

		var nvertices = geometry.vertices.length;

		geometry.__vertexArray = new Float32Array( nvertices * 3 );
		geometry.__colorArray = new Float32Array( nvertices * 3 );

		geometry.__sortArray = [];

		geometry.__webglParticleCount = nvertices;

		geometry.__materials = object.materials;

		// custom attributes

		var m, ml, material;

		for ( m = 0, ml = object.materials.length; m < ml; m ++ ) {

			material = object.materials[ m ];

			if ( material.attributes ) {

				if ( geometry.__webglCustomAttributes === undefined ) {

					geometry.__webglCustomAttributes = {};

				}

				for ( a in material.attributes ) {

					// Do a shallow copy of the attribute object so different geometryGroup chunks use different
					// attribute buffers which are correctly indexed in the setMeshBuffers function

					// Not sure how to best translate this into non-indexed arrays
					// used for particles, as there are no geometry chunks here
					// Probably could be simplified

					originalAttribute = material.attributes[ a ];

					attribute = {};

					for ( property in originalAttribute ) {

						attribute[ property ] = originalAttribute[ property ];

					}

					if( !attribute.__webglInitialized || attribute.createUniqueBuffers ) {

						attribute.__webglInitialized = true;

						size = 1;		// "f" and "i"

						if( attribute.type === "v2" ) size = 2;
						else if( attribute.type === "v3" ) size = 3;
						else if( attribute.type === "v4" ) size = 4;
						else if( attribute.type === "c"  ) size = 3;

						attribute.size = size;
						attribute.array = new Float32Array( nvertices * size );
						attribute.buffer = _gl.createBuffer();
						attribute.buffer.belongsToAttribute = a;

						originalAttribute.needsUpdate = true;
						attribute.__original = originalAttribute;

					}

					geometry.__webglCustomAttributes[ a ] = attribute;

				}

			}

		}

	};

	function initMeshBuffers ( geometryGroup, object ) {

		var f, fl, fi, face,
		m, ml, size,
		nvertices = 0, ntris = 0, nlines = 0,

		uvType,
		vertexColorType,
		normalType,
		materials, material,
		attribute, property, originalAttribute,

		geometry = object.geometry,
		obj_faces = geometry.faces,
		chunk_faces = geometryGroup.faces;

		for ( f = 0, fl = chunk_faces.length; f < fl; f++ ) {

			fi = chunk_faces[ f ];
			face = obj_faces[ fi ];

			if ( face instanceof THREE.Face3 ) {

				nvertices += 3;
				ntris += 1;
				nlines += 3;

			} else if ( face instanceof THREE.Face4 ) {

				nvertices += 4;
				ntris += 2;
				nlines += 4;

			}

		}

		materials = unrollGroupMaterials( geometryGroup, object );

		// this will not work if materials would change in run-time
		// it should be refreshed every frame
		// but need to do unrollGroupMaterials
		// more properly without push to array
		// like unrollBufferMaterials

		geometryGroup.__materials = materials;

		uvType = bufferGuessUVType( materials, geometryGroup, object );
		normalType = bufferGuessNormalType( materials, geometryGroup, object );
		vertexColorType = bufferGuessVertexColorType( materials, geometryGroup, object );

		//console.log("uvType",uvType, "normalType",normalType, "vertexColorType",vertexColorType, object, geometryGroup, materials );

		geometryGroup.__vertexArray = new Float32Array( nvertices * 3 );

		if ( normalType ) {

			geometryGroup.__normalArray = new Float32Array( nvertices * 3 );

		}

		if ( geometry.hasTangents ) {

			geometryGroup.__tangentArray = new Float32Array( nvertices * 4 );

		}

		if ( vertexColorType ) {

			geometryGroup.__colorArray = new Float32Array( nvertices * 3 );

		}

		if ( uvType ) {

			if ( geometry.faceUvs.length > 0 || geometry.faceVertexUvs.length > 0 ) {

				geometryGroup.__uvArray = new Float32Array( nvertices * 2 );

			}

			if ( geometry.faceUvs.length > 1 || geometry.faceVertexUvs.length > 1 ) {

				geometryGroup.__uv2Array = new Float32Array( nvertices * 2 );

			}

		}

		if ( object.geometry.skinWeights.length && object.geometry.skinIndices.length ) {

			geometryGroup.__skinVertexAArray = new Float32Array( nvertices * 4 );
			geometryGroup.__skinVertexBArray = new Float32Array( nvertices * 4 );
			geometryGroup.__skinIndexArray = new Float32Array( nvertices * 4 );
			geometryGroup.__skinWeightArray = new Float32Array( nvertices * 4 );

		}

		geometryGroup.__faceArray = new Uint16Array( ntris * 3 + ( object.geometry.edgeFaces ? object.geometry.edgeFaces.length * 2 * 3 : 0 ));
		geometryGroup.__lineArray = new Uint16Array( nlines * 2 );

		if ( geometryGroup.numMorphTargets ) {

			geometryGroup.__morphTargetsArrays = [];

			for ( m = 0, ml = geometryGroup.numMorphTargets; m < ml; m ++ ) {

				geometryGroup.__morphTargetsArrays.push( new Float32Array( nvertices * 3 ) );

			}

		}

		geometryGroup.__needsSmoothNormals = ( normalType == THREE.SmoothShading );

		geometryGroup.__uvType = uvType;
		geometryGroup.__vertexColorType = vertexColorType;
		geometryGroup.__normalType = normalType;

		geometryGroup.__webglFaceCount = ntris * 3 + ( object.geometry.edgeFaces ? object.geometry.edgeFaces.length * 2 * 3 : 0 );
		geometryGroup.__webglLineCount = nlines * 2;


		// custom attributes

		for ( m = 0, ml = materials.length; m < ml; m ++ ) {

			material = materials[ m ];

			if ( material.attributes ) {

				if ( geometryGroup.__webglCustomAttributes === undefined ) {

					geometryGroup.__webglCustomAttributes = {};

				}

				for ( a in material.attributes ) {

					// Do a shallow copy of the attribute object so different geometryGroup chunks use different
					// attribute buffers which are correctly indexed in the setMeshBuffers function

					originalAttribute = material.attributes[ a ];

					attribute = {};

					for ( property in originalAttribute ) {

						attribute[ property ] = originalAttribute[ property ];

					}

					if( !attribute.__webglInitialized || attribute.createUniqueBuffers ) {

						attribute.__webglInitialized = true;

						size = 1;		// "f" and "i"

						if( attribute.type === "v2" ) size = 2;
						else if( attribute.type === "v3" ) size = 3;
						else if( attribute.type === "v4" ) size = 4;
						else if( attribute.type === "c"  ) size = 3;

						attribute.size = size;
						attribute.array = new Float32Array( nvertices * size );
						attribute.buffer = _gl.createBuffer();
						attribute.buffer.belongsToAttribute = a;

						originalAttribute.needsUpdate = true;
						attribute.__original = originalAttribute;

					}

					geometryGroup.__webglCustomAttributes[ a ] = attribute;

				}

			}

		}

		geometryGroup.__inittedArrays = true;

	};


	function setMeshBuffers( geometryGroup, object, hint, dispose ) {

		if ( ! geometryGroup.__inittedArrays ) {

			// console.log( object );
			return;

		}

		var f, fl, fi, face,
		vertexNormals, faceNormal, normal,
		vertexColors, faceColor,
		vertexTangents,
		uvType, vertexColorType, normalType,
		uv, uv2, v1, v2, v3, v4, t1, t2, t3, t4,
		c1, c2, c3, c4,
		sw1, sw2, sw3, sw4,
		si1, si2, si3, si4,
		sa1, sa2, sa3, sa4,
		sb1, sb2, sb3, sb4,
		m, ml, i,
		vn, uvi, uv2i,
		vk, vkl, vka,
		a,

		vertexIndex = 0,

		offset = 0,
		offset_uv = 0,
		offset_uv2 = 0,
		offset_face = 0,
		offset_normal = 0,
		offset_tangent = 0,
		offset_line = 0,
		offset_color = 0,
		offset_skin = 0,
		offset_morphTarget = 0,
		offset_custom = 0,
		offset_customSrc = 0,

		value,

		vertexArray = geometryGroup.__vertexArray,
		uvArray = geometryGroup.__uvArray,
		uv2Array = geometryGroup.__uv2Array,
		normalArray = geometryGroup.__normalArray,
		tangentArray = geometryGroup.__tangentArray,
		colorArray = geometryGroup.__colorArray,

		skinVertexAArray = geometryGroup.__skinVertexAArray,
		skinVertexBArray = geometryGroup.__skinVertexBArray,
		skinIndexArray = geometryGroup.__skinIndexArray,
		skinWeightArray = geometryGroup.__skinWeightArray,

		morphTargetsArrays = geometryGroup.__morphTargetsArrays,

		customAttributes = geometryGroup.__webglCustomAttributes,
		customAttribute,

		faceArray = geometryGroup.__faceArray,
		lineArray = geometryGroup.__lineArray,

		needsSmoothNormals = geometryGroup.__needsSmoothNormals,

		vertexColorType = geometryGroup.__vertexColorType,
		uvType = geometryGroup.__uvType,
		normalType = geometryGroup.__normalType,

		geometry = object.geometry, // this is shared for all chunks

		dirtyVertices = geometry.__dirtyVertices,
		dirtyElements = geometry.__dirtyElements,
		dirtyUvs = geometry.__dirtyUvs,
		dirtyNormals = geometry.__dirtyNormals,
		dirtyTangents = geometry.__dirtyTangents,
		dirtyColors = geometry.__dirtyColors,
		dirtyMorphTargets = geometry.__dirtyMorphTargets,

		vertices = geometry.vertices,
		chunk_faces = geometryGroup.faces,
		obj_faces = geometry.faces,

		obj_uvs  = geometry.faceVertexUvs[ 0 ],
		obj_uvs2 = geometry.faceVertexUvs[ 1 ],

		obj_colors = geometry.colors,

		obj_skinVerticesA = geometry.skinVerticesA,
		obj_skinVerticesB = geometry.skinVerticesB,
		obj_skinIndices = geometry.skinIndices,
		obj_skinWeights = geometry.skinWeights,

		morphTargets = geometry.morphTargets;

		if ( customAttributes ) {

			for ( a in customAttributes ) {

				customAttributes[ a ].offset = 0;
				customAttributes[ a ].offsetSrc = 0;

			}

		}


		for ( f = 0, fl = chunk_faces.length; f < fl; f ++ ) {

			fi = chunk_faces[ f ];
			face = obj_faces[ fi ];

			if ( obj_uvs ) {

				uv = obj_uvs[ fi ];

			}

			if ( obj_uvs2 ) {

				uv2 = obj_uvs2[ fi ];

			}

			vertexNormals = face.vertexNormals;
			faceNormal = face.normal;

			vertexColors = face.vertexColors;
			faceColor = face.color;

			vertexTangents = face.vertexTangents;

			if ( face instanceof THREE.Face3 ) {

				if ( dirtyVertices ) {

					v1 = vertices[ face.a ].position;
					v2 = vertices[ face.b ].position;
					v3 = vertices[ face.c ].position;

					vertexArray[ offset ]     = v1.x;
					vertexArray[ offset + 1 ] = v1.y;
					vertexArray[ offset + 2 ] = v1.z;

					vertexArray[ offset + 3 ] = v2.x;
					vertexArray[ offset + 4 ] = v2.y;
					vertexArray[ offset + 5 ] = v2.z;

					vertexArray[ offset + 6 ] = v3.x;
					vertexArray[ offset + 7 ] = v3.y;
					vertexArray[ offset + 8 ] = v3.z;

					offset += 9;

				}

				if ( customAttributes ) {

					for ( a in customAttributes ) {

						customAttribute = customAttributes[ a ];

						if ( customAttribute.__original.needsUpdate ) {

							offset_custom = customAttribute.offset;
							offset_customSrc = customAttribute.offsetSrc;

							if ( customAttribute.size === 1 ) {

								if ( customAttribute.boundTo === undefined || customAttribute.boundTo === "vertices" ) {

									customAttribute.array[ offset_custom ] 	   = customAttribute.value[ face.a ];
									customAttribute.array[ offset_custom + 1 ] = customAttribute.value[ face.b ];
									customAttribute.array[ offset_custom + 2 ] = customAttribute.value[ face.c ];

								} else if ( customAttribute.boundTo === "faces" ) {

									value = customAttribute.value[ offset_customSrc ];

									customAttribute.array[ offset_custom ] 	   = value;
									customAttribute.array[ offset_custom + 1 ] = value;
									customAttribute.array[ offset_custom + 2 ] = value;

									customAttribute.offsetSrc ++;

								} else if ( customAttribute.boundTo === "faceVertices" ) {

									customAttribute.array[ offset_custom ] 	   = customAttribute.value[ offset_customSrc ];
									customAttribute.array[ offset_custom + 1 ] = customAttribute.value[ offset_customSrc + 1 ];
									customAttribute.array[ offset_custom + 2 ] = customAttribute.value[ offset_customSrc + 2 ];

									customAttribute.offsetSrc += 3;

								}

								customAttribute.offset += 3;

							} else {

								if ( customAttribute.boundTo === undefined || customAttribute.boundTo === "vertices" ) {

									v1 = customAttribute.value[ face.a ];
									v2 = customAttribute.value[ face.b ];
									v3 = customAttribute.value[ face.c ];

								} else if ( customAttribute.boundTo === "faces" ) {

									value = customAttribute.value[ offset_customSrc ];

									v1 = value;
									v2 = value;
									v3 = value;

									customAttribute.offsetSrc ++;

								} else if ( customAttribute.boundTo === "faceVertices" ) {

									v1 = customAttribute.value[ offset_customSrc ];
									v2 = customAttribute.value[ offset_customSrc + 1 ];
									v3 = customAttribute.value[ offset_customSrc + 2 ];

									customAttribute.offsetSrc += 3;

								}


								if ( customAttribute.size === 2 ) {

									customAttribute.array[ offset_custom ] 	   = v1.x;
									customAttribute.array[ offset_custom + 1 ] = v1.y;

									customAttribute.array[ offset_custom + 2 ] = v2.x;
									customAttribute.array[ offset_custom + 3 ] = v2.y;

									customAttribute.array[ offset_custom + 4 ] = v3.x;
									customAttribute.array[ offset_custom + 5 ] = v3.y;

									customAttribute.offset += 6;

								} else if ( customAttribute.size === 3 ) {

									if ( customAttribute.type === "c" ) {

										customAttribute.array[ offset_custom ] 	   = v1.r;
										customAttribute.array[ offset_custom + 1 ] = v1.g;
										customAttribute.array[ offset_custom + 2 ] = v1.b;

										customAttribute.array[ offset_custom + 3 ] = v2.r;
										customAttribute.array[ offset_custom + 4 ] = v2.g;
										customAttribute.array[ offset_custom + 5 ] = v2.b;

										customAttribute.array[ offset_custom + 6 ] = v3.r;
										customAttribute.array[ offset_custom + 7 ] = v3.g;
										customAttribute.array[ offset_custom + 8 ] = v3.b;

									} else {

										customAttribute.array[ offset_custom ] 	   = v1.x;
										customAttribute.array[ offset_custom + 1 ] = v1.y;
										customAttribute.array[ offset_custom + 2 ] = v1.z;

										customAttribute.array[ offset_custom + 3 ] = v2.x;
										customAttribute.array[ offset_custom + 4 ] = v2.y;
										customAttribute.array[ offset_custom + 5 ] = v2.z;

										customAttribute.array[ offset_custom + 6 ] = v3.x;
										customAttribute.array[ offset_custom + 7 ] = v3.y;
										customAttribute.array[ offset_custom + 8 ] = v3.z;

									}

									customAttribute.offset += 9;

								} else {

									customAttribute.array[ offset_custom  ] 	= v1.x;
									customAttribute.array[ offset_custom + 1  ] = v1.y;
									customAttribute.array[ offset_custom + 2  ] = v1.z;
									customAttribute.array[ offset_custom + 3  ] = v1.w;

									customAttribute.array[ offset_custom + 4  ] = v2.x;
									customAttribute.array[ offset_custom + 5  ] = v2.y;
									customAttribute.array[ offset_custom + 6  ] = v2.z;
									customAttribute.array[ offset_custom + 7  ] = v2.w;

									customAttribute.array[ offset_custom + 8  ] = v3.x;
									customAttribute.array[ offset_custom + 9  ] = v3.y;
									customAttribute.array[ offset_custom + 10 ] = v3.z;
									customAttribute.array[ offset_custom + 11 ] = v3.w;

									customAttribute.offset += 12;

								}

							}

						}

					}

				}


				if ( dirtyMorphTargets ) {

					for ( vk = 0, vkl = morphTargets.length; vk < vkl; vk ++ ) {

						v1 = morphTargets[ vk ].vertices[ face.a ].position;
						v2 = morphTargets[ vk ].vertices[ face.b ].position;
						v3 = morphTargets[ vk ].vertices[ face.c ].position;

						vka = morphTargetsArrays[ vk ];

						vka[ offset_morphTarget ] 	  = v1.x;
						vka[ offset_morphTarget + 1 ] = v1.y;
						vka[ offset_morphTarget + 2 ] = v1.z;

						vka[ offset_morphTarget + 3 ] = v2.x;
						vka[ offset_morphTarget + 4 ] = v2.y;
						vka[ offset_morphTarget + 5 ] = v2.z;

						vka[ offset_morphTarget + 6 ] = v3.x;
						vka[ offset_morphTarget + 7 ] = v3.y;
						vka[ offset_morphTarget + 8 ] = v3.z;

