1  /**
  2   * @author aleeper / http://adamleeper.com/
  3   * @author mrdoob / http://mrdoob.com/
  4   * @author gero3 / https://github.com/gero3
  5   *
  6   * Description: A THREE loader for STL ASCII files, as created by Solidworks and other CAD programs.
  7   *
  8   * Supports both binary and ASCII encoded files, with automatic detection of type.
  9   *
 10   * Limitations:
 11   *  Binary decoding supports "Magics" color format (http://en.wikipedia.org/wiki/STL_(file_format)#Color_in_binary_STL).
 12   *  There is perhaps some question as to how valid it is to always assume little-endian-ness.
 13   *  ASCII decoding assumes file is UTF-8. Seems to work for the examples...
 14   *
 15   * Usage:
 16   *  var loader = new THREE.STLLoader();
 17   *  loader.load( './models/stl/slotted_disk.stl', function ( geometry ) {
 18   *    scene.add( new THREE.Mesh( geometry ) );
 19   *  });
 20   *
 21   * For binary STLs geometry might contain colors for vertices. To use it:
 22   *  // use the same code to load STL as above
 23   *  if (geometry.hasColors) {
 24   *    material = new THREE.MeshPhongMaterial({ opacity: geometry.alpha, vertexColors: THREE.VertexColors });
 25   *  } else { .... }
 26   *  var mesh = new THREE.Mesh( geometry, material );
 27   */
 28  
 29  
 30  THREE.STLLoader = function ( manager ) {
 31  
 32  	this.manager = ( manager !== undefined ) ? manager : THREE.DefaultLoadingManager;
 33  
 34  };
 35  
 36  THREE.STLLoader.prototype = {
 37  
 38  	constructor: THREE.STLLoader,
 39  
 40  	load: function ( url, onLoad, onProgress, onError ) {
 41  
 42  		var scope = this;
 43  
 44  		var loader = new THREE.XHRLoader( scope.manager );
 45  		loader.setCrossOrigin( this.crossOrigin );
 46  		loader.setResponseType('arraybuffer');
 47  		loader.load( url, function ( text ) {
 48  
 49  			onLoad( scope.parse( text ) );
 50  
 51  		}, onProgress, onError );
 52  
 53  	},
 54  	
 55  	parse: function ( data ) {
 56  
 57  		var isBinary = function () {
 58  
 59  			var expect, face_size, n_faces, reader;
 60  			reader = new DataView( binData );
 61  			face_size = (32 / 8 * 3) + ((32 / 8 * 3) * 3) + (16 / 8);
 62  			n_faces = reader.getUint32(80, true);
 63  			expect = 80 + (32 / 8) + (n_faces * face_size);
 64  			
 65  			if ( expect === reader.byteLength ) {
 66  				
 67  				return true;
 68  				
 69  			}
 70  
 71  			// some binary files will have different size from expected,
 72  			// checking characters higher than ASCII to confirm is binary
 73  			var fileLength = reader.byteLength;
 74  			for ( var index = 0; index < fileLength; index ++ ) {
 75  
 76  				if ( reader.getUint8(index, false) > 127 ) {
 77  					
 78  					return true;
 79  					
 80  				}
 81  
 82  			}
 83  
 84  			return false;
 85  
 86  		};
 87  
 88  		var binData = this.ensureBinary( data );
 89  
 90  		return isBinary()
 91  			? this.parseBinary( binData )
 92  			: this.parseASCII( this.ensureString( data ) );
 93  
 94  	},
 95  
 96  	parseBinary: function ( data ) {
 97  
 98  		var reader = new DataView( data );
 99  		var faces = reader.getUint32( 80, true );
100  
101  		var r, g, b, hasColors = false, colors;
102  		var defaultR, defaultG, defaultB, alpha;
103  
104  		// process STL header
105  		// check for default color in header ("COLOR=rgba" sequence).
