ftn-stl-viewer
Version:
A component for viewing an STL object from a given URL by utilizing Three.js
377 lines (303 loc) • 11.7 kB
JavaScript
'use strict';
var THREE = require('three');
//
// STL Loader added
//
/**
* @author aleeper / http://adamleeper.com/
* @author mrdoob / http://mrdoob.com/
* @author gero3 / https://github.com/gero3
*
* Description: A THREE loader for STL ASCII files, as created by Solidworks and other CAD programs.
*
* Supports both binary and ASCII encoded files, with automatic detection of type.
*
* Limitations:
* Binary decoding supports "Magics" color format (http://en.wikipedia.org/wiki/STL_(file_format)#Color_in_binary_STL).
* There is perhaps some question as to how valid it is to always assume little-endian-ness.
* ASCII decoding assumes file is UTF-8. Seems to work for the examples...
*
* Usage:
* var loader = new THREE.STLLoader();
* loader.load( './models/stl/slotted_disk.stl', function ( geometry ) {
* scene.add( new THREE.Mesh( geometry ) );
* });
*
* For binary STLs geometry might contain colors for vertices. To use it:
* // use the same code to load STL as above
* if (geometry.hasColors) {
* material = new THREE.MeshPhongMaterial({ opacity: geometry.alpha, vertexColors: THREE.VertexColors });
* } else { .... }
* var mesh = new THREE.Mesh( geometry, material );
*/
THREE.STLLoader = function (manager) {
this.manager = manager !== undefined ? manager : THREE.DefaultLoadingManager;
};
THREE.STLLoader.prototype = {
constructor: THREE.STLLoader,
loadFromUrl: function loadFromUrl(url, onLoad, onProgress, onError) {
var scope = this;
var loader = new THREE.XHRLoader(scope.manager);
loader.setCrossOrigin(this.crossOrigin);
loader.setResponseType('arraybuffer');
loader.load(url, function (text) {
onLoad(scope.parse(text));
}, onProgress, onError);
},
loadFromFile: function loadFromFile(buffer, onLoad) {
var scope = this;
onLoad(scope.parse(buffer));
},
parse: function parse(data) {
var isBinary = function isBinary() {
var expect, face_size, n_faces, reader;
reader = new DataView(binData);
face_size = 32 / 8 * 3 + 32 / 8 * 3 * 3 + 16 / 8;
n_faces = reader.getUint32(80, true);
expect = 80 + 32 / 8 + n_faces * face_size;
if (expect === reader.byteLength) {
return true;
}
// some binary files will have different size from expected,
// checking characters higher than ASCII to confirm is binary
var fileLength = reader.byteLength;
for (var index = 0; index < fileLength; index++) {
if (reader.getUint8(index, false) > 127) {
return true;
}
}
return false;
};
var binData = this.ensureBinary(data);
return isBinary() ? this.parseBinary(binData) : this.parseASCII(this.ensureString(data));
},
parseBinary: function parseBinary(data) {
var reader = new DataView(data);
var faces = reader.getUint32(80, true);
var r,
g,
b,
hasColors = false,
colors;
var defaultR, defaultG, defaultB, alpha;
// process STL header
// check for default color in header ("COLOR=rgba" sequence).