					}

					offset_morphTarget += 9;

				}

				if ( obj_skinWeights.length ) {

					// weights

					sw1 = obj_skinWeights[ face.a ];
					sw2 = obj_skinWeights[ face.b ];
					sw3 = obj_skinWeights[ face.c ];

					skinWeightArray[ offset_skin ]     = sw1.x;
					skinWeightArray[ offset_skin + 1 ] = sw1.y;
					skinWeightArray[ offset_skin + 2 ] = sw1.z;
					skinWeightArray[ offset_skin + 3 ] = sw1.w;

					skinWeightArray[ offset_skin + 4 ] = sw2.x;
					skinWeightArray[ offset_skin + 5 ] = sw2.y;
					skinWeightArray[ offset_skin + 6 ] = sw2.z;
					skinWeightArray[ offset_skin + 7 ] = sw2.w;

					skinWeightArray[ offset_skin + 8 ]  = sw3.x;
					skinWeightArray[ offset_skin + 9 ]  = sw3.y;
					skinWeightArray[ offset_skin + 10 ] = sw3.z;
					skinWeightArray[ offset_skin + 11 ] = sw3.w;

					// indices

					si1 = obj_skinIndices[ face.a ];
					si2 = obj_skinIndices[ face.b ];
					si3 = obj_skinIndices[ face.c ];

					skinIndexArray[ offset_skin ]     = si1.x;
					skinIndexArray[ offset_skin + 1 ] = si1.y;
					skinIndexArray[ offset_skin + 2 ] = si1.z;
					skinIndexArray[ offset_skin + 3 ] = si1.w;

					skinIndexArray[ offset_skin + 4 ] = si2.x;
					skinIndexArray[ offset_skin + 5 ] = si2.y;
					skinIndexArray[ offset_skin + 6 ] = si2.z;
					skinIndexArray[ offset_skin + 7 ] = si2.w;

					skinIndexArray[ offset_skin + 8 ]  = si3.x;
					skinIndexArray[ offset_skin + 9 ]  = si3.y;
					skinIndexArray[ offset_skin + 10 ] = si3.z;
					skinIndexArray[ offset_skin + 11 ] = si3.w;

					// vertices A

					sa1 = obj_skinVerticesA[ face.a ];
					sa2 = obj_skinVerticesA[ face.b ];
					sa3 = obj_skinVerticesA[ face.c ];

					skinVertexAArray[ offset_skin ]     = sa1.x;
					skinVertexAArray[ offset_skin + 1 ] = sa1.y;
					skinVertexAArray[ offset_skin + 2 ] = sa1.z;
					skinVertexAArray[ offset_skin + 3 ] = 1; // pad for faster vertex shader

					skinVertexAArray[ offset_skin + 4 ] = sa2.x;
					skinVertexAArray[ offset_skin + 5 ] = sa2.y;
					skinVertexAArray[ offset_skin + 6 ] = sa2.z;
					skinVertexAArray[ offset_skin + 7 ] = 1;

					skinVertexAArray[ offset_skin + 8 ]  = sa3.x;
					skinVertexAArray[ offset_skin + 9 ]  = sa3.y;
					skinVertexAArray[ offset_skin + 10 ] = sa3.z;
					skinVertexAArray[ offset_skin + 11 ] = 1;

					// vertices B

					sb1 = obj_skinVerticesB[ face.a ];
					sb2 = obj_skinVerticesB[ face.b ];
					sb3 = obj_skinVerticesB[ face.c ];

					skinVertexBArray[ offset_skin ]     = sb1.x;
					skinVertexBArray[ offset_skin + 1 ] = sb1.y;
					skinVertexBArray[ offset_skin + 2 ] = sb1.z;
					skinVertexBArray[ offset_skin + 3 ] = 1; // pad for faster vertex shader

					skinVertexBArray[ offset_skin + 4 ] = sb2.x;
					skinVertexBArray[ offset_skin + 5 ] = sb2.y;
					skinVertexBArray[ offset_skin + 6 ] = sb2.z;
					skinVertexBArray[ offset_skin + 7 ] = 1;

					skinVertexBArray[ offset_skin + 8 ]  = sb3.x;
					skinVertexBArray[ offset_skin + 9 ]  = sb3.y;
					skinVertexBArray[ offset_skin + 10 ] = sb3.z;
					skinVertexBArray[ offset_skin + 11 ] = 1;

					offset_skin += 12;

				}

				if ( dirtyColors && vertexColorType ) {

					if ( vertexColors.length == 3 && vertexColorType == THREE.VertexColors ) {

						c1 = vertexColors[ 0 ];
						c2 = vertexColors[ 1 ];
						c3 = vertexColors[ 2 ];

					} else {

						c1 = faceColor;
						c2 = faceColor;
						c3 = faceColor;

					}

					colorArray[ offset_color ]     = c1.r;
					colorArray[ offset_color + 1 ] = c1.g;
					colorArray[ offset_color + 2 ] = c1.b;

					colorArray[ offset_color + 3 ] = c2.r;
					colorArray[ offset_color + 4 ] = c2.g;
					colorArray[ offset_color + 5 ] = c2.b;

					colorArray[ offset_color + 6 ] = c3.r;
					colorArray[ offset_color + 7 ] = c3.g;
					colorArray[ offset_color + 8 ] = c3.b;

					offset_color += 9;

				}

				if ( dirtyTangents && geometry.hasTangents ) {

					t1 = vertexTangents[ 0 ];
					t2 = vertexTangents[ 1 ];
					t3 = vertexTangents[ 2 ];

					tangentArray[ offset_tangent ]     = t1.x;
					tangentArray[ offset_tangent + 1 ] = t1.y;
					tangentArray[ offset_tangent + 2 ] = t1.z;
					tangentArray[ offset_tangent + 3 ] = t1.w;

					tangentArray[ offset_tangent + 4 ] = t2.x;
					tangentArray[ offset_tangent + 5 ] = t2.y;
					tangentArray[ offset_tangent + 6 ] = t2.z;
					tangentArray[ offset_tangent + 7 ] = t2.w;

					tangentArray[ offset_tangent + 8 ]  = t3.x;
					tangentArray[ offset_tangent + 9 ]  = t3.y;
					tangentArray[ offset_tangent + 10 ] = t3.z;
					tangentArray[ offset_tangent + 11 ] = t3.w;

					offset_tangent += 12;

				}

				if ( dirtyNormals && normalType ) {

					if ( vertexNormals.length == 3 && needsSmoothNormals ) {

						for ( i = 0; i < 3; i ++ ) {

							vn = vertexNormals[ i ];

							normalArray[ offset_normal ]     = vn.x;
							normalArray[ offset_normal + 1 ] = vn.y;
							normalArray[ offset_normal + 2 ] = vn.z;

							offset_normal += 3;

						}

					} else {

						for ( i = 0; i < 3; i ++ ) {

							normalArray[ offset_normal ]     = faceNormal.x;
							normalArray[ offset_normal + 1 ] = faceNormal.y;
							normalArray[ offset_normal + 2 ] = faceNormal.z;

							offset_normal += 3;

						}

					}

				}

				if ( dirtyUvs && uv !== undefined && uvType ) {

					for ( i = 0; i < 3; i ++ ) {

						uvi = uv[ i ];

						uvArray[ offset_uv ]     = uvi.u;
						uvArray[ offset_uv + 1 ] = uvi.v;

						offset_uv += 2;

					}

				}

				if ( dirtyUvs && uv2 !== undefined && uvType ) {

					for ( i = 0; i < 3; i ++ ) {

						uv2i = uv2[ i ];

						uv2Array[ offset_uv2 ]     = uv2i.u;
						uv2Array[ offset_uv2 + 1 ] = uv2i.v;

						offset_uv2 += 2;

					}

				}

				if ( dirtyElements ) {

					faceArray[ offset_face ] 	 = vertexIndex;
					faceArray[ offset_face + 1 ] = vertexIndex + 1;
					faceArray[ offset_face + 2 ] = vertexIndex + 2;

					offset_face += 3;

					lineArray[ offset_line ]     = vertexIndex;
					lineArray[ offset_line + 1 ] = vertexIndex + 1;

					lineArray[ offset_line + 2 ] = vertexIndex;
					lineArray[ offset_line + 3 ] = vertexIndex + 2;

					lineArray[ offset_line + 4 ] = vertexIndex + 1;
					lineArray[ offset_line + 5 ] = vertexIndex + 2;

					offset_line += 6;

					vertexIndex += 3;

				}


			} else if ( face instanceof THREE.Face4 ) {

				if ( dirtyVertices ) {

					v1 = vertices[ face.a ].position;
					v2 = vertices[ face.b ].position;
					v3 = vertices[ face.c ].position;
					v4 = vertices[ face.d ].position;

					vertexArray[ offset ]     = v1.x;
					vertexArray[ offset + 1 ] = v1.y;
					vertexArray[ offset + 2 ] = v1.z;

					vertexArray[ offset + 3 ] = v2.x;
					vertexArray[ offset + 4 ] = v2.y;
					vertexArray[ offset + 5 ] = v2.z;

					vertexArray[ offset + 6 ] = v3.x;
					vertexArray[ offset + 7 ] = v3.y;
					vertexArray[ offset + 8 ] = v3.z;

					vertexArray[ offset + 9 ]  = v4.x;
					vertexArray[ offset + 10 ] = v4.y;
					vertexArray[ offset + 11 ] = v4.z;

					offset += 12;

				}

				if ( customAttributes ) {

					for ( a in customAttributes ) {

						customAttribute = customAttributes[ a ];

						if ( customAttribute.__original.needsUpdate ) {

							offset_custom = customAttribute.offset;
							offset_customSrc = customAttribute.offsetSrc;

							if ( customAttribute.size === 1 ) {

								if ( customAttribute.boundTo === undefined || customAttribute.boundTo === "vertices" ) {

									customAttribute.array[ offset_custom ] 	   = customAttribute.value[ face.a ];
									customAttribute.array[ offset_custom + 1 ] = customAttribute.value[ face.b ];
									customAttribute.array[ offset_custom + 2 ] = customAttribute.value[ face.c ];
									customAttribute.array[ offset_custom + 3 ] = customAttribute.value[ face.d ];

								} else if ( customAttribute.boundTo === "faces" ) {

									value = customAttribute.value[ offset_customSrc ];

									customAttribute.array[ offset_custom ] 	   = value;
									customAttribute.array[ offset_custom + 1 ] = value;
									customAttribute.array[ offset_custom + 2 ] = value;
									customAttribute.array[ offset_custom + 3 ] = value;

									customAttribute.offsetSrc ++;

								} else if ( customAttribute.boundTo === "faceVertices" ) {

									customAttribute.array[ offset_custom ] 	   = customAttribute.value[ offset_customSrc ];
									customAttribute.array[ offset_custom + 1 ] = customAttribute.value[ offset_customSrc + 1 ];
									customAttribute.array[ offset_custom + 2 ] = customAttribute.value[ offset_customSrc + 2 ];
									customAttribute.array[ offset_custom + 3 ] = customAttribute.value[ offset_customSrc + 3 ];

									customAttribute.offsetSrc += 4;

								}

								customAttribute.offset += 4;

							} else {

								if ( customAttribute.boundTo === undefined || customAttribute.boundTo === "vertices" ) {

									v1 = customAttribute.value[ face.a ];
									v2 = customAttribute.value[ face.b ];
									v3 = customAttribute.value[ face.c ];
									v4 = customAttribute.value[ face.d ];

								} else if ( customAttribute.boundTo === "faces" ) {

									value = customAttribute.value[ offset_customSrc ];

									v1 = value;
									v2 = value;
									v3 = value;
									v4 = value;

									customAttribute.offsetSrc ++;

								} else if ( customAttribute.boundTo === "faceVertices" ) {

									v1 = customAttribute.value[ offset_customSrc ];
									v2 = customAttribute.value[ offset_customSrc + 1 ];
									v3 = customAttribute.value[ offset_customSrc + 2 ];
									v4 = customAttribute.value[ offset_customSrc + 3 ];

									customAttribute.offsetSrc += 4;

								}


								if ( customAttribute.size === 2 ) {

									customAttribute.array[ offset_custom ] 	   = v1.x;
									customAttribute.array[ offset_custom + 1 ] = v1.y;

									customAttribute.array[ offset_custom + 2 ] = v2.x;
									customAttribute.array[ offset_custom + 3 ] = v2.y;

									customAttribute.array[ offset_custom + 4 ] = v3.x;
									customAttribute.array[ offset_custom + 5 ] = v3.y;

									customAttribute.array[ offset_custom + 6 ] = v4.x;
									customAttribute.array[ offset_custom + 7 ] = v4.y;

									customAttribute.offset += 8;

								} else if ( customAttribute.size === 3 ) {

									if ( customAttribute.type === "c" ) {

										customAttribute.array[ offset_custom  ] 	= v1.r;
										customAttribute.array[ offset_custom + 1  ] = v1.g;
										customAttribute.array[ offset_custom + 2  ] = v1.b;

										customAttribute.array[ offset_custom + 3  ] = v2.r;
										customAttribute.array[ offset_custom + 4  ] = v2.g;
										customAttribute.array[ offset_custom + 5  ] = v2.b;

										customAttribute.array[ offset_custom + 6  ] = v3.r;
										customAttribute.array[ offset_custom + 7  ] = v3.g;
										customAttribute.array[ offset_custom + 8  ] = v3.b;

										customAttribute.array[ offset_custom + 9  ] = v4.r;
										customAttribute.array[ offset_custom + 10 ] = v4.g;
										customAttribute.array[ offset_custom + 11 ] = v4.b;

									} else {

										customAttribute.array[ offset_custom  ] 	= v1.x;
										customAttribute.array[ offset_custom + 1  ] = v1.y;
										customAttribute.array[ offset_custom + 2  ] = v1.z;

										customAttribute.array[ offset_custom + 3  ] = v2.x;
										customAttribute.array[ offset_custom + 4  ] = v2.y;
										customAttribute.array[ offset_custom + 5  ] = v2.z;

										customAttribute.array[ offset_custom + 6  ] = v3.x;
										customAttribute.array[ offset_custom + 7  ] = v3.y;
										customAttribute.array[ offset_custom + 8  ] = v3.z;

										customAttribute.array[ offset_custom + 9  ] = v4.x;
										customAttribute.array[ offset_custom + 10 ] = v4.y;
										customAttribute.array[ offset_custom + 11 ] = v4.z;

									}

									customAttribute.offset += 12;

								} else {

									customAttribute.array[ offset_custom  ] 	= v1.x;
									customAttribute.array[ offset_custom + 1  ] = v1.y;
									customAttribute.array[ offset_custom + 2  ] = v1.z;
									customAttribute.array[ offset_custom + 3  ] = v1.w;

									customAttribute.array[ offset_custom + 4  ] = v2.x;
									customAttribute.array[ offset_custom + 5  ] = v2.y;
									customAttribute.array[ offset_custom + 6  ] = v2.z;
									customAttribute.array[ offset_custom + 7  ] = v2.w;

									customAttribute.array[ offset_custom + 8  ] = v3.x;
									customAttribute.array[ offset_custom + 9  ] = v3.y;
									customAttribute.array[ offset_custom + 10 ] = v3.z;
									customAttribute.array[ offset_custom + 11 ] = v3.w;

									customAttribute.array[ offset_custom + 12 ] = v4.x;
									customAttribute.array[ offset_custom + 13 ] = v4.y;
									customAttribute.array[ offset_custom + 14 ] = v4.z;
									customAttribute.array[ offset_custom + 15 ] = v4.w;

									customAttribute.offset += 16;

								}

							}

						}

					}

				}


				if ( dirtyMorphTargets ) {

					for ( vk = 0, vkl = morphTargets.length; vk < vkl; vk ++ ) {

						v1 = morphTargets[ vk ].vertices[ face.a ].position;
						v2 = morphTargets[ vk ].vertices[ face.b ].position;
						v3 = morphTargets[ vk ].vertices[ face.c ].position;
						v4 = morphTargets[ vk ].vertices[ face.d ].position;

						vka = morphTargetsArrays[ vk ];

						vka[ offset_morphTarget ] 	  = v1.x;
						vka[ offset_morphTarget + 1 ] = v1.y;
						vka[ offset_morphTarget + 2 ] = v1.z;

						vka[ offset_morphTarget + 3 ] = v2.x;
						vka[ offset_morphTarget + 4 ] = v2.y;
						vka[ offset_morphTarget + 5 ] = v2.z;

						vka[ offset_morphTarget + 6 ] = v3.x;
						vka[ offset_morphTarget + 7 ] = v3.y;
						vka[ offset_morphTarget + 8 ] = v3.z;

						vka[ offset_morphTarget + 9 ]  = v4.x;
						vka[ offset_morphTarget + 10 ] = v4.y;
						vka[ offset_morphTarget + 11 ] = v4.z;

					}

					offset_morphTarget += 12;

