import { BufferAttribute, BufferGeometry, FileLoader, Float32BufferAttribute, Loader, LoaderUtils, Vector3 } from 'three'; /** * 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. * * The loader returns a non-indexed buffer geometry. * * 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. * * Usage: * const loader = new 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: true }); * } else { .... } * const mesh = new THREE.Mesh( geometry, material ); * * For ASCII STLs containing multiple solids, each solid is assigned to a different group. * Groups can be used to assign a different color by defining an array of materials with the same length of * geometry.groups and passing it to the Mesh constructor: * * const mesh = new THREE.Mesh( geometry, material ); * * For example: * * const materials = []; * const nGeometryGroups = geometry.groups.length; * * const colorMap = ...; // Some logic to index colors. * * for (let i = 0; i < nGeometryGroups; i++) { * * const material = new THREE.MeshPhongMaterial({ * color: colorMap[i], * wireframe: false * }); * * } * * materials.push(material); * const mesh = new THREE.Mesh(geometry, materials); */ class STLLoader extends Loader { constructor( manager ) { super( manager ); } load( url, onLoad, onProgress, onError ) { const scope = this; const loader = new FileLoader( this.manager ); loader.setPath( this.path ); loader.setResponseType( 'arraybuffer' ); loader.setRequestHeader( this.requestHeader ); loader.setWithCredentials( this.withCredentials ); loader.load( url, function ( text ) { try { onLoad( scope.parse( text ) ); } catch ( e ) { if ( onError ) { onError( e ); } else { console.error( e ); } scope.manager.itemError( url ); } }, onProgress, onError ); } parse( data ) { function isBinary( data ) { const reader = new DataView( data ); const face_size = ( 32 / 8 * 3 ) + ( ( 32 / 8 * 3 ) * 3 ) + ( 16 / 8 ); const n_faces = reader.getUint32( 80, true ); const expect = 80 + ( 32 / 8 ) + ( n_faces * face_size ); if ( expect === reader.byteLength ) { return true; } // An ASCII STL data must begin with 'solid ' as the first six bytes. // However, ASCII STLs lacking the SPACE after the 'd' are known to be // plentiful. So, check the first 5 bytes for 'solid'. // Several encodings, such as UTF-8, precede the text with up to 5 bytes: // https://en.wikipedia.org/wiki/Byte_order_mark#Byte_order_marks_by_encoding // Search for "solid" to start anywhere after those prefixes. // US-ASCII ordinal values for 's', 'o', 'l', 'i', 'd' const solid = [ 115, 111, 108, 105, 100 ]; for ( let off = 0; off < 5; off ++ ) { // If "solid" text is matched to the current offset, declare it to be an ASCII STL. if ( matchDataViewAt( solid, reader, off ) ) return false; } // Couldn't find "solid" text at the beginning; it is binary STL. return true; } function matchDataViewAt( query, reader, offset ) { // Check if each byte in query matches the corresponding byte from the current offset for ( let i = 0, il = query.length; i < il; i ++ ) { if ( query[ i ] !== reader.getUint8( offset + i ) ) return false; } return true; } function parseBinary( data ) { const reader = new DataView( data ); const faces = reader.getUint32( 80, true ); let r, g, b, hasColors = false, colors; let defaultR, defaultG, defaultB, alpha; // process STL header // check for default color in header ("COLOR=rgba" sequence). for ( let 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; } } const dataOffset = 84; const faceLength = 12 * 4 + 2; const geometry = new BufferGeometry(); const vertices = new Float32Array( faces * 3 * 3 ); const normals = new Float32Array( faces * 3 * 3 ); for ( let face = 0; face < faces; face ++ ) { const start = dataOffset + face * faceLength; const normalX = reader.getFloat32( start, true ); const normalY = reader.getFloat32( start + 4, true ); const normalZ = reader.getFloat32( start + 8, true ); if ( hasColors ) { const 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 ( let i = 1; i <= 3; i ++ ) { const vertexstart = start + i * 12; const componentIdx = ( face * 3 * 3 ) + ( ( i - 1 ) * 3 ); vertices[ componentIdx ] = reader.getFloat32( vertexstart, true ); vertices[ componentIdx + 1 ] = reader.getFloat32( vertexstart + 4, true ); vertices[ componentIdx + 2 ] = reader.getFloat32( vertexstart + 8, true ); normals[ componentIdx ] = normalX; normals[ componentIdx + 1 ] = normalY; normals[ componentIdx + 2 ] = normalZ; if ( hasColors ) { colors[ componentIdx ] = r; colors[ componentIdx + 1 ] = g; colors[ componentIdx + 2 ] = b; } } } geometry.setAttribute( 'position', new BufferAttribute( vertices, 3 ) ); geometry.setAttribute( 'normal', new BufferAttribute( normals, 3 ) ); if ( hasColors ) { geometry.setAttribute( 'color', new BufferAttribute( colors, 3 ) ); geometry.hasColors = true; geometry.alpha = alpha; } return geometry; } function parseASCII( data ) { const geometry = new BufferGeometry(); const patternSolid = /solid([\s\S]*?)endsolid/g; const patternFace = /facet([\s\S]*?)endfacet/g; let faceCounter = 0; const patternFloat = /[\s]+([+-]?(?:\d*)(?:\.\d*)?(?:[eE][+-]?\d+)?)/.source; const patternVertex = new RegExp( 'vertex' + patternFloat + patternFloat + patternFloat, 'g' ); const patternNormal = new RegExp( 'normal' + patternFloat + patternFloat + patternFloat, 'g' ); const vertices = []; const normals = []; const normal = new Vector3(); let result; let groupCount = 0; let startVertex = 0; let endVertex = 0; while ( ( result = patternSolid.exec( data ) ) !== null ) { startVertex = endVertex; const solid = result[ 0 ]; while ( ( result = patternFace.exec( solid ) ) !== null ) { let vertexCountPerFace = 0; let normalCountPerFace = 0; const text = result[ 0 ]; while ( ( result = patternNormal.exec( text ) ) !== null ) { normal.x = parseFloat( result[ 1 ] ); normal.y = parseFloat( result[ 2 ] ); normal.z = parseFloat( result[ 3 ] ); normalCountPerFace ++; } while ( ( result = patternVertex.exec( text ) ) !== null ) { vertices.push( parseFloat( result[ 1 ] ), parseFloat( result[ 2 ] ), parseFloat( result[ 3 ] ) ); normals.push( normal.x, normal.y, normal.z ); vertexCountPerFace ++; endVertex ++; } // every face have to own ONE valid normal if ( normalCountPerFace !== 1 ) { console.error( 'THREE.STLLoader: Something isn\'t right with the normal of face number ' + faceCounter ); } // each face have to own THREE valid vertices if ( vertexCountPerFace !== 3 ) { console.error( 'THREE.STLLoader: Something isn\'t right with the vertices of face number ' + faceCounter ); } faceCounter ++; } const start = startVertex; const count = endVertex - startVertex; geometry.addGroup( start, count, groupCount ); groupCount ++; } geometry.setAttribute( 'position', new Float32BufferAttribute( vertices, 3 ) ); geometry.setAttribute( 'normal', new Float32BufferAttribute( normals, 3 ) ); return geometry; } function ensureString( buffer ) { if ( typeof buffer !== 'string' ) { return LoaderUtils.decodeText( new Uint8Array( buffer ) ); } return buffer; } function ensureBinary( buffer ) { if ( typeof buffer === 'string' ) { const array_buffer = new Uint8Array( buffer.length ); for ( let i = 0; i < buffer.length; i ++ ) { array_buffer[ i ] = buffer.charCodeAt( i ) & 0xff; // implicitly assumes little-endian } return array_buffer.buffer || array_buffer; } else { return buffer; } } // start const binData = ensureBinary( data ); return isBinary( binData ) ? parseBinary( binData ) : parseASCII( ensureString( data ) ); } } export { STLLoader };