for (var index = 0; index < 80 - 10; index++) {
if (reader.getUint32(index, false) == 0x434f4c4f /*COLO*/ && reader.getUint8(index + 4) == 0x52 /*'R'*/ && reader.getUint8(index + 5) == 0x3d /*'='*/
) {
hasColors = true;
colors = new Float32Array(faces * 3 * 3);
defaultR = reader.getUint8(index + 6) / 255;
defaultG = reader.getUint8(index + 7) / 255;
defaultB = reader.getUint8(index + 8) / 255;
alpha = reader.getUint8(index + 9) / 255;
}
}
var dataOffset = 84;
var faceLength = 12 * 4 + 2;
var offset = 0;
var geometry = new THREE.BufferGeometry();
var vertices = new Float32Array(faces * 3 * 3);
var normals = new Float32Array(faces * 3 * 3);
for (var face = 0; face < faces; face++) {
var start = dataOffset + face * faceLength;
var normalX = reader.getFloat32(start, true);
var normalY = reader.getFloat32(start + 4, true);
var normalZ = reader.getFloat32(start + 8, true);
if (hasColors) {
var packedColor = reader.getUint16(start + 48, true);
if ((packedColor & 0x8000) === 0) {
// facet has its own unique color
r = (packedColor & 0x1f) / 31;
g = (packedColor >> 5 & 0x1f) / 31;
b = (packedColor >> 10 & 0x1f) / 31;
} else {
r = defaultR;
g = defaultG;
b = defaultB;
}
}
for (var i = 1; i <= 3; i++) {
var vertexstart = start + i * 12;
vertices[offset] = reader.getFloat32(vertexstart, true);
vertices[offset + 1] = reader.getFloat32(vertexstart + 4, true);
vertices[offset + 2] = reader.getFloat32(vertexstart + 8, true);
normals[offset] = normalX;
normals[offset + 1] = normalY;
normals[offset + 2] = normalZ;
if (hasColors) {
colors[offset] = r;
colors[offset + 1] = g;
colors[offset + 2] = b;
}
offset += 3;
}
}
geometry.addAttribute('position', new THREE.BufferAttribute(vertices, 3));
geometry.addAttribute('normal', new THREE.BufferAttribute(normals, 3));
if (hasColors) {
geometry.addAttribute('color', new THREE.BufferAttribute(colors, 3));
geometry.hasColors = true;
geometry.alpha = alpha;
}
return geometry;
},
parseASCII: function parseASCII(data) {
var geometry, length, normal, patternFace, patternNormal, patternVertex, result, text;
geometry = new THREE.Geometry();
patternFace = /facet([\s\S]*?)endfacet/g;
while ((result = patternFace.exec(data)) !== null) {
text = result[0];
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;
while ((result = patternNormal.exec(text)) !== null) {
normal = new THREE.Vector3(parseFloat(result[1]), parseFloat(result[3]), parseFloat(result[5]));
}
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;
while ((result = patternVertex.exec(text)) !== null) {
geometry.vertices.push(new THREE.Vector3(parseFloat(result[1]), parseFloat(result[3]), parseFloat(result[5])));
}
length = geometry.vertices.length;
geometry.faces.push(new THREE.Face3(length - 3, length - 2, length - 1, normal));
}
geometry.computeBoundingBox();
geometry.computeBoundingSphere();
return geometry;
},
ensureString: function ensureString(buf) {
if (typeof buf !== 'string') {
var array_buffer = new Uint8Array(buf);
var str = '';
for (var i = 0; i < buf.byteLength; i++) {
str += String.fromCharCode(array_buffer[i]); // implicitly assumes little-endian
}
return str;
} else {
return buf;
}
},
ensureBinary: function ensureBinary(buf) {
if (typeof buf === 'string') {
var array_buffer = new Uint8Array(buf.length);
for (var i = 0; i < buf.length; i++) {
array_buffer[i] = buf.charCodeAt(i) & 0xff; // implicitly assumes little-endian
}
return array_buffer.buffer || array_buffer;
} else {
return buf;
}
}
};
if (typeof DataView === 'undefined') {