				}

				if ( obj_skinWeights.length ) {

					// weights

					sw1 = obj_skinWeights[ face.a ];
					sw2 = obj_skinWeights[ face.b ];
					sw3 = obj_skinWeights[ face.c ];
					sw4 = obj_skinWeights[ face.d ];

					skinWeightArray[ offset_skin ]     = sw1.x;
					skinWeightArray[ offset_skin + 1 ] = sw1.y;
					skinWeightArray[ offset_skin + 2 ] = sw1.z;
					skinWeightArray[ offset_skin + 3 ] = sw1.w;

					skinWeightArray[ offset_skin + 4 ] = sw2.x;
					skinWeightArray[ offset_skin + 5 ] = sw2.y;
					skinWeightArray[ offset_skin + 6 ] = sw2.z;
					skinWeightArray[ offset_skin + 7 ] = sw2.w;

					skinWeightArray[ offset_skin + 8 ]  = sw3.x;
					skinWeightArray[ offset_skin + 9 ]  = sw3.y;
					skinWeightArray[ offset_skin + 10 ] = sw3.z;
					skinWeightArray[ offset_skin + 11 ] = sw3.w;

					skinWeightArray[ offset_skin + 12 ] = sw4.x;
					skinWeightArray[ offset_skin + 13 ] = sw4.y;
					skinWeightArray[ offset_skin + 14 ] = sw4.z;
					skinWeightArray[ offset_skin + 15 ] = sw4.w;

					// indices

					si1 = obj_skinIndices[ face.a ];
					si2 = obj_skinIndices[ face.b ];
					si3 = obj_skinIndices[ face.c ];
					si4 = obj_skinIndices[ face.d ];

					skinIndexArray[ offset_skin ]     = si1.x;
					skinIndexArray[ offset_skin + 1 ] = si1.y;
					skinIndexArray[ offset_skin + 2 ] = si1.z;
					skinIndexArray[ offset_skin + 3 ] = si1.w;

					skinIndexArray[ offset_skin + 4 ] = si2.x;
					skinIndexArray[ offset_skin + 5 ] = si2.y;
					skinIndexArray[ offset_skin + 6 ] = si2.z;
					skinIndexArray[ offset_skin + 7 ] = si2.w;

					skinIndexArray[ offset_skin + 8 ]  = si3.x;
					skinIndexArray[ offset_skin + 9 ]  = si3.y;
					skinIndexArray[ offset_skin + 10 ] = si3.z;
					skinIndexArray[ offset_skin + 11 ] = si3.w;

					skinIndexArray[ offset_skin + 12 ] = si4.x;
					skinIndexArray[ offset_skin + 13 ] = si4.y;
					skinIndexArray[ offset_skin + 14 ] = si4.z;
					skinIndexArray[ offset_skin + 15 ] = si4.w;

					// vertices A

					sa1 = obj_skinVerticesA[ face.a ];
					sa2 = obj_skinVerticesA[ face.b ];
					sa3 = obj_skinVerticesA[ face.c ];
					sa4 = obj_skinVerticesA[ face.d ];

					skinVertexAArray[ offset_skin ]     = sa1.x;
					skinVertexAArray[ offset_skin + 1 ] = sa1.y;
					skinVertexAArray[ offset_skin + 2 ] = sa1.z;
					skinVertexAArray[ offset_skin + 3 ] = 1; // pad for faster vertex shader

					skinVertexAArray[ offset_skin + 4 ] = sa2.x;
					skinVertexAArray[ offset_skin + 5 ] = sa2.y;
					skinVertexAArray[ offset_skin + 6 ] = sa2.z;
					skinVertexAArray[ offset_skin + 7 ] = 1;

					skinVertexAArray[ offset_skin + 8 ]  = sa3.x;
					skinVertexAArray[ offset_skin + 9 ]  = sa3.y;
					skinVertexAArray[ offset_skin + 10 ] = sa3.z;
					skinVertexAArray[ offset_skin + 11 ] = 1;

					skinVertexAArray[ offset_skin + 12 ] = sa4.x;
					skinVertexAArray[ offset_skin + 13 ] = sa4.y;
					skinVertexAArray[ offset_skin + 14 ] = sa4.z;
					skinVertexAArray[ offset_skin + 15 ] = 1;

					// vertices B

					sb1 = obj_skinVerticesB[ face.a ];
					sb2 = obj_skinVerticesB[ face.b ];
					sb3 = obj_skinVerticesB[ face.c ];
					sb4 = obj_skinVerticesB[ face.d ];

					skinVertexBArray[ offset_skin ]     = sb1.x;
					skinVertexBArray[ offset_skin + 1 ] = sb1.y;
					skinVertexBArray[ offset_skin + 2 ] = sb1.z;
					skinVertexBArray[ offset_skin + 3 ] = 1; // pad for faster vertex shader

					skinVertexBArray[ offset_skin + 4 ] = sb2.x;
					skinVertexBArray[ offset_skin + 5 ] = sb2.y;
					skinVertexBArray[ offset_skin + 6 ] = sb2.z;
					skinVertexBArray[ offset_skin + 7 ] = 1;

					skinVertexBArray[ offset_skin + 8 ]  = sb3.x;
					skinVertexBArray[ offset_skin + 9 ]  = sb3.y;
					skinVertexBArray[ offset_skin + 10 ] = sb3.z;
					skinVertexBArray[ offset_skin + 11 ] = 1;

					skinVertexBArray[ offset_skin + 12 ] = sb4.x;
					skinVertexBArray[ offset_skin + 13 ] = sb4.y;
					skinVertexBArray[ offset_skin + 14 ] = sb4.z;
					skinVertexBArray[ offset_skin + 15 ] = 1;

					offset_skin += 16;

				}

				if ( dirtyColors && vertexColorType ) {

					if ( vertexColors.length == 4 && vertexColorType == THREE.VertexColors ) {

						c1 = vertexColors[ 0 ];
						c2 = vertexColors[ 1 ];
						c3 = vertexColors[ 2 ];
						c4 = vertexColors[ 3 ];

					} else {

						c1 = faceColor;
						c2 = faceColor;
						c3 = faceColor;
						c4 = faceColor;

					}

					colorArray[ offset_color ]     = c1.r;
					colorArray[ offset_color + 1 ] = c1.g;
					colorArray[ offset_color + 2 ] = c1.b;

					colorArray[ offset_color + 3 ] = c2.r;
					colorArray[ offset_color + 4 ] = c2.g;
					colorArray[ offset_color + 5 ] = c2.b;

					colorArray[ offset_color + 6 ] = c3.r;
					colorArray[ offset_color + 7 ] = c3.g;
					colorArray[ offset_color + 8 ] = c3.b;

					colorArray[ offset_color + 9 ]  = c4.r;
					colorArray[ offset_color + 10 ] = c4.g;
					colorArray[ offset_color + 11 ] = c4.b;

					offset_color += 12;

				}

				if ( dirtyTangents && geometry.hasTangents ) {

					t1 = vertexTangents[ 0 ];
					t2 = vertexTangents[ 1 ];
					t3 = vertexTangents[ 2 ];
					t4 = vertexTangents[ 3 ];

					tangentArray[ offset_tangent ]     = t1.x;
					tangentArray[ offset_tangent + 1 ] = t1.y;
					tangentArray[ offset_tangent + 2 ] = t1.z;
					tangentArray[ offset_tangent + 3 ] = t1.w;

					tangentArray[ offset_tangent + 4 ] = t2.x;
					tangentArray[ offset_tangent + 5 ] = t2.y;
					tangentArray[ offset_tangent + 6 ] = t2.z;
					tangentArray[ offset_tangent + 7 ] = t2.w;

					tangentArray[ offset_tangent + 8 ]  = t3.x;
					tangentArray[ offset_tangent + 9 ]  = t3.y;
					tangentArray[ offset_tangent + 10 ] = t3.z;
					tangentArray[ offset_tangent + 11 ] = t3.w;

					tangentArray[ offset_tangent + 12 ] = t4.x;
					tangentArray[ offset_tangent + 13 ] = t4.y;
					tangentArray[ offset_tangent + 14 ] = t4.z;
					tangentArray[ offset_tangent + 15 ] = t4.w;

					offset_tangent += 16;

				}

				if ( dirtyNormals && normalType ) {

					if ( vertexNormals.length == 4 && needsSmoothNormals ) {

						for ( i = 0; i < 4; i ++ ) {

							vn = vertexNormals[ i ];

							normalArray[ offset_normal ]     = vn.x;
							normalArray[ offset_normal + 1 ] = vn.y;
							normalArray[ offset_normal + 2 ] = vn.z;

							offset_normal += 3;

						}

					} else {

						for ( i = 0; i < 4; i ++ ) {

							normalArray[ offset_normal ]     = faceNormal.x;
							normalArray[ offset_normal + 1 ] = faceNormal.y;
							normalArray[ offset_normal + 2 ] = faceNormal.z;

							offset_normal += 3;

						}

					}

				}

				if ( dirtyUvs && uv !== undefined && uvType ) {

					for ( i = 0; i < 4; i ++ ) {

						uvi = uv[ i ];

						uvArray[ offset_uv ]     = uvi.u;
						uvArray[ offset_uv + 1 ] = uvi.v;

						offset_uv += 2;

					}

				}

				if ( dirtyUvs && uv2 !== undefined && uvType ) {

					for ( i = 0; i < 4; i ++ ) {

						uv2i = uv2[ i ];

						uv2Array[ offset_uv2 ]     = uv2i.u;
						uv2Array[ offset_uv2 + 1 ] = uv2i.v;

						offset_uv2 += 2;

					}

				}

				if ( dirtyElements ) {

					faceArray[ offset_face ]     = vertexIndex;
					faceArray[ offset_face + 1 ] = vertexIndex + 1;
					faceArray[ offset_face + 2 ] = vertexIndex + 3;

					faceArray[ offset_face + 3 ] = vertexIndex + 1;
					faceArray[ offset_face + 4 ] = vertexIndex + 2;
					faceArray[ offset_face + 5 ] = vertexIndex + 3;

					offset_face += 6;

					lineArray[ offset_line ]     = vertexIndex;
					lineArray[ offset_line + 1 ] = vertexIndex + 1;

					lineArray[ offset_line + 2 ] = vertexIndex;
					lineArray[ offset_line + 3 ] = vertexIndex + 3;

					lineArray[ offset_line + 4 ] = vertexIndex + 1;
					lineArray[ offset_line + 5 ] = vertexIndex + 2;

					lineArray[ offset_line + 6 ] = vertexIndex + 2;
					lineArray[ offset_line + 7 ] = vertexIndex + 3;

					offset_line += 8;

					vertexIndex += 4;

				}

			}

		}

		if ( dirtyVertices ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglVertexBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, vertexArray, hint );

		}

		if ( customAttributes ) {

			for ( a in customAttributes ) {

				customAttribute = customAttributes[ a ];

				if ( customAttribute.__original.needsUpdate ) {

					_gl.bindBuffer( _gl.ARRAY_BUFFER, customAttribute.buffer );
					_gl.bufferData( _gl.ARRAY_BUFFER, customAttribute.array, hint );

				}

			}

		}

		if ( dirtyMorphTargets ) {

			for ( vk = 0, vkl = morphTargets.length; vk < vkl; vk ++ ) {

				_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglMorphTargetsBuffers[ vk ] );
				_gl.bufferData( _gl.ARRAY_BUFFER, morphTargetsArrays[ vk ], hint );

			}

		}

		if ( dirtyColors && offset_color > 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglColorBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, colorArray, hint );

		}

		if ( dirtyNormals ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglNormalBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, normalArray, hint );

		}

		if ( dirtyTangents && geometry.hasTangents ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglTangentBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, tangentArray, hint );

		}

		if ( dirtyUvs && offset_uv > 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglUVBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, uvArray, hint );

		}

		if ( dirtyUvs && offset_uv2 > 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglUV2Buffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, uv2Array, hint );

		}

		if ( dirtyElements ) {

			_gl.bindBuffer( _gl.ELEMENT_ARRAY_BUFFER, geometryGroup.__webglFaceBuffer );
			_gl.bufferData( _gl.ELEMENT_ARRAY_BUFFER, faceArray, hint );

			_gl.bindBuffer( _gl.ELEMENT_ARRAY_BUFFER, geometryGroup.__webglLineBuffer );
			_gl.bufferData( _gl.ELEMENT_ARRAY_BUFFER, lineArray, hint );

		}

		if ( offset_skin > 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglSkinVertexABuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, skinVertexAArray, hint );

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglSkinVertexBBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, skinVertexBArray, hint );

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglSkinIndicesBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, skinIndexArray, hint );

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglSkinWeightsBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, skinWeightArray, hint );

		}

		if ( dispose ) {

			delete geometryGroup.__inittedArrays;
			delete geometryGroup.__colorArray;
			delete geometryGroup.__normalArray;
			delete geometryGroup.__tangentArray;
			delete geometryGroup.__uvArray;
			delete geometryGroup.__uv2Array;
			delete geometryGroup.__faceArray;
			delete geometryGroup.__vertexArray;
			delete geometryGroup.__lineArray;
			delete geometryGroup.__skinVertexAArray;
			delete geometryGroup.__skinVertexBArray;
			delete geometryGroup.__skinIndexArray;
			delete geometryGroup.__skinWeightArray;

		}

	};

	function setLineBuffers ( geometry, hint ) {

		var v, c, vertex, offset,
		vertices = geometry.vertices,
		colors = geometry.colors,
		vl = vertices.length,
		cl = colors.length,

		vertexArray = geometry.__vertexArray,
		colorArray = geometry.__colorArray,

		dirtyVertices = geometry.__dirtyVertices,
		dirtyColors = geometry.__dirtyColors;

		if ( dirtyVertices ) {

			for ( v = 0; v < vl; v ++ ) {

				vertex = vertices[ v ].position;

				offset = v * 3;

				vertexArray[ offset ]     = vertex.x;
				vertexArray[ offset + 1 ] = vertex.y;
				vertexArray[ offset + 2 ] = vertex.z;

			}

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometry.__webglVertexBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, vertexArray, hint );

		}

		if ( dirtyColors ) {

			for ( c = 0; c < cl; c ++ ) {

				color = colors[ c ];

				offset = c * 3;

				colorArray[ offset ]     = color.r;
				colorArray[ offset + 1 ] = color.g;
				colorArray[ offset + 2 ] = color.b;

			}

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometry.__webglColorBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, colorArray, hint );

		}

	};

	function setRibbonBuffers ( geometry, hint ) {

		var v, c, vertex, offset,
		vertices = geometry.vertices,
		colors = geometry.colors,
		vl = vertices.length,
		cl = colors.length,

		vertexArray = geometry.__vertexArray,
		colorArray = geometry.__colorArray,

		dirtyVertices = geometry.__dirtyVertices,
		dirtyColors = geometry.__dirtyColors;

		if ( dirtyVertices ) {

			for ( v = 0; v < vl; v ++ ) {

				vertex = vertices[ v ].position;

				offset = v * 3;

				vertexArray[ offset ]     = vertex.x;
				vertexArray[ offset + 1 ] = vertex.y;
				vertexArray[ offset + 2 ] = vertex.z;

			}

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometry.__webglVertexBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, vertexArray, hint );

		}

		if ( dirtyColors ) {

			for ( c = 0; c < cl; c ++ ) {

				color = colors[ c ];

				offset = c * 3;

				colorArray[ offset ]     = color.r;
				colorArray[ offset + 1 ] = color.g;
				colorArray[ offset + 2 ] = color.b;

			}

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometry.__webglColorBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, colorArray, hint );

		}

	};

	function setParticleBuffers ( geometry, hint, object ) {

		var v, c, vertex, offset,
		vertices = geometry.vertices,
		vl = vertices.length,

		colors = geometry.colors,
		cl = colors.length,

		vertexArray = geometry.__vertexArray,
		colorArray = geometry.__colorArray,

		sortArray = geometry.__sortArray,

		dirtyVertices = geometry.__dirtyVertices,
		dirtyElements = geometry.__dirtyElements,
		dirtyColors = geometry.__dirtyColors,

		customAttributes = geometry.__webglCustomAttributes,
		a, ca, cal, v1,
		offset_custom,
		customAttribute;

		if ( customAttributes ) {

			for ( a in customAttributes ) {

				customAttributes[ a ].offset = 0;

			}

		}

		if ( object.sortParticles ) {

			_projScreenMatrix.multiplySelf( object.matrixWorld );

			for ( v = 0; v < vl; v++ ) {

				vertex = vertices[ v ].position;

				_vector3.copy( vertex );
				_projScreenMatrix.multiplyVector3( _vector3 );

				sortArray[ v ] = [ _vector3.z, v ];

			}

			sortArray.sort( function( a, b ) { return b[ 0 ] - a[ 0 ]; } );

			for ( v = 0; v < vl; v++ ) {

				vertex = vertices[ sortArray[v][1] ].position;

				offset = v * 3;

				vertexArray[ offset ]     = vertex.x;
				vertexArray[ offset + 1 ] = vertex.y;
				vertexArray[ offset + 2 ] = vertex.z;

			}

			for ( c = 0; c < cl; c ++ ) {

				offset = c * 3;

				color = colors[ sortArray[c][1] ];

				colorArray[ offset ]     = color.r;
				colorArray[ offset + 1 ] = color.g;
				colorArray[ offset + 2 ] = color.b;

