three
Version:
JavaScript 3D library
95 lines (58 loc) • 2.35 kB
JavaScript
/**
* @author kovacsv / http://kovacsv.hu/
* @author mrdoob / http://mrdoob.com/
* @author mudcube / http://mudcu.be/
*/
THREE.STLBinaryExporter = function () {};
THREE.STLBinaryExporter.prototype = {
constructor: THREE.STLBinaryExporter,
parse: ( function () {
var vector = new THREE.Vector3();
var normalMatrixWorld = new THREE.Matrix3();
return function parse( scene ) {
// We collect objects first, as we may need to convert from BufferGeometry to Geometry
var objects = [];
var triangles = 0;
scene.traverse( function ( object ) {
if ( ! ( object instanceof THREE.Mesh ) ) return;
var geometry = object.geometry;
if ( geometry instanceof THREE.BufferGeometry ) {
geometry = new THREE.Geometry().fromBufferGeometry( geometry );
}
if ( ! ( geometry instanceof THREE.Geometry ) ) return;
triangles += geometry.faces.length;
objects.push( {
geometry: geometry,
matrix: object.matrixWorld
} );
} );
var offset = 80; // skip header
var bufferLength = triangles * 2 + triangles * 3 * 4 * 4 + 80 + 4;
var arrayBuffer = new ArrayBuffer( bufferLength );
var output = new DataView( arrayBuffer );
output.setUint32( offset, triangles, true ); offset += 4;
// Traversing our collected objects
objects.forEach( function ( object ) {
var vertices = object.geometry.vertices;
var faces = object.geometry.faces;
normalMatrixWorld.getNormalMatrix( object.matrix );
for ( var i = 0, l = faces.length; i < l; i ++ ) {
var face = faces[ i ];
vector.copy( face.normal ).applyMatrix3( normalMatrixWorld ).normalize();
output.setFloat32( offset, vector.x, true ); offset += 4; // normal
output.setFloat32( offset, vector.y, true ); offset += 4;
output.setFloat32( offset, vector.z, true ); offset += 4;
var indices = [ face.a, face.b, face.c ];
for ( var j = 0; j < 3; j ++ ) {
vector.copy( vertices[ indices[ j ] ] ).applyMatrix4( object.matrix );
output.setFloat32( offset, vector.x, true ); offset += 4; // vertices
output.setFloat32( offset, vector.y, true ); offset += 4;
output.setFloat32( offset, vector.z, true ); offset += 4;
}
output.setUint16( offset, 0, true ); offset += 2; // attribute byte count
}
} );
return output;
};
}() )
};