DataView = function DataView(buffer, byteOffset, byteLength) {
this.buffer = buffer;
this.byteOffset = byteOffset || 0;
this.byteLength = byteLength || buffer.byteLength || buffer.length;
this._isString = typeof buffer === 'string';
};
DataView.prototype = {
_getCharCodes: function _getCharCodes(buffer, start, length) {
start = start || 0;
length = length || buffer.length;
var end = start + length;
var codes = [];
for (var i = start; i < end; i++) {
codes.push(buffer.charCodeAt(i) & 0xff);
}
return codes;
},
_getBytes: function _getBytes(length, byteOffset, littleEndian) {
var result;
// Handle the lack of endianness
if (littleEndian === undefined) {
littleEndian = this._littleEndian;
}
// Handle the lack of byteOffset
if (byteOffset === undefined) {
byteOffset = this.byteOffset;
} else {
byteOffset = this.byteOffset + byteOffset;
}
if (length === undefined) {
length = this.byteLength - byteOffset;
}
// Error Checking
if (typeof byteOffset !== 'number') {
throw new TypeError('DataView byteOffset is not a number');
}
if (length < 0 || byteOffset + length > this.byteLength) {
throw new Error('DataView length or (byteOffset+length) value is out of bounds');
}
if (this.isString) {
result = this._getCharCodes(this.buffer, byteOffset, byteOffset + length);
} else {
result = this.buffer.slice(byteOffset, byteOffset + length);
}
if (!littleEndian && length > 1) {
if (!(result instanceof Array)) {
result = Array.prototype.slice.call(result);
}
result.reverse();
}
return result;
},
// Compatibility functions on a String Buffer
getFloat64: function getFloat64(byteOffset, littleEndian) {
var b = this._getBytes(8, byteOffset, littleEndian),
sign = 1 - 2 * (b[7] >> 7),
exponent = ((b[7] << 1 & 0xff) << 3 | b[6] >> 4) - ((1 << 10) - 1),
// Binary operators such as | and << operate on 32 bit values, using + and Math.pow(2) instead
mantissa = (b[6] & 0x0f) * Math.pow(2, 48) + b[5] * Math.pow(2, 40) + b[4] * Math.pow(2, 32) + b[3] * Math.pow(2, 24) + b[2] * Math.pow(2, 16) + b[1] * Math.pow(2, 8) + b[0];
if (exponent === 1024) {
if (mantissa !== 0) {
return NaN;
} else {
return sign * Infinity;
}
}
if (exponent === -1023) {
// Denormalized
return sign * mantissa * Math.pow(2, -1022 - 52);
}
return sign * (1 + mantissa * Math.pow(2, -52)) * Math.pow(2, exponent);
},
getFloat32: function getFloat32(byteOffset, littleEndian) {
var b = this._getBytes(4, byteOffset, littleEndian),
sign = 1 - 2 * (b[3] >> 7),
exponent = (b[3] << 1 & 0xff | b[2] >> 7) - 127,
mantissa = (b[2] & 0x7f) << 16 | b[1] << 8 | b[0];
if (exponent === 128) {
if (mantissa !== 0) {
return NaN;
} else {
return sign * Infinity;
}
}
if (exponent === -127) {
// Denormalized
return sign * mantissa * Math.pow(2, -126 - 23);
}
return sign * (1 + mantissa * Math.pow(2, -23)) * Math.pow(2, exponent);
},
getInt32: function getInt32(byteOffset, littleEndian) {
var b = this._getBytes(4, byteOffset, littleEndian);
return b[3] << 24 | b[2] << 16 | b[1] << 8 | b[0];
},
getUint32: function getUint32(byteOffset, littleEndian) {
return this.getInt32(byteOffset, littleEndian) >>> 0;
},
getInt16: function getInt16(byteOffset, littleEndian) {
return this.getUint16(byteOffset, littleEndian) << 16 >> 16;
},
getUint16: function getUint16(byteOffset, littleEndian) {
var b = this._getBytes(2, byteOffset, littleEndian);
return b[1] << 8 | b[0];
},
getInt8: function getInt8(byteOffset) {
return this.getUint8(byteOffset) << 24 >> 24;
},
getUint8: function getUint8(byteOffset) {
return this._getBytes(1, byteOffset)[0];
}
};
}
module.exports = THREE;