			}

			if ( customAttributes ) {

				for ( a in customAttributes ) {

					customAttribute = customAttributes[ a ];

					cal = customAttribute.value.length;

					for ( ca = 0; ca < cal; ca ++ ) {

						index = sortArray[ca][1];

						offset_custom = customAttribute.offset;

						if ( customAttribute.size === 1 ) {

							if ( customAttribute.boundTo === undefined || customAttribute.boundTo === "vertices" ) {

								customAttribute.array[ offset_custom ] = customAttribute.value[ index ];

							}

						} else {

							if ( customAttribute.boundTo === undefined || customAttribute.boundTo === "vertices" ) {

								v1 = customAttribute.value[ index ];

							}

							if ( customAttribute.size === 2 ) {

								customAttribute.array[ offset_custom ] 	   = v1.x;
								customAttribute.array[ offset_custom + 1 ] = v1.y;

							} else if ( customAttribute.size === 3 ) {

								if ( customAttribute.type === "c" ) {

									customAttribute.array[ offset_custom ] 	   = v1.r;
									customAttribute.array[ offset_custom + 1 ] = v1.g;
									customAttribute.array[ offset_custom + 2 ] = v1.b;

								} else {

									customAttribute.array[ offset_custom ] 	   = v1.x;
									customAttribute.array[ offset_custom + 1 ] = v1.y;
									customAttribute.array[ offset_custom + 2 ] = v1.z;

								}

							} else {

								customAttribute.array[ offset_custom ] 		= v1.x;
								customAttribute.array[ offset_custom + 1  ] = v1.y;
								customAttribute.array[ offset_custom + 2  ] = v1.z;
								customAttribute.array[ offset_custom + 3  ] = v1.w;

							}

						}

						customAttribute.offset += customAttribute.size;

					}

				}

			}


		} else {

			if ( dirtyVertices ) {

				for ( v = 0; v < vl; v++ ) {

					vertex = vertices[ v ].position;

					offset = v * 3;

					vertexArray[ offset ]     = vertex.x;
					vertexArray[ offset + 1 ] = vertex.y;
					vertexArray[ offset + 2 ] = vertex.z;

				}

			}

			if ( dirtyColors ) {

				for ( c = 0; c < cl; c ++ ) {

					color = colors[ c ];

					offset = c * 3;

					colorArray[ offset ]     = color.r;
					colorArray[ offset + 1 ] = color.g;
					colorArray[ offset + 2 ] = color.b;

				}

			}

			if ( customAttributes ) {

				for ( a in customAttributes ) {

					customAttribute = customAttributes[ a ];

					if ( customAttribute.__original.needsUpdate ) {

						cal = customAttribute.value.length;

						for ( ca = 0; ca < cal; ca ++ ) {

							offset_custom = customAttribute.offset;

							if ( customAttribute.size === 1 ) {

								if ( customAttribute.boundTo === undefined || customAttribute.boundTo === "vertices" ) {

									customAttribute.array[ offset_custom ] = customAttribute.value[ ca ];

								}

							} else {

								if ( customAttribute.boundTo === undefined || customAttribute.boundTo === "vertices" ) {

									v1 = customAttribute.value[ ca ];

								}

								if ( customAttribute.size === 2 ) {

									customAttribute.array[ offset_custom ] 	   = v1.x;
									customAttribute.array[ offset_custom + 1 ] = v1.y;

								} else if ( customAttribute.size === 3 ) {

									if ( customAttribute.type === "c" ) {

										customAttribute.array[ offset_custom ] 	   = v1.r;
										customAttribute.array[ offset_custom + 1 ] = v1.g;
										customAttribute.array[ offset_custom + 2 ] = v1.b;


									} else {

										customAttribute.array[ offset_custom ] 	   = v1.x;
										customAttribute.array[ offset_custom + 1 ] = v1.y;
										customAttribute.array[ offset_custom + 2 ] = v1.z;

									}

								} else {

									customAttribute.array[ offset_custom ] 		= v1.x;
									customAttribute.array[ offset_custom + 1  ] = v1.y;
									customAttribute.array[ offset_custom + 2  ] = v1.z;
									customAttribute.array[ offset_custom + 3  ] = v1.w;

								}

							}

							customAttribute.offset += customAttribute.size;

						}

					}

				}

			}

		}

		if ( dirtyVertices || object.sortParticles ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometry.__webglVertexBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, vertexArray, hint );

		}

		if ( dirtyColors || object.sortParticles ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometry.__webglColorBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, colorArray, hint );

		}

		if ( customAttributes ) {

			for ( a in customAttributes ) {

				customAttribute = customAttributes[ a ];

				if ( customAttribute.__original.needsUpdate || object.sortParticles ) {

					_gl.bindBuffer( _gl.ARRAY_BUFFER, customAttribute.buffer );
					_gl.bufferData( _gl.ARRAY_BUFFER, customAttribute.array, hint );

				}

			}

		}


	};

	function setMaterialShaders( material, shaders ) {

		material.uniforms = THREE.UniformsUtils.clone( shaders.uniforms );
		material.vertexShader = shaders.vertexShader;
		material.fragmentShader = shaders.fragmentShader;

	};

	function refreshUniformsCommon( uniforms, material ) {

		uniforms.diffuse.value = material.color;
		uniforms.opacity.value = material.opacity;

		uniforms.map.texture = material.map;
		if ( material.map ) {

			uniforms.offsetRepeat.value.set( material.map.offset.x, material.map.offset.y, material.map.repeat.x, material.map.repeat.y );

		}

		uniforms.lightMap.texture = material.lightMap;

		uniforms.envMap.texture = material.envMap;
		uniforms.reflectivity.value = material.reflectivity;
		uniforms.refractionRatio.value = material.refractionRatio;
		uniforms.combine.value = material.combine;
		uniforms.useRefract.value = material.envMap && material.envMap.mapping instanceof THREE.CubeRefractionMapping;

	};

	function refreshUniformsLine( uniforms, material ) {

		uniforms.diffuse.value = material.color;
		uniforms.opacity.value = material.opacity;

	};

	function refreshUniformsParticle( uniforms, material ) {

		uniforms.psColor.value = material.color;
		uniforms.opacity.value = material.opacity;
		uniforms.size.value = material.size;
		uniforms.scale.value = _canvas.height / 2.0; // TODO: Cache this.

		uniforms.map.texture = material.map;

	};

	function refreshUniformsFog( uniforms, fog ) {

		uniforms.fogColor.value = fog.color;

		if ( fog instanceof THREE.Fog ) {

			uniforms.fogNear.value = fog.near;
			uniforms.fogFar.value = fog.far;

		} else if ( fog instanceof THREE.FogExp2 ) {

			uniforms.fogDensity.value = fog.density;

		}

	};

	function refreshUniformsPhong( uniforms, material ) {

		uniforms.ambient.value = material.ambient;
		uniforms.specular.value = material.specular;
		uniforms.shininess.value = material.shininess;

	};


	function refreshUniformsLights( uniforms, lights ) {

		uniforms.enableLighting.value = lights.directional.length + lights.point.length;
		uniforms.ambientLightColor.value = lights.ambient;

		uniforms.directionalLightColor.value = lights.directional.colors;
		uniforms.directionalLightDirection.value = lights.directional.positions;

		uniforms.pointLightColor.value = lights.point.colors;
		uniforms.pointLightPosition.value = lights.point.positions;
		uniforms.pointLightDistance.value = lights.point.distances;

	};

	function refreshUniformsShadow( uniforms, material ) {

		if ( uniforms.shadowMatrix ) {

			for ( var i = 0; i < _shadowMatrix.length; i ++ ) {

				uniforms.shadowMatrix.value[ i ] = _shadowMatrix[ i ];
				uniforms.shadowMap.texture[ i ] = _this.shadowMap[ i ];


			}

			uniforms.shadowDarkness.value = _this.shadowMapDarkness;
			uniforms.shadowBias.value = _this.shadowMapBias;

		}

	};

	this.initMaterial = function ( material, lights, fog, object ) {

		var u, a, identifiers, i, parameters, maxLightCount, maxBones, maxShadows, shaderID;

		if ( material instanceof THREE.MeshDepthMaterial ) {

			shaderID = 'depth';

		} else if ( material instanceof THREE.MeshNormalMaterial ) {

			shaderID = 'normal';

		} else if ( material instanceof THREE.MeshBasicMaterial ) {

			shaderID = 'basic';

		} else if ( material instanceof THREE.MeshLambertMaterial ) {

			shaderID = 'lambert';

		} else if ( material instanceof THREE.MeshPhongMaterial ) {

			shaderID = 'phong';

		} else if ( material instanceof THREE.LineBasicMaterial ) {

			shaderID = 'basic';

		} else if ( material instanceof THREE.ParticleBasicMaterial ) {

			shaderID = 'particle_basic';

		}

		if ( shaderID ) {

			setMaterialShaders( material, THREE.ShaderLib[ shaderID ] );

		}

		// heuristics to create shader parameters according to lights in the scene
		// (not to blow over maxLights budget)

		maxLightCount = allocateLights( lights, 4 );

		maxShadows = allocateShadows( lights );

		maxBones = allocateBones( object );

		parameters = {

			map: !!material.map, envMap: !!material.envMap, lightMap: !!material.lightMap,
			vertexColors: material.vertexColors,
			fog: fog, sizeAttenuation: material.sizeAttenuation,
			skinning: material.skinning,
			morphTargets: material.morphTargets,
			maxMorphTargets: this.maxMorphTargets,
			maxDirLights: maxLightCount.directional, maxPointLights: maxLightCount.point,
			maxBones: maxBones,
			shadowMapEnabled: this.shadowMapEnabled && object.receiveShadow,
			shadowMapSoft: this.shadowMapSoft,
			shadowMapWidth: this.shadowMapWidth,
			shadowMapHeight: this.shadowMapHeight,
			maxShadows: maxShadows,
			alphaTest: material.alphaTest

		};

		material.program = buildProgram( shaderID, material.fragmentShader, material.vertexShader, material.uniforms, material.attributes, parameters );

		var attributes = material.program.attributes;

		if ( attributes.position >= 0 ) _gl.enableVertexAttribArray( attributes.position );
		if ( attributes.color >= 0 ) _gl.enableVertexAttribArray( attributes.color );
		if ( attributes.normal >= 0 ) _gl.enableVertexAttribArray( attributes.normal );
		if ( attributes.tangent >= 0 ) _gl.enableVertexAttribArray( attributes.tangent );

		if ( material.skinning &&
			 attributes.skinVertexA >=0 && attributes.skinVertexB >= 0 &&
			 attributes.skinIndex >= 0 && attributes.skinWeight >= 0 ) {

			_gl.enableVertexAttribArray( attributes.skinVertexA );
			_gl.enableVertexAttribArray( attributes.skinVertexB );
			_gl.enableVertexAttribArray( attributes.skinIndex );
			_gl.enableVertexAttribArray( attributes.skinWeight );

		}

		if ( material.attributes ) {

			for ( a in material.attributes ) {

				if( attributes[ a ] !== undefined && attributes[ a ] >= 0 ) _gl.enableVertexAttribArray( attributes[ a ] );

			}

		}

		if ( material.morphTargets ) {

			material.numSupportedMorphTargets = 0;

			var id, base = "morphTarget";

			for ( i = 0; i < this.maxMorphTargets; i ++ ) {

				id = base + i;

				if ( attributes[ id ] >= 0 ) {

					_gl.enableVertexAttribArray( attributes[ id ] );
					material.numSupportedMorphTargets ++;

				}

			}

		}

	};

	function setProgram( camera, lights, fog, material, object ) {

		if ( ! material.program ) {

			_this.initMaterial( material, lights, fog, object );

		}

		if ( material.morphTargets ) {

			if ( ! object.__webglMorphTargetInfluences ) {

				object.__webglMorphTargetInfluences = new Float32Array( _this.maxMorphTargets );

				for ( var i = 0, il = _this.maxMorphTargets; i < il; i ++ ) {

					object.__webglMorphTargetInfluences[ i ] = 0;

				}

			}

		}

		var program = material.program,
			p_uniforms = program.uniforms,
			m_uniforms = material.uniforms;

		if ( program != _currentProgram ) {

			_gl.useProgram( program );
			_currentProgram = program;

		}

		_gl.uniformMatrix4fv( p_uniforms.projectionMatrix, false, _projectionMatrixArray );

		// refresh uniforms common to several materials

		if ( fog && (
			 material instanceof THREE.MeshBasicMaterial ||
			 material instanceof THREE.MeshLambertMaterial ||
			 material instanceof THREE.MeshPhongMaterial ||
			 material instanceof THREE.LineBasicMaterial ||
			 material instanceof THREE.ParticleBasicMaterial ||
			 material.fog )
			) {

			refreshUniformsFog( m_uniforms, fog );

		}

		if ( material instanceof THREE.MeshPhongMaterial ||
			 material instanceof THREE.MeshLambertMaterial ||
			 material.lights ) {

			setupLights( program, lights );
			refreshUniformsLights( m_uniforms, _lights );

		}

		if ( material instanceof THREE.MeshBasicMaterial ||
			 material instanceof THREE.MeshLambertMaterial ||
			 material instanceof THREE.MeshPhongMaterial ) {

			refreshUniformsCommon( m_uniforms, material );

		}

		// refresh single material specific uniforms

		if ( material instanceof THREE.LineBasicMaterial ) {

			refreshUniformsLine( m_uniforms, material );

		} else if ( material instanceof THREE.ParticleBasicMaterial ) {

			refreshUniformsParticle( m_uniforms, material );

		} else if ( material instanceof THREE.MeshPhongMaterial ) {

			refreshUniformsPhong( m_uniforms, material );

		} else if ( material instanceof THREE.MeshDepthMaterial ) {

			m_uniforms.mNear.value = camera.near;
			m_uniforms.mFar.value = camera.far;
			m_uniforms.opacity.value = material.opacity;

		} else if ( material instanceof THREE.MeshNormalMaterial ) {

			m_uniforms.opacity.value = material.opacity;

		}

		if ( object.receiveShadow && ! material._shadowPass ) {

			refreshUniformsShadow( m_uniforms, material );

		}

		// load common uniforms

		loadUniformsGeneric( program, m_uniforms );
		loadUniformsMatrices( p_uniforms, object );

		// load material specific uniforms
		// (shader material also gets them for the sake of genericity)

		if ( material instanceof THREE.MeshShaderMaterial ||
			 material instanceof THREE.MeshPhongMaterial ||
			 material.envMap ) {

			if( p_uniforms.cameraPosition !== null ) {

				_gl.uniform3f( p_uniforms.cameraPosition, camera.position.x, camera.position.y, camera.position.z );

			}

		}

		if ( material instanceof THREE.MeshShaderMaterial ||
			 material.envMap ||
			 material.skinning ||
			 object.receiveShadow ) {

			if ( p_uniforms.objectMatrix !== null ) {

				_gl.uniformMatrix4fv( p_uniforms.objectMatrix, false, object._objectMatrixArray );

			}

		}

		if ( material instanceof THREE.MeshPhongMaterial ||
			 material instanceof THREE.MeshLambertMaterial ||
			 material instanceof THREE.MeshShaderMaterial ||
			 material.skinning ) {

			if( p_uniforms.viewMatrix !== null ) {

				_gl.uniformMatrix4fv( p_uniforms.viewMatrix, false, _viewMatrixArray );

			}

		}

		if ( material.skinning ) {

			loadUniformsSkinning( p_uniforms, object );

		}

		return program;

	};

	function renderBuffer( camera, lights, fog, material, geometryGroup, object ) {

		if ( material.opacity == 0 ) return;

		var program, attributes, linewidth, primitives, a, attribute;

		program = setProgram( camera, lights, fog, material, object );

		attributes = program.attributes;

		// vertices

		if ( !material.morphTargets && attributes.position >= 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglVertexBuffer );
			_gl.vertexAttribPointer( attributes.position, 3, _gl.FLOAT, false, 0, 0 );

		} else {

			if ( object.morphTargetBase ) {

				setupMorphTargets( material, geometryGroup, object );

			}

		}


		// custom attributes

		// Use the per-geometryGroup custom attribute arrays which are setup in initMeshBuffers

		if ( geometryGroup.__webglCustomAttributes ) {

			for( a in geometryGroup.__webglCustomAttributes ) {

				if( attributes[ a ] >= 0 ) {

					attribute = geometryGroup.__webglCustomAttributes[ a ];

					_gl.bindBuffer( _gl.ARRAY_BUFFER, attribute.buffer );
					_gl.vertexAttribPointer( attributes[ a ], attribute.size, _gl.FLOAT, false, 0, 0 );

				}

			}

		}


/*		if ( material.attributes ) {

			for( a in material.attributes ) {

				if( attributes[ a ] !== undefined && attributes[ a ] >= 0 ) {

					attribute = material.attributes[ a ];

					if( attribute.buffer ) {

						_gl.bindBuffer( _gl.ARRAY_BUFFER, attribute.buffer );
						_gl.vertexAttribPointer( attributes[ a ], attribute.size, _gl.FLOAT, false, 0, 0 );

					}

				}

			}

		}*/



		// colors

		if ( attributes.color >= 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglColorBuffer );
			_gl.vertexAttribPointer( attributes.color, 3, _gl.FLOAT, false, 0, 0 );

		}

		// normals

		if ( attributes.normal >= 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglNormalBuffer );
			_gl.vertexAttribPointer( attributes.normal, 3, _gl.FLOAT, false, 0, 0 );

		}

		// tangents

		if ( attributes.tangent >= 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglTangentBuffer );
			_gl.vertexAttribPointer( attributes.tangent, 4, _gl.FLOAT, false, 0, 0 );

