three.js/examples/js/loaders/OBJLoader.js

/**
 * @author mrdoob / http://mrdoob.com/
 */

THREE.OBJLoader = function ( manager ) {

	this.manager = ( manager !== undefined ) ? manager : THREE.DefaultLoadingManager;

	this.materials = null;

	this.regexp = {
		// v float float float
		vertex_pattern           : /^v\s+([\d|\.|\+|\-|e|E]+)\s+([\d|\.|\+|\-|e|E]+)\s+([\d|\.|\+|\-|e|E]+)/,
		// vn float float float
		normal_pattern           : /^vn\s+([\d|\.|\+|\-|e|E]+)\s+([\d|\.|\+|\-|e|E]+)\s+([\d|\.|\+|\-|e|E]+)/,
		// vt float float
		uv_pattern               : /^vt\s+([\d|\.|\+|\-|e|E]+)\s+([\d|\.|\+|\-|e|E]+)/,
		// f vertex vertex vertex ...
		face_pattern1            : /^f\s+(-?\d+)\s+(-?\d+)\s+(-?\d+)(?:\s+(-?\d+))?/,
		// f vertex/uv vertex/uv vertex/uv ...
		face_pattern2            : /^f\s+((-?\d+)\/(-?\d+))\s+((-?\d+)\/(-?\d+))\s+((-?\d+)\/(-?\d+))(?:\s+((-?\d+)\/(-?\d+)))?/,
		// f vertex/uv/normal vertex/uv/normal vertex/uv/normal ...
		face_pattern3            : /^f\s+((-?\d+)\/(-?\d+)\/(-?\d+))\s+((-?\d+)\/(-?\d+)\/(-?\d+))\s+((-?\d+)\/(-?\d+)\/(-?\d+))(?:\s+((-?\d+)\/(-?\d+)\/(-?\d+)))?/,
		// f vertex//normal vertex//normal vertex//normal ...
		face_pattern4            : /^f\s+((-?\d+)\/\/(-?\d+))\s+((-?\d+)\/\/(-?\d+))\s+((-?\d+)\/\/(-?\d+))(?:\s+((-?\d+)\/\/(-?\d+)))?/,
		// o object_name | g group_name
		object_pattern           : /^[og]\s*(.+)?/,
		// s boolean
		smoothing_pattern        : /^s\s+(\d+|on|off)/,
		// mtllib file_reference
		material_library_pattern : /^mtllib /,
		// usemtl material_name
		material_use_pattern     : /^usemtl /
	};

};

THREE.OBJLoader.prototype = {

	constructor: THREE.OBJLoader,

	load: function ( url, onLoad, onProgress, onError ) {

		var scope = this;

		var loader = new THREE.XHRLoader( scope.manager );
		loader.setPath( this.path );
		loader.load( url, function ( text ) {

			onLoad( scope.parse( text ) );

		}, onProgress, onError );

	},

	setPath: function ( value ) {

		this.path = value;

	},

	setMaterials: function ( materials ) {

		this.materials = materials;

	},

	parse: function ( text ) {

		console.time( 'OBJLoader' );

		var objects = [];
		var object;
		var foundObjects = false;
		var vertices = [];
		var normals = [];
		var uvs = [];

		function addObject( name ) {

			var geometry = {
				vertices: [],
				normals: [],
				uvs: []
			};

			var material = {
				name: '',
				smooth: true
			};

			object = {
				name: name,
				geometry: geometry,
				material: material
			};

			objects.push( object );

		}

		function parseVertexIndex( value ) {

			var index = parseInt( value );

			return ( index >= 0 ? index - 1 : index + vertices.length / 3 ) * 3;

		}

		function parseNormalIndex( value ) {

			var index = parseInt( value );

			return ( index >= 0 ? index - 1 : index + normals.length / 3 ) * 3;

		}

		function parseUVIndex( value ) {

			var index = parseInt( value );

			return ( index >= 0 ? index - 1 : index + uvs.length / 2 ) * 2;