106  
107  		for ( var index = 0; index < 80 - 10; index ++ ) {
108  
109  			if ((reader.getUint32(index, false) == 0x434F4C4F /*COLO*/) &&
110  				(reader.getUint8(index + 4) == 0x52 /*'R'*/) &&
111  				(reader.getUint8(index + 5) == 0x3D /*'='*/)) {
112  
113  				hasColors = true;
114  				colors = new Float32Array( faces * 3 * 3);
115  
116  				defaultR = reader.getUint8(index + 6) / 255;
117  				defaultG = reader.getUint8(index + 7) / 255;
118  				defaultB = reader.getUint8(index + 8) / 255;
119  				alpha = reader.getUint8(index + 9) / 255;
120  			}
121  		}
122  
123  		var dataOffset = 84;
124  		var faceLength = 12 * 4 + 2;
125  
126  		var offset = 0;
127  
128  		var geometry = new THREE.BufferGeometry();
129  
130  		var vertices = new Float32Array( faces * 3 * 3 );
131  		var normals = new Float32Array( faces * 3 * 3 );
132  
133  		for ( var face = 0; face < faces; face ++ ) {
134  
135  			var start = dataOffset + face * faceLength;
136  			var normalX = reader.getFloat32(start, true);
137  			var normalY = reader.getFloat32(start + 4, true);
138  			var normalZ = reader.getFloat32(start + 8, true);
139  
140  			if (hasColors) {
141  
142  				var packedColor = reader.getUint16(start + 48, true);
143  
144  				if ((packedColor & 0x8000) === 0) { // facet has its own unique color
145  
146  					r = (packedColor & 0x1F) / 31;
147  					g = ((packedColor >> 5) & 0x1F) / 31;
148  					b = ((packedColor >> 10) & 0x1F) / 31;
149  				} else {
150  
151  					r = defaultR;
152  					g = defaultG;
153  					b = defaultB;
154  				}
155  			}
156  
157  			for ( var i = 1; i <= 3; i ++ ) {
158  
159  				var vertexstart = start + i * 12;
160  
161  				vertices[ offset     ] = reader.getFloat32( vertexstart, true );
162  				vertices[ offset + 1 ] = reader.getFloat32( vertexstart + 4, true );
163  				vertices[ offset + 2 ] = reader.getFloat32( vertexstart + 8, true );
164  
165  				normals[ offset     ] = normalX;
166  				normals[ offset + 1 ] = normalY;
167  				normals[ offset + 2 ] = normalZ;
168  
169  				if (hasColors) {
170  					colors[ offset     ] = r;
171  					colors[ offset + 1 ] = g;
172  					colors[ offset + 2 ] = b;
173  				}
174  
175  				offset += 3;
176  
177  			}
178  
179  		}
180  
181  		geometry.addAttribute( 'position', new THREE.BufferAttribute( vertices, 3 ) );
182  		geometry.addAttribute( 'normal', new THREE.BufferAttribute( normals, 3 ) );
183  
184  		if (hasColors) {
185  			geometry.addAttribute( 'color', new THREE.BufferAttribute( colors, 3 ) );
186  			geometry.hasColors = true;
187  			geometry.alpha = alpha;
188  		}
189  
190  		return geometry;
191  
192  	},
193  
194  	parseASCII: function ( data ) {
195  
196  		var geometry, length, normal, patternFace, patternNormal, patternVertex, result, text;
197  		geometry = new THREE.Geometry();
198  		patternFace = /facet([\s\S]*?)endfacet/g;
199  
200  		while ( ( result = patternFace.exec( data ) ) !== null ) {
201  
202  			text = result[0];
203  			patternNormal = /normal[\s]+([\-+]?[0-9]+\.?[0-9]*([eE][\-+]?[0-9]+)?)+[\s]+([\-+]?[0-9]*\.?[0-9]+([eE][\-+]?[0-9]+)?)+[\s]+([\-+]?[0-9]*\.?[0-9]+([eE][\-+]?[0-9]+)?)+/g;
204  