		}

		// uvs

		if ( attributes.uv >= 0 ) {

			if ( geometryGroup.__webglUVBuffer ) {

				_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglUVBuffer );
				_gl.vertexAttribPointer( attributes.uv, 2, _gl.FLOAT, false, 0, 0 );

				_gl.enableVertexAttribArray( attributes.uv );

			} else {

				_gl.disableVertexAttribArray( attributes.uv );

			}

		}

		if ( attributes.uv2 >= 0 ) {

			if ( geometryGroup.__webglUV2Buffer ) {

				_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglUV2Buffer );
				_gl.vertexAttribPointer( attributes.uv2, 2, _gl.FLOAT, false, 0, 0 );

				_gl.enableVertexAttribArray( attributes.uv2 );

			} else {

				_gl.disableVertexAttribArray( attributes.uv2 );

			}

		}

		if ( material.skinning &&
			 attributes.skinVertexA >= 0 && attributes.skinVertexB >= 0 &&
			 attributes.skinIndex >= 0 && attributes.skinWeight >= 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglSkinVertexABuffer );
			_gl.vertexAttribPointer( attributes.skinVertexA, 4, _gl.FLOAT, false, 0, 0 );

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglSkinVertexBBuffer );
			_gl.vertexAttribPointer( attributes.skinVertexB, 4, _gl.FLOAT, false, 0, 0 );

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglSkinIndicesBuffer );
			_gl.vertexAttribPointer( attributes.skinIndex, 4, _gl.FLOAT, false, 0, 0 );

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglSkinWeightsBuffer );
			_gl.vertexAttribPointer( attributes.skinWeight, 4, _gl.FLOAT, false, 0, 0 );

		}

		// render mesh

		if ( object instanceof THREE.Mesh ) {

			// wireframe

			if ( material.wireframe ) {

				_gl.lineWidth( material.wireframeLinewidth );
				_gl.bindBuffer( _gl.ELEMENT_ARRAY_BUFFER, geometryGroup.__webglLineBuffer );
				_gl.drawElements( _gl.LINES, geometryGroup.__webglLineCount, _gl.UNSIGNED_SHORT, 0 );

			// triangles

			} else {

				_gl.bindBuffer( _gl.ELEMENT_ARRAY_BUFFER, geometryGroup.__webglFaceBuffer );
				_gl.drawElements( _gl.TRIANGLES, geometryGroup.__webglFaceCount, _gl.UNSIGNED_SHORT, 0 );

			}

			_this.data.vertices += geometryGroup.__webglFaceCount;
			_this.data.faces += geometryGroup.__webglFaceCount / 3;
			_this.data.drawCalls ++;

		// render lines

		} else if ( object instanceof THREE.Line ) {

			primitives = ( object.type == THREE.LineStrip ) ? _gl.LINE_STRIP : _gl.LINES;

			_gl.lineWidth( material.linewidth );
			_gl.drawArrays( primitives, 0, geometryGroup.__webglLineCount );

			_this.data.drawCalls ++;

		// render particles

		} else if ( object instanceof THREE.ParticleSystem ) {

			_gl.drawArrays( _gl.POINTS, 0, geometryGroup.__webglParticleCount );

			_this.data.drawCalls ++;

		// render ribbon

		} else if ( object instanceof THREE.Ribbon ) {

			_gl.drawArrays( _gl.TRIANGLE_STRIP, 0, geometryGroup.__webglVertexCount );

			_this.data.drawCalls ++;

		}

	};


	function setupMorphTargets( material, geometryGroup, object ) {

		// set base

		var attributes = material.program.attributes;

		if ( object.morphTargetBase !== - 1 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglMorphTargetsBuffers[ object.morphTargetBase ] );
			_gl.vertexAttribPointer( attributes.position, 3, _gl.FLOAT, false, 0, 0 );

		} else if ( attributes.position >= 0 ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglVertexBuffer );
			_gl.vertexAttribPointer( attributes.position, 3, _gl.FLOAT, false, 0, 0 );

		}

		if ( object.morphTargetForcedOrder.length ) {

			// set forced order

			var m = 0;
			var order = object.morphTargetForcedOrder;
			var influences = object.morphTargetInfluences;

			while ( m < material.numSupportedMorphTargets && m < order.length ) {

				_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglMorphTargetsBuffers[ order[ m ] ] );
				_gl.vertexAttribPointer( attributes[ "morphTarget" + m ], 3, _gl.FLOAT, false, 0, 0 );

				object.__webglMorphTargetInfluences[ m ] = influences[ order[ m ] ];

				m ++;
			}

		} else {

			// find most influencing

			var used = [];
			var candidateInfluence = - 1;
			var candidate = 0;
			var influences = object.morphTargetInfluences;
			var i, il = influences.length;
			var m = 0;

			if ( object.morphTargetBase !== - 1 ) {

				used[ object.morphTargetBase ] = true;

			}

			while ( m < material.numSupportedMorphTargets ) {

				for ( i = 0; i < il; i ++ ) {

					if ( !used[ i ] && influences[ i ] > candidateInfluence ) {

						candidate = i;
						candidateInfluence = influences[ candidate ];

					}

				}

				_gl.bindBuffer( _gl.ARRAY_BUFFER, geometryGroup.__webglMorphTargetsBuffers[ candidate ] );
				_gl.vertexAttribPointer( attributes[ "morphTarget" + m ], 3, _gl.FLOAT, false, 0, 0 );

				object.__webglMorphTargetInfluences[ m ] = candidateInfluence;

				used[ candidate ] = 1;
				candidateInfluence = -1;
				m ++;

			}

		}

		// load updated influences uniform

		if( material.program.uniforms.morphTargetInfluences !== null ) {

			_gl.uniform1fv( material.program.uniforms.morphTargetInfluences, object.__webglMorphTargetInfluences );

		}

	}


	function renderBufferImmediate( object, program, shading ) {

		if ( ! object.__webglVertexBuffer ) object.__webglVertexBuffer = _gl.createBuffer();
		if ( ! object.__webglNormalBuffer ) object.__webglNormalBuffer = _gl.createBuffer();

		if ( object.hasPos ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, object.__webglVertexBuffer );
			_gl.bufferData( _gl.ARRAY_BUFFER, object.positionArray, _gl.DYNAMIC_DRAW );
			_gl.enableVertexAttribArray( program.attributes.position );
			_gl.vertexAttribPointer( program.attributes.position, 3, _gl.FLOAT, false, 0, 0 );

		}

		if ( object.hasNormal ) {

			_gl.bindBuffer( _gl.ARRAY_BUFFER, object.__webglNormalBuffer );

			if ( shading == THREE.FlatShading ) {

				var nx, ny, nz,
					nax, nbx, ncx, nay, nby, ncy, naz, nbz, ncz,
					normalArray,
					i, il = object.count * 3;

				for( i = 0; i < il; i += 9 ) {

					normalArray = object.normalArray;

					nax  = normalArray[ i ];
					nay  = normalArray[ i + 1 ];
					naz  = normalArray[ i + 2 ];

					nbx  = normalArray[ i + 3 ];
					nby  = normalArray[ i + 4 ];
					nbz  = normalArray[ i + 5 ];

					ncx  = normalArray[ i + 6 ];
					ncy  = normalArray[ i + 7 ];
					ncz  = normalArray[ i + 8 ];

					nx = ( nax + nbx + ncx ) / 3;
					ny = ( nay + nby + ncy ) / 3;
					nz = ( naz + nbz + ncz ) / 3;

					normalArray[ i ] 	 = nx;
					normalArray[ i + 1 ] = ny;
					normalArray[ i + 2 ] = nz;

					normalArray[ i + 3 ] = nx;
					normalArray[ i + 4 ] = ny;
					normalArray[ i + 5 ] = nz;

					normalArray[ i + 6 ] = nx;
					normalArray[ i + 7 ] = ny;
					normalArray[ i + 8 ] = nz;

				}

			}

			_gl.bufferData( _gl.ARRAY_BUFFER, object.normalArray, _gl.DYNAMIC_DRAW );
			_gl.enableVertexAttribArray( program.attributes.normal );
			_gl.vertexAttribPointer( program.attributes.normal, 3, _gl.FLOAT, false, 0, 0 );

		}

		_gl.drawArrays( _gl.TRIANGLES, 0, object.count );

		object.count = 0;

	};

	function setObjectFaces( object ) {

		if ( _oldDoubleSided != object.doubleSided ) {

			if( object.doubleSided ) {

				_gl.disable( _gl.CULL_FACE );

			} else {

				_gl.enable( _gl.CULL_FACE );

			}

			_oldDoubleSided = object.doubleSided;

		}

		if ( _oldFlipSided != object.flipSided ) {

			if( object.flipSided ) {

				_gl.frontFace( _gl.CW );

			} else {

				_gl.frontFace( _gl.CCW );

			}

			_oldFlipSided = object.flipSided;

		}

	};

	function setDepthTest( test ) {

		if ( _oldDepth != test ) {

			if( test ) {

				_gl.enable( _gl.DEPTH_TEST );

			} else {

				_gl.disable( _gl.DEPTH_TEST );

			}

			_oldDepth = test;

		}

	};

	function setPolygonOffset ( polygonoffset, factor, units ) {

		if ( _oldPolygonOffset != polygonoffset ) {

			if ( polygonoffset ) {

				_gl.enable( _gl.POLYGON_OFFSET_FILL );

			} else {

				_gl.disable( _gl.POLYGON_OFFSET_FILL );

			}

			_oldPolygonOffset = polygonoffset;

		}

		if ( polygonoffset && ( _oldPolygonOffsetFactor != factor || _oldPolygonOffsetUnits != units ) ) {

			_gl.polygonOffset( factor, units );

			_oldPolygonOffsetFactor = factor;
			_oldPolygonOffsetUnits = units;

		}

	};

	function computeFrustum( m ) {

		_frustum[ 0 ].set( m.n41 - m.n11, m.n42 - m.n12, m.n43 - m.n13, m.n44 - m.n14 );
		_frustum[ 1 ].set( m.n41 + m.n11, m.n42 + m.n12, m.n43 + m.n13, m.n44 + m.n14 );
		_frustum[ 2 ].set( m.n41 + m.n21, m.n42 + m.n22, m.n43 + m.n23, m.n44 + m.n24 );
		_frustum[ 3 ].set( m.n41 - m.n21, m.n42 - m.n22, m.n43 - m.n23, m.n44 - m.n24 );
		_frustum[ 4 ].set( m.n41 - m.n31, m.n42 - m.n32, m.n43 - m.n33, m.n44 - m.n34 );
		_frustum[ 5 ].set( m.n41 + m.n31, m.n42 + m.n32, m.n43 + m.n33, m.n44 + m.n34 );

		var i, plane;

		for ( i = 0; i < 6; i ++ ) {

			plane = _frustum[ i ];
			plane.divideScalar( Math.sqrt( plane.x * plane.x + plane.y * plane.y + plane.z * plane.z ) );

		}

	};

	function isInFrustum( object ) {

		var distance, matrix = object.matrixWorld,
		radius = - object.geometry.boundingSphere.radius * Math.max( object.scale.x, Math.max( object.scale.y, object.scale.z ) );

		for ( var i = 0; i < 6; i ++ ) {

			distance = _frustum[ i ].x * matrix.n14 + _frustum[ i ].y * matrix.n24 + _frustum[ i ].z * matrix.n34 + _frustum[ i ].w;
			if ( distance <= radius ) return false;

		}

		return true;

	};

	function addToFixedArray( where, what ) {

		where.list[ where.count ] = what;
		where.count += 1;

	};

	function unrollImmediateBufferMaterials( globject ) {

		var i, l, m, ml, material,
			object = globject.object,
			opaque = globject.opaque,
			transparent = globject.transparent;

		transparent.count = 0;
		opaque.count = 0;

		for ( m = 0, ml = object.materials.length; m < ml; m ++ ) {

			material = object.materials[ m ];
			material.transparent ? addToFixedArray( transparent, material ) : addToFixedArray( opaque, material );

		}

	};

	function unrollBufferMaterials( globject ) {

		var i, l, m, ml, material, meshMaterial,
			object = globject.object,
			buffer = globject.buffer,
			opaque = globject.opaque,
			transparent = globject.transparent;

		transparent.count = 0;
		opaque.count = 0;

		for ( m = 0, ml = object.materials.length; m < ml; m ++ ) {

			meshMaterial = object.materials[ m ];

			if ( meshMaterial instanceof THREE.MeshFaceMaterial ) {

				for ( i = 0, l = buffer.materials.length; i < l; i ++ ) {

					material = buffer.materials[ i ];
					if ( material ) material.transparent ? addToFixedArray( transparent, material ) : addToFixedArray( opaque, material );

				}

			} else {

				material = meshMaterial;
				if ( material ) material.transparent ? addToFixedArray( transparent, material ) : addToFixedArray( opaque, material );

			}

		}

	};

	function painterSort( a, b ) {

		return b.z - a.z;

	};

	function renderShadowMap( scene, camera ) {

		var i, il, light,
			j = 0,
			shadowMap, shadowMatrix,
			oil,
			material,
			o, ol, webglObject, object,
			lights = scene.lights,
			fog = null;

		if ( ! _cameraLight ) {

			_cameraLight = new THREE.Camera( _this.shadowCameraFov, camera.aspect, _this.shadowCameraNear, _this.shadowCameraFar );

		}

		for ( i = 0, il = lights.length; i < il; i ++ ) {

			light = lights[ i ];

			if ( light instanceof THREE.SpotLight && light.castShadow ) {

				if ( ! _this.shadowMap[ j ] ) {

					var pars = { minFilter: THREE.LinearFilter, magFilter: THREE.LinearFilter, format: THREE.RGBAFormat };
					_this.shadowMap[ j ] = new THREE.WebGLRenderTarget( _this.shadowMapWidth, _this.shadowMapHeight, pars );

				}

				if ( ! _shadowMatrix[ j ] ) {

					_shadowMatrix[ j ] = new THREE.Matrix4();

				}

				shadowMap = _this.shadowMap[ j ];
				shadowMatrix = _shadowMatrix[ j ];

				_cameraLight.position.copy( light.position );
				_cameraLight.target.position.copy( light.target.position );

				_cameraLight.update( undefined, true );

				scene.update( undefined, false, _cameraLight );

				// compute shadow matrix

				shadowMatrix.set( 0.5, 0.0, 0.0, 0.5,
								  0.0, 0.5, 0.0, 0.5,
								  0.0, 0.0, 0.5, 0.5,
								  0.0, 0.0, 0.0, 1.0 );

				shadowMatrix.multiplySelf( _cameraLight.projectionMatrix );
				shadowMatrix.multiplySelf( _cameraLight.matrixWorldInverse );

				// render shadow map

				_cameraLight.matrixWorldInverse.flattenToArray( _viewMatrixArray );
				_cameraLight.projectionMatrix.flattenToArray( _projectionMatrixArray );

				_projScreenMatrix.multiply( _cameraLight.projectionMatrix, _cameraLight.matrixWorldInverse );
				computeFrustum( _projScreenMatrix );

				_this.initWebGLObjects( scene );

				setRenderTarget( shadowMap );

				// using arbitrary clear color in depth pass
				// creates variance in shadows

				_gl.clearColor( 1, 1, 1, 1 );
				//_gl.clearColor( 0, 0, 0, 1 );

				_this.clear();

				_gl.clearColor( _clearColor.r, _clearColor.g, _clearColor.b, _clearAlpha );


				// set matrices & frustum culling

				ol = scene.__webglObjects.length;
				oil = scene.__webglObjectsImmediate.length;

				for ( o = 0; o < ol; o ++ ) {

					webglObject = scene.__webglObjects[ o ];
					object = webglObject.object;

					if ( object.visible && object.castShadow ) {

						if ( ! ( object instanceof THREE.Mesh ) || isInFrustum( object ) ) {

							object.matrixWorld.flattenToArray( object._objectMatrixArray );

							setupMatrices( object, _cameraLight, false );

							webglObject.render = true;

						} else {

							webglObject.render = false;

						}

					} else {

						webglObject.render = false;

					}

				}

				setDepthTest( true );
				setBlending( THREE.NormalBlending ); // maybe blending should be just disabled?