		}

		function addVertex( a, b, c ) {

			object.geometry.vertices.push(
				vertices[ a ], vertices[ a + 1 ], vertices[ a + 2 ],
				vertices[ b ], vertices[ b + 1 ], vertices[ b + 2 ],
				vertices[ c ], vertices[ c + 1 ], vertices[ c + 2 ]
			);

		}

		function addNormal( a, b, c ) {

			object.geometry.normals.push(
				normals[ a ], normals[ a + 1 ], normals[ a + 2 ],
				normals[ b ], normals[ b + 1 ], normals[ b + 2 ],
				normals[ c ], normals[ c + 1 ], normals[ c + 2 ]
			);

		}

		function addUV( a, b, c ) {

			object.geometry.uvs.push(
				uvs[ a ], uvs[ a + 1 ],
				uvs[ b ], uvs[ b + 1 ],
				uvs[ c ], uvs[ c + 1 ]
			);

		}

		function addFace( a, b, c, d,  ua, ub, uc, ud, na, nb, nc, nd ) {

			var ia = parseVertexIndex( a );
			var ib = parseVertexIndex( b );
			var ic = parseVertexIndex( c );
			var id;

			if ( d === undefined ) {

				addVertex( ia, ib, ic );

			} else {

				id = parseVertexIndex( d );

				addVertex( ia, ib, id );
				addVertex( ib, ic, id );

			}

			if ( ua !== undefined ) {

				ia = parseUVIndex( ua );
				ib = parseUVIndex( ub );
				ic = parseUVIndex( uc );

				if ( d === undefined ) {

					addUV( ia, ib, ic );

				} else {

					id = parseUVIndex( ud );

					addUV( ia, ib, id );
					addUV( ib, ic, id );

				}

			}

			if ( na !== undefined ) {

				ia = parseNormalIndex( na );
				ib = parseNormalIndex( nb );
				ic = parseNormalIndex( nc );

				if ( d === undefined ) {

					addNormal( ia, ib, ic );

				} else {

					id = parseNormalIndex( nd );

					addNormal( ia, ib, id );
					addNormal( ib, ic, id );

				}

			}

		}

		addObject( '' );

		//

		if ( text.indexOf('\r\n') !== -1 ) {
			// This is faster than String.split with regex that splits on both
			text = text.replace('\r\n', '\n');
		}

		var lines = text.split( '\n' );

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

			var line = lines[ i ].trim();
			if ( line.length === 0 ) {
				continue;
			}

			var lineFirstChar = line.charAt( 0 );
			if ( lineFirstChar === '#' ) {
				// @todo invoke passed in handler if any
				continue;
			}
			var lineSecondChar = line.charAt( 1 );

			var result = [];
			if ( lineFirstChar === "v" ) {
				if ( lineSecondChar === " " && ( result = this.regexp.vertex_pattern.exec( line ) ) !== null ) {

					// ["v 1.0 2.0 3.0", "1.0", "2.0", "3.0"]

					vertices.push(
						parseFloat( result[ 1 ] ),
						parseFloat( result[ 2 ] ),
						parseFloat( result[ 3 ] )
					);

				} else if ( lineSecondChar === "n" && ( result = this.regexp.normal_pattern.exec( line ) ) !== null ) {

					// ["vn 1.0 2.0 3.0", "1.0", "2.0", "3.0"]

					normals.push(
						parseFloat( result[ 1 ] ),
						parseFloat( result[ 2 ] ),
						parseFloat( result[ 3 ] )
					);

				} else if ( lineSecondChar === "t" && ( result = this.regexp.uv_pattern.exec( line ) ) !== null ) {

					// ["vt 0.1 0.2", "0.1", "0.2"]

					uvs.push(
						parseFloat( result[ 1 ] ),
						parseFloat( result[ 2 ] )
					);