205  			while ( ( result = patternNormal.exec( text ) ) !== null ) {
206  
207  				normal = new THREE.Vector3( parseFloat( result[ 1 ] ), parseFloat( result[ 3 ] ), parseFloat( result[ 5 ] ) );
208  
209  			}
210  
211  			patternVertex = /vertex[\s]+([\-+]?[0-9]+\.?[0-9]*([eE][\-+]?[0-9]+)?)+[\s]+([\-+]?[0-9]*\.?[0-9]+([eE][\-+]?[0-9]+)?)+[\s]+([\-+]?[0-9]*\.?[0-9]+([eE][\-+]?[0-9]+)?)+/g;
212  
213  			while ( ( result = patternVertex.exec( text ) ) !== null ) {
214  
215  				geometry.vertices.push( new THREE.Vector3( parseFloat( result[ 1 ] ), parseFloat( result[ 3 ] ), parseFloat( result[ 5 ] ) ) );
216  
217  			}
218  
219  			length = geometry.vertices.length;
220  
221  			geometry.faces.push( new THREE.Face3( length - 3, length - 2, length - 1, normal ) );
222  
223  		}
224  
225  		geometry.computeBoundingBox();
226  		geometry.computeBoundingSphere();
227  
228  		return geometry;
229  
230  	},
231  
232  	ensureString: function ( buf ) {
233  
234  		if (typeof buf !== "string") {
235  			var array_buffer = new Uint8Array(buf);
236  			var str = '';
237  			for (var i = 0; i < buf.byteLength; i ++) {
238  				str += String.fromCharCode(array_buffer[i]); // implicitly assumes little-endian
239  			}
240  			return str;
241  		} else {
242  			return buf;
243  		}
244  
245  	},
246  
247  	ensureBinary: function ( buf ) {
248  
249  		if (typeof buf === "string") {
250  			var array_buffer = new Uint8Array(buf.length);
251  			for (var i = 0; i < buf.length; i ++) {
252  				array_buffer[i] = buf.charCodeAt(i) & 0xff; // implicitly assumes little-endian
253  			}
254  			return array_buffer.buffer || array_buffer;
255  		} else {
256  			return buf;
257  		}
258  		
259  	}
260  
261  };
262  
263  if ( typeof DataView === 'undefined') {
264  
265  	DataView = function(buffer, byteOffset, byteLength) {
266  
267  		this.buffer = buffer;
268  		this.byteOffset = byteOffset || 0;
269  		this.byteLength = byteLength || buffer.byteLength || buffer.length;
270  		this._isString = typeof buffer === "string";
271  
272  	}
273  
274  	DataView.prototype = {
275  
276  		_getCharCodes:function(buffer,start,length) {
277  			start = start || 0;
278  			length = length || buffer.length;
279  			var end = start + length;
280  			var codes = [];
281  			for (var i = start; i < end; i ++) {
282  				codes.push(buffer.charCodeAt(i) & 0xff);
283  			}
284  			return codes;
285  		},
286  
287  		_getBytes: function (length, byteOffset, littleEndian) {
288  
289  			var result;
290  
291  			// Handle the lack of endianness
292  			if (littleEndian === undefined) {
293  
294  				littleEndian = this._littleEndian;
295  
296  			}
297  
298  			// Handle the lack of byteOffset
299  			if (byteOffset === undefined) {
300  
301  				byteOffset = this.byteOffset;
302  
303  			} else {
304  
305  				byteOffset = this.byteOffset + byteOffset;
306  
307  			}
308  
309  			if (length === undefined) {
310  
311  				length = this.byteLength - byteOffset;
312  
313  			}
314  
315  			// Error Checking
316  			if (typeof byteOffset !== 'number') {
317  
318  				throw new TypeError('DataView byteOffset is not a number');
319  
320  			}
321  
322  			if (length < 0 || byteOffset + length > this.byteLength) {