				//_gl.cullFace( _gl.FRONT );

				for ( o = 0; o < ol; o ++ ) {

					webglObject = scene.__webglObjects[ o ];

					if ( webglObject.render ) {

						object = webglObject.object;
						buffer = webglObject.buffer;

						setObjectFaces( object );

						if ( object.customDepthMaterial ) {

							material =  object.customDepthMaterial;

						} else if ( object.geometry.morphTargets.length ) {

							material =  _depthMaterialMorph;

						} else {

							material = _depthMaterial;

						}

						renderBuffer( _cameraLight, lights, fog, material, buffer, object );

					}

				}


				for ( o = 0; o < oil; o ++ ) {

					webglObject = scene.__webglObjectsImmediate[ o ];
					object = webglObject.object;

					if ( object.visible && object.castShadow ) {

						if( object.matrixAutoUpdate ) {

							object.matrixWorld.flattenToArray( object._objectMatrixArray );

						}

						setupMatrices( object, _cameraLight, false );

						setObjectFaces( object );

						program = setProgram( _cameraLight, lights, fog, _depthMaterial, object );
						object.render( function( object ) { renderBufferImmediate( object, program, _depthMaterial.shading ); } );

					}

				}

				//_gl.cullFace( _gl.BACK );

				j ++;

			}

		}

	};

	this.render = function( scene, camera, renderTarget, forceClear ) {

		var i, program, opaque, transparent, material,
			o, ol, oil, webglObject, object, buffer,
			lights = scene.lights,
			fog = scene.fog;

		if ( this.shadowMapEnabled ) renderShadowMap( scene, camera );

		_this.data.vertices = 0;
		_this.data.faces = 0;
		_this.data.drawCalls = 0;

		camera.matrixAutoUpdate && camera.update( undefined, true );

		scene.update( undefined, false, camera );

		camera.matrixWorldInverse.flattenToArray( _viewMatrixArray );
		camera.projectionMatrix.flattenToArray( _projectionMatrixArray );

		_projScreenMatrix.multiply( camera.projectionMatrix, camera.matrixWorldInverse );
		computeFrustum( _projScreenMatrix );

		this.initWebGLObjects( scene );

		setRenderTarget( renderTarget );

		if ( this.autoClear || forceClear ) {

			this.clear();

		}

		// set matrices

		ol = scene.__webglObjects.length;

		for ( o = 0; o < ol; o ++ ) {

			webglObject = scene.__webglObjects[ o ];
			object = webglObject.object;

			if ( object.visible ) {

				if ( ! ( object instanceof THREE.Mesh ) || isInFrustum( object ) ) {

					object.matrixWorld.flattenToArray( object._objectMatrixArray );

					setupMatrices( object, camera, true );

					unrollBufferMaterials( webglObject );

					webglObject.render = true;

					if ( this.sortObjects ) {

						if ( webglObject.object.renderDepth ) {

							webglObject.z = webglObject.object.renderDepth;

						} else {

							_vector3.copy( object.position );
							_projScreenMatrix.multiplyVector3( _vector3 );

							webglObject.z = _vector3.z;

						}

					}

				} else {

					webglObject.render = false;

				}

			} else {

				webglObject.render = false;

			}

		}

		if ( this.sortObjects ) {

			scene.__webglObjects.sort( painterSort );

		}

		oil = scene.__webglObjectsImmediate.length;

		for ( o = 0; o < oil; o ++ ) {

			webglObject = scene.__webglObjectsImmediate[ o ];
			object = webglObject.object;

			if ( object.visible ) {

				if( object.matrixAutoUpdate ) {

					object.matrixWorld.flattenToArray( object._objectMatrixArray );

				}

				setupMatrices( object, camera, true );

				unrollImmediateBufferMaterials( webglObject );

			}

		}

		if ( scene.overrideMaterial ) {

			setDepthTest( scene.overrideMaterial.depthTest );
			setBlending( scene.overrideMaterial.blending );

			for ( o = 0; o < ol; o ++ ) {

				webglObject = scene.__webglObjects[ o ];

				if ( webglObject.render ) {

					object = webglObject.object;
					buffer = webglObject.buffer;

					setObjectFaces( object );

					renderBuffer( camera, lights, fog, scene.overrideMaterial, buffer, object );

				}

			}

			for ( o = 0; o < oil; o ++ ) {

				webglObject = scene.__webglObjectsImmediate[ o ];
				object = webglObject.object;

				if ( object.visible ) {

					setObjectFaces( object );

					program = setProgram( camera, lights, fog, scene.overrideMaterial, object );
					object.render( function( object ) { renderBufferImmediate( object, program, scene.overrideMaterial.shading ); } );

				}

			}

		} else {

			// opaque pass
			// (front-to-back order)

			setBlending( THREE.NormalBlending );

			for ( o = ol - 1; o >= 0; o -- ) {

				webglObject = scene.__webglObjects[ o ];

				if ( webglObject.render ) {

					object = webglObject.object;
					buffer = webglObject.buffer;
					opaque = webglObject.opaque;

					setObjectFaces( object );

					for ( i = 0; i < opaque.count; i ++ ) {

						material = opaque.list[ i ];

						setDepthTest( material.depthTest );
						setPolygonOffset( material.polygonOffset, material.polygonOffsetFactor, material.polygonOffsetUnits );
						renderBuffer( camera, lights, fog, material, buffer, object );

					}

				}

			}

			// opaque pass (immediate simulator)

			for ( o = 0; o < oil; o++ ) {

				webglObject = scene.__webglObjectsImmediate[ o ];
				object = webglObject.object;

				if ( object.visible ) {

					opaque = webglObject.opaque;

					setObjectFaces( object );

					for( i = 0; i < opaque.count; i++ ) {

						material = opaque.list[ i ];

						setDepthTest( material.depthTest );
						setPolygonOffset( material.polygonOffset, material.polygonOffsetFactor, material.polygonOffsetUnits );

						program = setProgram( camera, lights, fog, material, object );
						object.render( function( object ) { renderBufferImmediate( object, program, material.shading ); } );

					}

				}

			}

			// transparent pass
			// (back-to-front order)

			for ( o = 0; o < ol; o ++ ) {

				webglObject = scene.__webglObjects[ o ];

				if ( webglObject.render ) {

					object = webglObject.object;
					buffer = webglObject.buffer;
					transparent = webglObject.transparent;

					setObjectFaces( object );

					for ( i = 0; i < transparent.count; i ++ ) {

						material = transparent.list[ i ];

						setBlending( material.blending );
						setDepthTest( material.depthTest );
						setPolygonOffset( material.polygonOffset, material.polygonOffsetFactor, material.polygonOffsetUnits );

						renderBuffer( camera, lights, fog, material, buffer, object );

					}

				}

			}

			// transparent pass (immediate simulator)

			for ( o = 0; o < oil; o++ ) {

				webglObject = scene.__webglObjectsImmediate[ o ];
				object = webglObject.object;

				if ( object.visible ) {

					transparent = webglObject.transparent;

					setObjectFaces( object );

					for ( i = 0; i < transparent.count; i ++ ) {

						material = transparent.list[ i ];

						setBlending( material.blending );
						setDepthTest( material.depthTest );
						setPolygonOffset( material.polygonOffset, material.polygonOffsetFactor, material.polygonOffsetUnits );

						program = setProgram( camera, lights, fog, material, object );
						object.render( function( object ) { renderBufferImmediate( object, program, material.shading ); } );

					}

				}

			}

		}

		// render 2d

		if ( scene.__webglSprites.length ) {

			renderSprites( scene, camera );

		}

		// Generate mipmap if we're using any kind of mipmap filtering

		if ( renderTarget && renderTarget.minFilter !== THREE.NearestFilter && renderTarget.minFilter !== THREE.LinearFilter ) {

			updateRenderTargetMipmap( renderTarget );

		}

		//_gl.finish();

	};

	/*
	 * Render sprites
	 *
	 */

	function renderSprites( scene, camera ) {

		var o, ol, object;
		var attributes = _sprite.attributes;
		var uniforms = _sprite.uniforms;
		var anyCustom = false;
		var invAspect = _viewportHeight / _viewportWidth;
		var size, scale = [];
		var screenPosition;
		var halfViewportWidth = _viewportWidth * 0.5;
		var halfViewportHeight = _viewportHeight * 0.5;
		var mergeWith3D = true;

		// setup gl

		_gl.useProgram( _sprite.program );
		_currentProgram = _sprite.program;
		_oldBlending = -1;
		_oldDepth = -1;

		if ( !_spriteAttributesEnabled ) {

			_gl.enableVertexAttribArray( _sprite.attributes.position );
			_gl.enableVertexAttribArray( _sprite.attributes.uv );

			_spriteAttributesEnabled = true;

		}

		_gl.disable( _gl.CULL_FACE );
		_gl.enable( _gl.BLEND );
		_gl.depthMask( true );

		_gl.bindBuffer( _gl.ARRAY_BUFFER, _sprite.vertexBuffer );
		_gl.vertexAttribPointer( attributes.position, 2, _gl.FLOAT, false, 2 * 8, 0 );
		_gl.vertexAttribPointer( attributes.uv, 2, _gl.FLOAT, false, 2 * 8, 8 );

		_gl.bindBuffer( _gl.ELEMENT_ARRAY_BUFFER, _sprite.elementBuffer );

		_gl.uniformMatrix4fv( uniforms.projectionMatrix, false, _projectionMatrixArray );

		_gl.activeTexture( _gl.TEXTURE0 );
		_gl.uniform1i( uniforms.map, 0 );

		// update positions and sort

		for( o = 0, ol = scene.__webglSprites.length; o < ol; o++ ) {

			object = scene.__webglSprites[ o ];

			if( !object.useScreenCoordinates ) {

				object._modelViewMatrix.multiplyToArray( camera.matrixWorldInverse, object.matrixWorld, object._modelViewMatrixArray );
				object.z = -object._modelViewMatrix.n34;

			} else {

				object.z = -object.position.z;

			}

		}

		scene.__webglSprites.sort( painterSort );

		// render all non-custom shader sprites

		for ( o = 0, ol = scene.__webglSprites.length; o < ol; o++ ) {

			object = scene.__webglSprites[ o ];

			if ( object.material === undefined ) {

				if ( object.map && object.map.image && object.map.image.width ) {

					if ( object.useScreenCoordinates ) {

						_gl.uniform1i( uniforms.useScreenCoordinates, 1 );
						_gl.uniform3f( uniforms.screenPosition, ( object.position.x - halfViewportWidth  ) / halfViewportWidth,
																( halfViewportHeight - object.position.y ) / halfViewportHeight,
																  Math.max( 0, Math.min( 1, object.position.z )));

					} else {



						_gl.uniform1i( uniforms.useScreenCoordinates, 0 );
						_gl.uniform1i( uniforms.affectedByDistance, object.affectedByDistance ? 1 : 0 );
						_gl.uniformMatrix4fv( uniforms.modelViewMatrix, false, object._modelViewMatrixArray );

					}

					size = object.map.image.width / ( object.scaleByViewport ? _viewportHeight : 1 );
					scale[ 0 ] = size * invAspect * object.scale.x;
					scale[ 1 ] = size * object.scale.y;

					_gl.uniform2f( uniforms.uvScale, object.uvScale.x, object.uvScale.y );
					_gl.uniform2f( uniforms.uvOffset, object.uvOffset.x, object.uvOffset.y );
					_gl.uniform2f( uniforms.alignment, object.alignment.x, object.alignment.y );
					_gl.uniform1f( uniforms.opacity, object.opacity );
					_gl.uniform1f( uniforms.rotation, object.rotation );
					_gl.uniform2fv( uniforms.scale, scale );

					if ( object.mergeWith3D && !mergeWith3D ) {

						_gl.enable( _gl.DEPTH_TEST );
						mergeWith3D = true;

					} else if ( !object.mergeWith3D && mergeWith3D ) {

						_gl.disable( _gl.DEPTH_TEST );
						mergeWith3D = false;

					}

					setBlending( object.blending );
					setTexture( object.map, 0 );

					_gl.drawElements( _gl.TRIANGLES, 6, _gl.UNSIGNED_SHORT, 0 );
				}

			} else {

				anyCustom = true;

			}

		}


		// loop through all custom

		/*
		if( anyCustom ) {

		}
		*/

		// restore gl

		_gl.enable( _gl.CULL_FACE );
		_gl.enable( _gl.DEPTH_TEST );
		_gl.depthMask( _currentDepthMask );

	}

	function setupMatrices( object, camera, computeNormalMatrix ) {

		object._modelViewMatrix.multiplyToArray( camera.matrixWorldInverse, object.matrixWorld, object._modelViewMatrixArray );

		if ( computeNormalMatrix ) {

			THREE.Matrix4.makeInvert3x3( object._modelViewMatrix ).transposeIntoArray( object._normalMatrixArray );

		}

	}

	this.initWebGLObjects = function ( scene ) {

		if ( !scene.__webglObjects ) {

			scene.__webglObjects = [];
			scene.__webglObjectsImmediate = [];
			scene.__webglSprites = [];

		}

		while ( scene.__objectsAdded.length ) {

			addObject( scene.__objectsAdded[ 0 ], scene );
			scene.__objectsAdded.splice( 0, 1 );

		}

		while ( scene.__objectsRemoved.length ) {

			removeObject( scene.__objectsRemoved[ 0 ], scene );
			scene.__objectsRemoved.splice( 0, 1 );

		}

		// update must be called after objects adding / removal

		for ( var o = 0, ol = scene.__webglObjects.length; o < ol; o ++ ) {

			updateObject( scene.__webglObjects[ o ].object, scene );

		}

	};

	function addObject( object, scene ) {

		var g, geometry, geometryGroup;

		if ( object._modelViewMatrix == undefined ) {

			object._modelViewMatrix = new THREE.Matrix4();

			object._normalMatrixArray = new Float32Array( 9 );
			object._modelViewMatrixArray = new Float32Array( 16 );
			object._objectMatrixArray = new Float32Array( 16 );

			object.matrixWorld.flattenToArray( object._objectMatrixArray );

		}

		if ( object instanceof THREE.Mesh ) {

			geometry = object.geometry;

			if ( geometry.geometryGroups == undefined ) {

				sortFacesByMaterial( geometry );

			}

			// create separate VBOs per geometry chunk

			for ( g in geometry.geometryGroups ) {

				geometryGroup = geometry.geometryGroups[ g ];

				// initialise VBO on the first access

				if ( ! geometryGroup.__webglVertexBuffer ) {

					createMeshBuffers( geometryGroup );
					initMeshBuffers( geometryGroup, object );

					geometry.__dirtyVertices = true;
					geometry.__dirtyMorphTargets = true;
					geometry.__dirtyElements = true;
					geometry.__dirtyUvs = true;
					geometry.__dirtyNormals = true;
					geometry.__dirtyTangents = true;
					geometry.__dirtyColors = true;

				}

				addBuffer( scene.__webglObjects, geometryGroup, object );

			}

		} else if ( object instanceof THREE.Ribbon ) {

			geometry = object.geometry;

			if( ! geometry.__webglVertexBuffer ) {

				createRibbonBuffers( geometry );
				initRibbonBuffers( geometry );

				geometry.__dirtyVertices = true;
				geometry.__dirtyColors = true;

			}

			addBuffer( scene.__webglObjects, geometry, object );

		} else if ( object instanceof THREE.Line ) {

			geometry = object.geometry;

			if( ! geometry.__webglVertexBuffer ) {

				createLineBuffers( geometry );
				initLineBuffers( geometry );

				geometry.__dirtyVertices = true;
				geometry.__dirtyColors = true;

			}

			addBuffer( scene.__webglObjects, geometry, object );

		} else if ( object instanceof THREE.ParticleSystem ) {

			geometry = object.geometry;

			if ( ! geometry.__webglVertexBuffer ) {

				createParticleBuffers( geometry );
				initParticleBuffers( geometry, object );

				geometry.__dirtyVertices = true;
				geometry.__dirtyColors = true;

			}

			addBuffer( scene.__webglObjects, geometry, object );

		} else if ( THREE.MarchingCubes !== undefined && object instanceof THREE.MarchingCubes ) {

			addBufferImmediate( scene.__webglObjectsImmediate, object );

		} else if ( object instanceof THREE.Sprite ) {

			scene.__webglSprites.push( object );

		}

		/*else if ( object instanceof THREE.Particle ) {

		}*/

	};

	function areCustomAttributesDirty( geometryGroup ) {

		var a, m, ml, material, materials;

		materials = geometryGroup.__materials;

		for ( m = 0, ml = materials.length; m < ml; m ++ ) {

			material = materials[ m ];

			if ( material.attributes ) {

				for ( a in material.attributes ) {

					if ( material.attributes[ a ].needsUpdate ) return true;

				}

			}

		}


		return false;

	};

	function clearCustomAttributes( geometryGroup ) {

		var a, m, ml, material, materials;

		materials = geometryGroup.__materials;

		for ( m = 0, ml = materials.length; m < ml; m ++ ) {

			material = materials[ m ];

			if ( material.attributes ) {

				for ( a in material.attributes ) {

					material.attributes[ a ].needsUpdate = false;

				}

			}

		}

	};

	function updateObject( object, scene ) {

		var g, geometry, geometryGroup, a, customAttributeDirty;

		if ( object instanceof THREE.Mesh ) {

			geometry = object.geometry;

			// check all geometry groups

			for ( g in geometry.geometryGroups ) {

				geometryGroup = geometry.geometryGroups[ g ];

				customAttributeDirty = areCustomAttributesDirty( geometryGroup );

				if ( geometry.__dirtyVertices || geometry.__dirtyMorphTargets || geometry.__dirtyElements ||
					 geometry.__dirtyUvs || geometry.__dirtyNormals ||
					 geometry.__dirtyColors || geometry.__dirtyTangents || customAttributeDirty ) {

					setMeshBuffers( geometryGroup, object, _gl.DYNAMIC_DRAW, !geometry.dynamic );

				}

			}

			geometry.__dirtyVertices = false;
			geometry.__dirtyMorphTargets = false;
			geometry.__dirtyElements = false;
			geometry.__dirtyUvs = false;
			geometry.__dirtyNormals = false;
			geometry.__dirtyTangents = false;
			geometry.__dirtyColors = false;

			clearCustomAttributes( geometryGroup );

		} else if ( object instanceof THREE.Ribbon ) {

			geometry = object.geometry;

			if( geometry.__dirtyVertices || geometry.__dirtyColors ) {

				setRibbonBuffers( geometry, _gl.DYNAMIC_DRAW );