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

				if ( ( result = this.regexp.face_pattern1.exec( line ) ) !== null ) {

					// ["f 1 2 3", "1", "2", "3", undefined]

					addFace(
						result[ 1 ], result[ 2 ], result[ 3 ], result[ 4 ]
					);

				} else if ( ( result = this.regexp.face_pattern2.exec( line ) ) !== null ) {

					// ["f 1/1 2/2 3/3", " 1/1", "1", "1", " 2/2", "2", "2", " 3/3", "3", "3", undefined, undefined, undefined]

					addFace(
						result[ 2 ], result[ 5 ], result[ 8 ], result[ 11 ],
						result[ 3 ], result[ 6 ], result[ 9 ], result[ 12 ]
					);

				} else if ( ( result = this.regexp.face_pattern3.exec( line ) ) !== null ) {

					// ["f 1/1/1 2/2/2 3/3/3", " 1/1/1", "1", "1", "1", " 2/2/2", "2", "2", "2", " 3/3/3", "3", "3", "3", undefined, undefined, undefined, undefined]

					addFace(
						result[ 2 ], result[ 6 ], result[ 10 ], result[ 14 ],
						result[ 3 ], result[ 7 ], result[ 11 ], result[ 15 ],
						result[ 4 ], result[ 8 ], result[ 12 ], result[ 16 ]
					);

				} else if ( ( result = this.regexp.face_pattern4.exec( line ) ) !== null ) {

					// ["f 1//1 2//2 3//3", " 1//1", "1", "1", " 2//2", "2", "2", " 3//3", "3", "3", undefined, undefined, undefined]

					addFace(
						result[ 2 ], result[ 5 ], result[ 8 ], result[ 11 ],
						undefined, undefined, undefined, undefined,
						result[ 3 ], result[ 6 ], result[ 9 ], result[ 12 ]
					);

				}
			} else if ( ( result = this.regexp.object_pattern.exec( line ) ) !== null ) {

				// o object_name
				// or
				// g group_name

				var name = result[ 0 ].substr( 1 ).trim();

				if ( foundObjects === false ) {

					foundObjects = true;
					object.name = name;

				} else {

					addObject( name );

				}

			} else if ( this.regexp.material_use_pattern.test( line ) ) {

				// material

				object.material.name = line.substring( 7 ).trim();

			} else if ( this.regexp.material_library_pattern.test( line ) ) {

				// mtl file

			} else if ( ( result = this.regexp.smoothing_pattern.exec( line ) ) !== null ) {

				// smooth shading

				object.material.smooth = result[ 1 ] === "1" || result[ 1 ] === "on";

			} else {

				throw new Error( "Unexpected line: " + line );

			}

		}

		var container = new THREE.Group();

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

			object = objects[ i ];
			var geometry = object.geometry;

			var buffergeometry = new THREE.BufferGeometry();

			buffergeometry.addAttribute( 'position', new THREE.BufferAttribute( new Float32Array( geometry.vertices ), 3 ) );

			if ( geometry.normals.length > 0 ) {

				buffergeometry.addAttribute( 'normal', new THREE.BufferAttribute( new Float32Array( geometry.normals ), 3 ) );

			} else {

				buffergeometry.computeVertexNormals();

			}

			if ( geometry.uvs.length > 0 ) {

				buffergeometry.addAttribute( 'uv', new THREE.BufferAttribute( new Float32Array( geometry.uvs ), 2 ) );

			}

			var material;

			if ( this.materials !== null ) {

				material = this.materials.create( object.material.name );

			}

			if ( !material ) {

				material = new THREE.MeshPhongMaterial();
				material.name = object.material.name;

			}

			material.shading = object.material.smooth ? THREE.SmoothShading : THREE.FlatShading;

			var mesh = new THREE.Mesh( buffergeometry, material );
			mesh.name = object.name;

			container.add( mesh );

		}

		console.timeEnd( 'OBJLoader' );

		return container;

	}

};