323  
324  				throw new Error('DataView length or (byteOffset+length) value is out of bounds');
325  
326  			}
327  
328  			if (this.isString) {
329  
330  				result = this._getCharCodes(this.buffer, byteOffset, byteOffset + length);
331  
332  			} else {
333  
334  				result = this.buffer.slice(byteOffset, byteOffset + length);
335  
336  			}
337  
338  			if (!littleEndian && length > 1) {
339  
340  				if (!(result instanceof Array)) {
341  
342  					result = Array.prototype.slice.call(result);
343  
344  				}
345  
346  				result.reverse();
347  			}
348  
349  			return result;
350  
351  		},
352  
353  		// Compatibility functions on a String Buffer
354  
355  		getFloat64: function (byteOffset, littleEndian) {
356  
357  			var b = this._getBytes(8, byteOffset, littleEndian),
358  
359  				sign = 1 - (2 * (b[7] >> 7)),
360  				exponent = ((((b[7] << 1) & 0xff) << 3) | (b[6] >> 4)) - ((1 << 10) - 1),
361  
362  			// Binary operators such as | and << operate on 32 bit values, using + and Math.pow(2) instead
363  				mantissa = ((b[6] & 0x0f) * Math.pow(2, 48)) + (b[5] * Math.pow(2, 40)) + (b[4] * Math.pow(2, 32)) +
364  							(b[3] * Math.pow(2, 24)) + (b[2] * Math.pow(2, 16)) + (b[1] * Math.pow(2, 8)) + b[0];
365  
366  			if (exponent === 1024) {
367  				if (mantissa !== 0) {
368  					return NaN;
369  				} else {
370  					return sign * Infinity;
371  				}
372  			}
373  
374  			if (exponent === -1023) { // Denormalized
375  				return sign * mantissa * Math.pow(2, -1022 - 52);
376  			}
377  
378  			return sign * (1 + mantissa * Math.pow(2, -52)) * Math.pow(2, exponent);
379  
380  		},
381  
382  		getFloat32: function (byteOffset, littleEndian) {
383  
384  			var b = this._getBytes(4, byteOffset, littleEndian),
385  
386  				sign = 1 - (2 * (b[3] >> 7)),
387  				exponent = (((b[3] << 1) & 0xff) | (b[2] >> 7)) - 127,
388  				mantissa = ((b[2] & 0x7f) << 16) | (b[1] << 8) | b[0];
389  
390  			if (exponent === 128) {
391  				if (mantissa !== 0) {
392  					return NaN;
393  				} else {
394  					return sign * Infinity;
395  				}
396  			}
397  
398  			if (exponent === -127) { // Denormalized
399  				return sign * mantissa * Math.pow(2, -126 - 23);
400  			}
401  
402  			return sign * (1 + mantissa * Math.pow(2, -23)) * Math.pow(2, exponent);
403  		},
404  
405  		getInt32: function (byteOffset, littleEndian) {
406  			var b = this._getBytes(4, byteOffset, littleEndian);
407  			return (b[3] << 24) | (b[2] << 16) | (b[1] << 8) | b[0];
408  		},
409  
410  		getUint32: function (byteOffset, littleEndian) {
411  			return this.getInt32(byteOffset, littleEndian) >>> 0;
412  		},
413  
414  		getInt16: function (byteOffset, littleEndian) {
415  			return (this.getUint16(byteOffset, littleEndian) << 16) >> 16;
416  		},
417  
418  		getUint16: function (byteOffset, littleEndian) {
419  			var b = this._getBytes(2, byteOffset, littleEndian);
420  			return (b[1] << 8) | b[0];
421  		},
422  
423  		getInt8: function (byteOffset) {
424  			return (this.getUint8(byteOffset) << 24) >> 24;
425  		},
426  
427  		getUint8: function (byteOffset) {
428  			return this._getBytes(1, byteOffset)[0];
429  		}
430  
431  	 };
432  
433  }