			}

			geometry.__dirtyVertices = false;
			geometry.__dirtyColors = false;

		} else if ( object instanceof THREE.Line ) {

			geometry = object.geometry;

			if( geometry.__dirtyVertices ||  geometry.__dirtyColors ) {

				setLineBuffers( geometry, _gl.DYNAMIC_DRAW );

			}

			geometry.__dirtyVertices = false;
			geometry.__dirtyColors = false;

		} else if ( object instanceof THREE.ParticleSystem ) {

			geometry = object.geometry;

			customAttributeDirty = areCustomAttributesDirty( geometry );

			if ( geometry.__dirtyVertices || geometry.__dirtyColors || object.sortParticles || customAttributeDirty ) {

				setParticleBuffers( geometry, _gl.DYNAMIC_DRAW, object );

			}

			geometry.__dirtyVertices = false;
			geometry.__dirtyColors = false;

			clearCustomAttributes( geometry );

		}/* else if ( THREE.MarchingCubes !== undefined && object instanceof THREE.MarchingCubes ) {

			// it updates itself in render callback

		} else if ( object instanceof THREE.Particle ) {

		}*/

		/*
		delete geometry.vertices;
		delete geometry.faces;
		delete geometryGroup.faces;
		*/

	};

	function removeInstances( objlist, object ) {

		var o, ol;

		for ( o = objlist.length - 1; o >= 0; o -- ) {

			if ( objlist[ o ].object == object ) {

				objlist.splice( o, 1 );

			}

		}

	};

	function removeInstancesDirect( objlist, object ) {

		var o, ol;

		for ( o = objlist.length - 1; o >= 0; o -- ) {

			if ( objlist[ o ] == object ) {

				objlist.splice( o, 1 );

			}

		}

	};

	function removeObject( object, scene ) {

		if ( object instanceof THREE.Mesh  ||
			 object instanceof THREE.ParticleSystem ||
			 object instanceof THREE.Ribbon ||
			 object instanceof THREE.Line ) {

			removeInstances( scene.__webglObjects, object );

		} else if ( object instanceof THREE.Sprite ) {

			removeInstancesDirect( scene.__webglSprites, object );

		} else if ( object instanceof THREE.MarchingCubes ) {

			removeInstances( scene.__webglObjectsImmediate, object );

		}

	};

	function sortFacesByMaterial( geometry ) {

		// TODO
		// Should optimize by grouping faces with ColorFill / ColorStroke materials
		// which could then use vertex color attributes instead of each being
		// in its separate VBO

		var i, l, f, fl, face, material, materials, vertices, mhash, ghash, hash_map = {};
		var numMorphTargets = geometry.morphTargets !== undefined ? geometry.morphTargets.length : 0;

		geometry.geometryGroups = {};

		function materialHash( material ) {

			var hash_array = [];

			for ( i = 0, l = material.length; i < l; i++ ) {

				if ( material[ i ] == undefined ) {

					hash_array.push( "undefined" );

				} else {

					hash_array.push( material[ i ].id );

				}

			}

			return hash_array.join( '_' );

		}

		for ( f = 0, fl = geometry.faces.length; f < fl; f++ ) {

			face = geometry.faces[ f ];
			materials = face.materials;

			mhash = materialHash( materials );

			if ( hash_map[ mhash ] == undefined ) {

				hash_map[ mhash ] = { 'hash': mhash, 'counter': 0 };

			}

			ghash = hash_map[ mhash ].hash + '_' + hash_map[ mhash ].counter;

			if ( geometry.geometryGroups[ ghash ] == undefined ) {

				geometry.geometryGroups[ ghash ] = { 'faces': [], 'materials': materials, 'vertices': 0, 'numMorphTargets': numMorphTargets };

			}

			vertices = face instanceof THREE.Face3 ? 3 : 4;

			if ( geometry.geometryGroups[ ghash ].vertices + vertices > 65535 ) {

				hash_map[ mhash ].counter += 1;
				ghash = hash_map[ mhash ].hash + '_' + hash_map[ mhash ].counter;

				if ( geometry.geometryGroups[ ghash ] == undefined ) {

					geometry.geometryGroups[ ghash ] = { 'faces': [], 'materials': materials, 'vertices': 0, 'numMorphTargets': numMorphTargets };

				}

			}

			geometry.geometryGroups[ ghash ].faces.push( f );
			geometry.geometryGroups[ ghash ].vertices += vertices;

		}

	};

	function addBuffer( objlist, buffer, object ) {

		objlist.push( {
			buffer: buffer, object: object,
			opaque: { list: [], count: 0 },
			transparent: { list: [], count: 0 }
		} );

	};

	function addBufferImmediate( objlist, object ) {

		objlist.push( {
			object: object,
			opaque: { list: [], count: 0 },
			transparent: { list: [], count: 0 }
		} );

	};

	this.setFaceCulling = function ( cullFace, frontFace ) {

		if ( cullFace ) {

			if ( !frontFace || frontFace == "ccw" ) {

				_gl.frontFace( _gl.CCW );

			} else {

				_gl.frontFace( _gl.CW );

			}

			if( cullFace == "back" ) {

				_gl.cullFace( _gl.BACK );

			} else if( cullFace == "front" ) {

				_gl.cullFace( _gl.FRONT );

			} else {

				_gl.cullFace( _gl.FRONT_AND_BACK );

			}

			_gl.enable( _gl.CULL_FACE );

		} else {

			_gl.disable( _gl.CULL_FACE );

		}

	};

	this.supportsVertexTextures = function () {

		return _supportsVertexTextures;

	};

	function maxVertexTextures() {

		return _gl.getParameter( _gl.MAX_VERTEX_TEXTURE_IMAGE_UNITS );

	};

	function buildProgram( shaderID, fragmentShader, vertexShader, uniforms, attributes, parameters ) {

		var p, pl, program, code;
		var chunks = [];

		// Generate code

		if ( shaderID ) {

			chunks.push( shaderID );

		} else {

			chunks.push( fragmentShader );
			chunks.push( vertexShader );

		}

		for ( p in parameters ) {

			chunks.push( p );
			chunks.push( parameters[ p ] );

		}

		code = chunks.join();

		// Check if code has been already compiled

		for ( p = 0, pl = _programs.length; p < pl; p ++ ) {

			if ( _programs[ p ].code == code ) {

				// console.log( "Code already compiled." /*: \n\n" + code*/ );

				return _programs[ p ].program;

			}

		}

		//console.log( "building new program " );

		//

		program = _gl.createProgram();

		var prefix_vertex = [

			_supportsVertexTextures ? "#define VERTEX_TEXTURES" : "",

			"#define MAX_DIR_LIGHTS " + parameters.maxDirLights,
			"#define MAX_POINT_LIGHTS " + parameters.maxPointLights,

			"#define MAX_SHADOWS " + parameters.maxShadows,

			"#define MAX_BONES " + parameters.maxBones,

			parameters.map ? "#define USE_MAP" : "",
			parameters.envMap ? "#define USE_ENVMAP" : "",
			parameters.lightMap ? "#define USE_LIGHTMAP" : "",
			parameters.vertexColors ? "#define USE_COLOR" : "",
			parameters.skinning ? "#define USE_SKINNING" : "",
			parameters.morphTargets ? "#define USE_MORPHTARGETS" : "",

			parameters.shadowMapEnabled ? "#define USE_SHADOWMAP" : "",
			parameters.shadowMapSoft ? "#define SHADOWMAP_SOFT" : "",

			parameters.sizeAttenuation ? "#define USE_SIZEATTENUATION" : "",

			"uniform mat4 objectMatrix;",
			"uniform mat4 modelViewMatrix;",
			"uniform mat4 projectionMatrix;",
			"uniform mat4 viewMatrix;",
			"uniform mat3 normalMatrix;",
			"uniform vec3 cameraPosition;",

			"uniform mat4 cameraInverseMatrix;",

			"attribute vec3 position;",
			"attribute vec3 normal;",
			"attribute vec2 uv;",
			"attribute vec2 uv2;",

			"#ifdef USE_COLOR",

				"attribute vec3 color;",

			"#endif",

			"#ifdef USE_MORPHTARGETS",

				"attribute vec3 morphTarget0;",
				"attribute vec3 morphTarget1;",
				"attribute vec3 morphTarget2;",
				"attribute vec3 morphTarget3;",
				"attribute vec3 morphTarget4;",
				"attribute vec3 morphTarget5;",
				"attribute vec3 morphTarget6;",
				"attribute vec3 morphTarget7;",

			"#endif",

			"#ifdef USE_SKINNING",

				"attribute vec4 skinVertexA;",
				"attribute vec4 skinVertexB;",
				"attribute vec4 skinIndex;",
				"attribute vec4 skinWeight;",

			"#endif",

			""

		].join("\n");

		var prefix_fragment = [

			"#ifdef GL_ES",
			"precision highp float;",
			"#endif",

			"#define MAX_DIR_LIGHTS " + parameters.maxDirLights,
			"#define MAX_POINT_LIGHTS " + parameters.maxPointLights,

			"#define MAX_SHADOWS " + parameters.maxShadows,

			parameters.alphaTest ? "#define ALPHATEST " + parameters.alphaTest: "",

			parameters.fog ? "#define USE_FOG" : "",
			parameters.fog instanceof THREE.FogExp2 ? "#define FOG_EXP2" : "",

			parameters.map ? "#define USE_MAP" : "",
			parameters.envMap ? "#define USE_ENVMAP" : "",
			parameters.lightMap ? "#define USE_LIGHTMAP" : "",
			parameters.vertexColors ? "#define USE_COLOR" : "",

			parameters.shadowMapEnabled ? "#define USE_SHADOWMAP" : "",
			parameters.shadowMapSoft ? "#define SHADOWMAP_SOFT" : "",
			parameters.shadowMapSoft ? "#define SHADOWMAP_WIDTH " + parameters.shadowMapWidth.toFixed( 1 ) : "",
			parameters.shadowMapSoft ? "#define SHADOWMAP_HEIGHT " + parameters.shadowMapHeight.toFixed( 1 ) : "",

			"uniform mat4 viewMatrix;",
			"uniform vec3 cameraPosition;",
			""

		].join("\n");

		_gl.attachShader( program, getShader( "fragment", prefix_fragment + fragmentShader ) );
		_gl.attachShader( program, getShader( "vertex", prefix_vertex + vertexShader ) );

		_gl.linkProgram( program );

		if ( !_gl.getProgramParameter( program, _gl.LINK_STATUS ) ) {

			console.error( "Could not initialise shader\n" + "VALIDATE_STATUS: " + _gl.getProgramParameter( program, _gl.VALIDATE_STATUS ) + ", gl error [" + _gl.getError() + "]" );

		}

		//console.log( prefix_fragment + fragmentShader );
		//console.log( prefix_vertex + vertexShader );

		program.uniforms = {};
		program.attributes = {};

		var identifiers, u, a, i;

		// cache uniform locations

		identifiers = [

			'viewMatrix', 'modelViewMatrix', 'projectionMatrix', 'normalMatrix', 'objectMatrix', 'cameraPosition',
			'cameraInverseMatrix', 'boneGlobalMatrices', 'morphTargetInfluences'

		];

		for ( u in uniforms ) {

			identifiers.push( u );

		}

		cacheUniformLocations( program, identifiers );

		// cache attributes locations

		identifiers = [

			"position", "normal", "uv", "uv2", "tangent", "color",
			"skinVertexA", "skinVertexB", "skinIndex", "skinWeight"

		];

		for ( i = 0; i < parameters.maxMorphTargets; i ++ ) {

			identifiers.push( "morphTarget" + i );

		}

		for ( a in attributes ) {

			identifiers.push( a );

		}

		cacheAttributeLocations( program, identifiers );

		_programs.push( { program: program, code: code } );

		return program;

	};

	function loadUniformsSkinning( uniforms, object ) {

		_gl.uniformMatrix4fv( uniforms.cameraInverseMatrix, false, _viewMatrixArray );
		_gl.uniformMatrix4fv( uniforms.boneGlobalMatrices, false, object.boneMatrices );

	};


	function loadUniformsMatrices( uniforms, object ) {

		_gl.uniformMatrix4fv( uniforms.modelViewMatrix, false, object._modelViewMatrixArray );
		_gl.uniformMatrix3fv( uniforms.normalMatrix, false, object._normalMatrixArray );

	};

	function loadUniformsGeneric( program, uniforms ) {

		var u, uniform, value, type, location, texture, i, il;

		for( u in uniforms ) {

			location = program.uniforms[ u ];
			if ( !location ) continue;

			uniform = uniforms[ u ];

			type = uniform.type;
			value = uniform.value;

			if( type == "i" ) {

				_gl.uniform1i( location, value );

			} else if( type == "f" ) {

				_gl.uniform1f( location, value );

			} else if( type == "fv1" ) {

				_gl.uniform1fv( location, value );

			} else if( type == "fv" ) {

				_gl.uniform3fv( location, value );

			} else if( type == "v2" ) {

				_gl.uniform2f( location, value.x, value.y );

			} else if( type == "v3" ) {

				_gl.uniform3f( location, value.x, value.y, value.z );

			} else if( type == "v4" ) {

				_gl.uniform4f( location, value.x, value.y, value.z, value.w );

			} else if( type == "m4" ) {

				if ( ! uniform._array ) {

					uniform._array = new Float32Array( 16 );

				}

				value.flattenToArray( uniform._array );
				_gl.uniformMatrix4fv( location, false, uniform._array );

			} else if( type == "m4v" ) {

				if ( ! uniform._array ) {

					uniform._array = new Float32Array( 16 * value.length );

				}

				for ( i = 0, il = value.length; i < il; i ++ ) {

					value[ i ].flattenToArrayOffset( uniform._array, i * 16 );

				}

				_gl.uniformMatrix4fv( location, false, uniform._array );

			} else if( type == "c" ) {

				_gl.uniform3f( location, value.r, value.g, value.b );

			} else if( type == "t" ) {

				_gl.uniform1i( location, value );

				texture = uniform.texture;

				if ( !texture ) continue;

				if ( texture.image instanceof Array && texture.image.length == 6 ) {

					setCubeTexture( texture, value );

				} else {

					setTexture( texture, value );

				}

			} else if( type == "tv" ) {

				if ( ! uniform._array ) {

					uniform._array = [];

					for( i = 0, il = uniform.texture.length; i < il; i ++ ) {

						uniform._array[ i ] = value + i;

					}

				}

				_gl.uniform1iv( location, uniform._array );

				for( i = 0, il = uniform.texture.length; i < il; i ++ ) {

					texture = uniform.texture[ i ];

					if ( !texture ) continue;

					setTexture( texture, uniform._array[ i ] );

				}

			}

		}

	};

	function setBlending( blending ) {

		if ( blending != _oldBlending ) {

			switch ( blending ) {

				case THREE.AdditiveBlending:

					_gl.blendEquation( _gl.FUNC_ADD );
					_gl.blendFunc( _gl.SRC_ALPHA, _gl.ONE );

					break;

				case THREE.SubtractiveBlending:

					// TODO: Find blendFuncSeparate() combination

					_gl.blendEquation( _gl.FUNC_ADD );
					_gl.blendFunc( _gl.ZERO, _gl.ONE_MINUS_SRC_COLOR );

					break;

				case THREE.MultiplyBlending:

					// TODO: Find blendFuncSeparate() combination

					_gl.blendEquation( _gl.FUNC_ADD );
					_gl.blendFunc( _gl.ZERO, _gl.SRC_COLOR );

					break;

				default:

					_gl.blendEquationSeparate( _gl.FUNC_ADD, _gl.FUNC_ADD );
					_gl.blendFuncSeparate( _gl.SRC_ALPHA, _gl.ONE_MINUS_SRC_ALPHA, _gl.ONE, _gl.ONE_MINUS_SRC_ALPHA );

					break;

			}

			_oldBlending = blending;

		}

	};

	function setTextureParameters( textureType, texture, image ) {

		if ( isPowerOfTwo( image.width ) && isPowerOfTwo( image.height ) ) {

			_gl.texParameteri( textureType, _gl.TEXTURE_WRAP_S, paramThreeToGL( texture.wrapS ) );
			_gl.texParameteri( textureType, _gl.TEXTURE_WRAP_T, paramThreeToGL( texture.wrapT ) );

			_gl.texParameteri( textureType, _gl.TEXTURE_MAG_FILTER, paramThreeToGL( texture.magFilter ) );
			_gl.texParameteri( textureType, _gl.TEXTURE_MIN_FILTER, paramThreeToGL( texture.minFilter ) );

			_gl.generateMipmap( textureType );

		} else {

			_gl.texParameteri( textureType, _gl.TEXTURE_WRAP_S, _gl.CLAMP_TO_EDGE );
			_gl.texParameteri( textureType, _gl.TEXTURE_WRAP_T, _gl.CLAMP_TO_EDGE );

			_gl.texParameteri( textureType, _gl.TEXTURE_MAG_FILTER, filterFallback( texture.magFilter ) );
			_gl.texParameteri( textureType, _gl.TEXTURE_MIN_FILTER, filterFallback( texture.minFilter ) );

		}

	};

	function setTexture( texture, slot ) {

		if ( texture.needsUpdate ) {

			if ( ! texture.__webglInit ) {

				texture.__webglTexture = _gl.createTexture();
				texture.__webglInit = true;

			}

			_gl.bindTexture( _gl.TEXTURE_2D, texture.__webglTexture );

			if ( texture.image.data ) {

				_gl.texImage2D( _gl.TEXTURE_2D, 0, paramThreeToGL( texture.format ), texture.image.width, texture.image.height, 0, paramThreeToGL( texture.format ), _gl.UNSIGNED_BYTE, texture.image.data );

			} else {

				_gl.texImage2D( _gl.TEXTURE_2D, 0, _gl.RGBA, _gl.RGBA, _gl.UNSIGNED_BYTE, texture.image );

			}

			setTextureParameters( _gl.TEXTURE_2D, texture, texture.image );

			_gl.bindTexture( _gl.TEXTURE_2D, null );

			texture.needsUpdate = false;

		}

		/*
		if ( texture.needsUpdate ) {

			if ( !texture.__webglInit ) {

				texture.__webglTexture = _gl.createTexture();

				_gl.bindTexture( _gl.TEXTURE_2D, texture.__webglTexture );
				_gl.texImage2D( _gl.TEXTURE_2D, 0, _gl.RGBA, _gl.RGBA, _gl.UNSIGNED_BYTE, texture.image );

				texture.__webglInit = true;

			} else {

				_gl.bindTexture( _gl.TEXTURE_2D, texture.__webglTexture );
				 _gl.texSubImage2D( _gl.TEXTURE_2D, 0, 0, 0, _gl.RGBA, _gl.UNSIGNED_BYTE, texture.image );

			}

			setTextureParameters( _gl.TEXTURE_2D, texture, texture.image );

			_gl.bindTexture( _gl.TEXTURE_2D, null );

			texture.needsUpdate = false;

		}
		*/

		_gl.activeTexture( _gl.TEXTURE0 + slot );
		_gl.bindTexture( _gl.TEXTURE_2D, texture.__webglTexture );


	};

	function setCubeTexture( texture, slot ) {

		if ( texture.image.length == 6 ) {

			if ( texture.needsUpdate ) {

				if ( !texture.__webglInit ) {

					texture.image.__webglTextureCube = _gl.createTexture();

					_gl.bindTexture( _gl.TEXTURE_CUBE_MAP, texture.image.__webglTextureCube );

					for ( var i = 0; i < 6; ++i ) {

						_gl.texImage2D( _gl.TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, _gl.RGBA, _gl.RGBA, _gl.UNSIGNED_BYTE, texture.image[ i ] );

					}

					texture.__webglInit = true;

				} else {

					_gl.bindTexture( _gl.TEXTURE_CUBE_MAP, texture.image.__webglTextureCube );

					for ( var i = 0; i < 6; ++i ) {

						// _gl.texImage2D( _gl.TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, _gl.RGBA, _gl.RGBA, _gl.UNSIGNED_BYTE, texture.image[ i ] );
						_gl.texSubImage2D( _gl.TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, 0, 0, _gl.RGBA, _gl.UNSIGNED_BYTE, texture.image[ i ] );

					}

				}

				setTextureParameters( _gl.TEXTURE_CUBE_MAP, texture, texture.image[0] );
				_gl.bindTexture( _gl.TEXTURE_CUBE_MAP, null );

				texture.needsUpdate = false;

			}

			_gl.activeTexture( _gl.TEXTURE0 + slot );
			_gl.bindTexture( _gl.TEXTURE_CUBE_MAP, texture.image.__webglTextureCube );

		}

	};

	function setRenderTarget( renderTexture ) {

		if ( renderTexture && !renderTexture.__webglFramebuffer ) {

			if( renderTexture.depthBuffer === undefined ) renderTexture.depthBuffer = true;
			if( renderTexture.stencilBuffer === undefined ) renderTexture.stencilBuffer = true;

			renderTexture.__webglFramebuffer = _gl.createFramebuffer();
			renderTexture.__webglRenderbuffer = _gl.createRenderbuffer();
			renderTexture.__webglTexture = _gl.createTexture();


			// Setup texture

			_gl.bindTexture( _gl.TEXTURE_2D, renderTexture.__webglTexture );
			_gl.texParameteri( _gl.TEXTURE_2D, _gl.TEXTURE_WRAP_S, paramThreeToGL( renderTexture.wrapS ) );
			_gl.texParameteri( _gl.TEXTURE_2D, _gl.TEXTURE_WRAP_T, paramThreeToGL( renderTexture.wrapT ) );
			_gl.texParameteri( _gl.TEXTURE_2D, _gl.TEXTURE_MAG_FILTER, paramThreeToGL( renderTexture.magFilter ) );
			_gl.texParameteri( _gl.TEXTURE_2D, _gl.TEXTURE_MIN_FILTER, paramThreeToGL( renderTexture.minFilter ) );
			_gl.texImage2D( _gl.TEXTURE_2D, 0, paramThreeToGL( renderTexture.format ), renderTexture.width, renderTexture.height, 0, paramThreeToGL( renderTexture.format ), paramThreeToGL( renderTexture.type ), null );

			// Setup render and frame buffer

			_gl.bindRenderbuffer( _gl.RENDERBUFFER, renderTexture.__webglRenderbuffer );
			_gl.bindFramebuffer( _gl.FRAMEBUFFER, renderTexture.__webglFramebuffer );

			_gl.framebufferTexture2D( _gl.FRAMEBUFFER, _gl.COLOR_ATTACHMENT0, _gl.TEXTURE_2D, renderTexture.__webglTexture, 0 );

			if ( renderTexture.depthBuffer && !renderTexture.stencilBuffer ) {

				_gl.renderbufferStorage( _gl.RENDERBUFFER, _gl.DEPTH_COMPONENT16, renderTexture.width, renderTexture.height );
				_gl.framebufferRenderbuffer( _gl.FRAMEBUFFER, _gl.DEPTH_ATTACHMENT, _gl.RENDERBUFFER, renderTexture.__webglRenderbuffer );

			/* For some reason this is not working. Defaulting to RGBA4.
			} else if( !renderTexture.depthBuffer && renderTexture.stencilBuffer ) {

				_gl.renderbufferStorage( _gl.RENDERBUFFER, _gl.STENCIL_INDEX8, renderTexture.width, renderTexture.height );
				_gl.framebufferRenderbuffer( _gl.FRAMEBUFFER, _gl.STENCIL_ATTACHMENT, _gl.RENDERBUFFER, renderTexture.__webglRenderbuffer );
			*/
			} else if( renderTexture.depthBuffer && renderTexture.stencilBuffer ) {

				_gl.renderbufferStorage( _gl.RENDERBUFFER, _gl.DEPTH_STENCIL, renderTexture.width, renderTexture.height );
				_gl.framebufferRenderbuffer( _gl.FRAMEBUFFER, _gl.DEPTH_STENCIL_ATTACHMENT, _gl.RENDERBUFFER, renderTexture.__webglRenderbuffer );

			} else {

				_gl.renderbufferStorage( _gl.RENDERBUFFER, _gl.RGBA4, renderTexture.width, renderTexture.height );

			}


			// Release everything

			_gl.bindTexture( _gl.TEXTURE_2D, null );
			_gl.bindRenderbuffer( _gl.RENDERBUFFER, null );
			_gl.bindFramebuffer( _gl.FRAMEBUFFER, null);

		}

		var framebuffer, width, height;

		if ( renderTexture ) {

			framebuffer = renderTexture.__webglFramebuffer;
			width = renderTexture.width;
			height = renderTexture.height;

		} else {

			framebuffer = null;
			width = _viewportWidth;
			height = _viewportHeight;

		}

		if ( framebuffer != _currentFramebuffer ) {

			_gl.bindFramebuffer( _gl.FRAMEBUFFER, framebuffer );
			_gl.viewport( _viewportX, _viewportY, width, height );

			_currentFramebuffer = framebuffer;

		}

	};

	function updateRenderTargetMipmap( renderTarget ) {

		_gl.bindTexture( _gl.TEXTURE_2D, renderTarget.__webglTexture );
		_gl.generateMipmap( _gl.TEXTURE_2D );
		_gl.bindTexture( _gl.TEXTURE_2D, null );

	};

	function cacheUniformLocations( program, identifiers ) {

		var i, l, id;

		for( i = 0, l = identifiers.length; i < l; i++ ) {

			id = identifiers[ i ];
			program.uniforms[ id ] = _gl.getUniformLocation( program, id );

		}

	};

	function cacheAttributeLocations( program, identifiers ) {

		var i, l, id;

		for( i = 0, l = identifiers.length; i < l; i++ ) {

			id = identifiers[ i ];
			program.attributes[ id ] = _gl.getAttribLocation( program, id );

		}

	};

	function getShader( type, string ) {

		var shader;

		if ( type == "fragment" ) {

			shader = _gl.createShader( _gl.FRAGMENT_SHADER );

		} else if ( type == "vertex" ) {

			shader = _gl.createShader( _gl.VERTEX_SHADER );

		}

		_gl.shaderSource( shader, string );
		_gl.compileShader( shader );

		if ( !_gl.getShaderParameter( shader, _gl.COMPILE_STATUS ) ) {

			console.error( _gl.getShaderInfoLog( shader ) );
			console.error( string );
			return null;

		}

		return shader;

	};

	// fallback filters for non-power-of-2 textures

	function filterFallback( f ) {

		switch ( f ) {

			case THREE.NearestFilter:
			case THREE.NearestMipMapNearestFilter:
			case THREE.NearestMipMapLinearFilter: return _gl.NEAREST; break;

			case THREE.LinearFilter:
			case THREE.LinearMipMapNearestFilter:
			case THREE.LinearMipMapLinearFilter:
			default:

				return _gl.LINEAR; break;

		}

	};

	function paramThreeToGL( p ) {

		switch ( p ) {

			case THREE.RepeatWrapping: return _gl.REPEAT; break;
			case THREE.ClampToEdgeWrapping: return _gl.CLAMP_TO_EDGE; break;
			case THREE.MirroredRepeatWrapping: return _gl.MIRRORED_REPEAT; break;

			case THREE.NearestFilter: return _gl.NEAREST; break;
			case THREE.NearestMipMapNearestFilter: return _gl.NEAREST_MIPMAP_NEAREST; break;
			case THREE.NearestMipMapLinearFilter: return _gl.NEAREST_MIPMAP_LINEAR; break;

			case THREE.LinearFilter: return _gl.LINEAR; break;
			case THREE.LinearMipMapNearestFilter: return _gl.LINEAR_MIPMAP_NEAREST; break;
			case THREE.LinearMipMapLinearFilter: return _gl.LINEAR_MIPMAP_LINEAR; break;

			case THREE.ByteType: return _gl.BYTE; break;
			case THREE.UnsignedByteType: return _gl.UNSIGNED_BYTE; break;
			case THREE.ShortType: return _gl.SHORT; break;
			case THREE.UnsignedShortType: return _gl.UNSIGNED_SHORT; break;
			case THREE.IntType: return _gl.INT; break;
			case THREE.UnsignedShortType: return _gl.UNSIGNED_INT; break;
			case THREE.FloatType: return _gl.FLOAT; break;

			case THREE.AlphaFormat: return _gl.ALPHA; break;
			case THREE.RGBFormat: return _gl.RGB; break;
			case THREE.RGBAFormat: return _gl.RGBA; break;
			case THREE.LuminanceFormat: return _gl.LUMINANCE; break;
			case THREE.LuminanceAlphaFormat: return _gl.LUMINANCE_ALPHA; break;

		}

		return 0;

	};

	function isPowerOfTwo( value ) {

		return ( value & ( value - 1 ) ) == 0;

	};

	function materialNeedsSmoothNormals( material ) {

		return material && material.shading != undefined && material.shading == THREE.SmoothShading;

	};

	function bufferNeedsSmoothNormals( geometryGroup, object ) {

		var m, ml, i, l, meshMaterial, needsSmoothNormals = false;

		for ( m = 0, ml = object.materials.length; m < ml; m++ ) {

			meshMaterial = object.materials[ m ];

			if ( meshMaterial instanceof THREE.MeshFaceMaterial ) {

				for ( i = 0, l = geometryGroup.materials.length; i < l; i++ ) {

					if ( materialNeedsSmoothNormals( geometryGroup.materials[ i ] ) ) {

						needsSmoothNormals = true;
						break;

					}

				}

			} else {

				if ( materialNeedsSmoothNormals( meshMaterial ) ) {

					needsSmoothNormals = true;
					break;

				}

			}

			if ( needsSmoothNormals ) break;

		}

		return needsSmoothNormals;

	};

	function unrollGroupMaterials( geometryGroup, object ) {

		var m, ml, i, il,
			material, meshMaterial,
			materials = [];

		for ( m = 0, ml = object.materials.length; m < ml; m++ ) {

			meshMaterial = object.materials[ m ];

			if ( meshMaterial instanceof THREE.MeshFaceMaterial ) {

				for ( i = 0, l = geometryGroup.materials.length; i < l; i++ ) {

					material = geometryGroup.materials[ i ];

					if ( material ) {

						materials.push( material );

					}

				}

			} else {

				material = meshMaterial;

				if ( material ) {

					materials.push( material );

				}

			}

		}

		return materials;

	};

	function bufferGuessVertexColorType( materials, geometryGroup, object ) {

		var i, m, ml = materials.length;

		// use vertexColor type from the first material in unrolled materials

		for ( i = 0; i < ml; i ++ ) {

			m = materials[ i ];

			if ( m.vertexColors ) {

				return m.vertexColors;

			}

		}

		return false;

	};

	function bufferGuessNormalType( materials, geometryGroup, object ) {

		var i, m, ml = materials.length;

		// only MeshBasicMaterial and MeshDepthMaterial don't need normals

		for ( i = 0; i < ml; i ++ ) {

			m = materials[ i ];

			if ( ( m instanceof THREE.MeshBasicMaterial && !m.envMap ) || m instanceof THREE.MeshDepthMaterial ) continue;

			if ( materialNeedsSmoothNormals( m ) ) {

				return THREE.SmoothShading;

			} else {

				return THREE.FlatShading;

			}

		}

		return false;

	};

	function bufferGuessUVType( materials, geometryGroup, object ) {

		var i, m, ml = materials.length;

		// material must use some texture to require uvs

		for ( i = 0; i < ml; i++ ) {

			m = materials[ i ];

			if ( m.map || m.lightMap || m instanceof THREE.MeshShaderMaterial ) {

				return true;

			}

		}

		return false;

	};

	function allocateBones( object ) {

		// default for when object is not specified
		// ( for example when prebuilding shader
		//   to be used with multiple objects )
		//
		// 	- leave some extra space for other uniforms
		//  - limit here is ANGLE's 254 max uniform vectors
		//    (up to 54 should be safe)

		var maxBones = 50;

		if ( object !== undefined && object instanceof THREE.SkinnedMesh ) {

			maxBones = object.bones.length;

		}

		return maxBones;

	};

	function allocateLights( lights, maxLights ) {

		var l, ll, light, dirLights, pointLights, maxDirLights, maxPointLights;
		dirLights = pointLights = maxDirLights = maxPointLights = 0;

		for ( l = 0, ll = lights.length; l < ll; l++ ) {

			light = lights[ l ];

			if ( light instanceof THREE.SpotLight ) dirLights ++; // hack, not a proper spotlight
			if ( light instanceof THREE.DirectionalLight ) dirLights ++;
			if ( light instanceof THREE.PointLight ) pointLights ++;

		}

		if ( ( pointLights + dirLights ) <= maxLights ) {

			maxDirLights = dirLights;
			maxPointLights = pointLights;

		} else {

			maxDirLights = Math.ceil( maxLights * dirLights / ( pointLights + dirLights ) );
			maxPointLights = maxLights - maxDirLights;

		}

		return { 'directional' : maxDirLights, 'point' : maxPointLights };

	};

	function allocateShadows( lights ) {

		var l, ll, light, maxShadows = 0;

		for ( l = 0, ll = lights.length; l < ll; l++ ) {

			light = lights[ l ];

			if ( light instanceof THREE.SpotLight && light.castShadow ) maxShadows ++;

		}

		return maxShadows;

	};


	/* DEBUG
	function getGLParams() {

		var params  = {

			'MAX_VARYING_VECTORS': _gl.getParameter( _gl.MAX_VARYING_VECTORS ),
			'MAX_VERTEX_ATTRIBS': _gl.getParameter( _gl.MAX_VERTEX_ATTRIBS ),

			'MAX_TEXTURE_IMAGE_UNITS': _gl.getParameter( _gl.MAX_TEXTURE_IMAGE_UNITS ),
			'MAX_VERTEX_TEXTURE_IMAGE_UNITS': _gl.getParameter( _gl.MAX_VERTEX_TEXTURE_IMAGE_UNITS ),
			'MAX_COMBINED_TEXTURE_IMAGE_UNITS' : _gl.getParameter( _gl.MAX_COMBINED_TEXTURE_IMAGE_UNITS ),

			'MAX_VERTEX_UNIFORM_VECTORS': _gl.getParameter( _gl.MAX_VERTEX_UNIFORM_VECTORS ),
			'MAX_FRAGMENT_UNIFORM_VECTORS': _gl.getParameter( _gl.MAX_FRAGMENT_UNIFORM_VECTORS )
		}

		return params;
	};

	function dumpObject( obj ) {

		var p, str = "";
		for ( p in obj ) {

			str += p + ": " + obj[p] + "\n";

		}

		return str;
	}
	*/
};

