Doodle3D-Slicer/three.js-master/examples/js/loaders/BinaryLoader.js
2017-06-22 13:21:07 +02:00

753 lines
21 KiB
JavaScript
Executable File

/**
* @author alteredq / http://alteredqualia.com/
*/
THREE.BinaryLoader = function ( showStatus ) {
THREE.Loader.call( this, showStatus );
};
THREE.BinaryLoader.prototype = Object.create( THREE.Loader.prototype );
THREE.BinaryLoader.prototype.constructor = THREE.BinaryLoader;
// Load models generated by slim OBJ converter with BINARY option (converter_obj_three_slim.py -t binary)
// - binary models consist of two files: JS and BIN
// - parameters
// - url (required)
// - callback (required)
// - texturePath (optional: if not specified, textures will be assumed to be in the same folder as JS model file)
// - binaryPath (optional: if not specified, binary file will be assumed to be in the same folder as JS model file)
THREE.BinaryLoader.prototype.load = function ( url, callback, texturePath, binaryPath ) {
// todo: unify load API to for easier SceneLoader use
texturePath = texturePath || this.extractUrlBase( url );
binaryPath = binaryPath || this.extractUrlBase( url );
var callbackProgress = this.showProgress ? THREE.Loader.prototype.updateProgress : undefined;
this.onLoadStart();
// #1 load JS part via web worker
this.loadAjaxJSON( this, url, callback, texturePath, binaryPath, callbackProgress );
};
THREE.BinaryLoader.prototype.loadAjaxJSON = function ( context, url, callback, texturePath, binaryPath, callbackProgress ) {
var xhr = new XMLHttpRequest();
texturePath = texturePath && ( typeof texturePath === "string" ) ? texturePath : this.extractUrlBase( url );
binaryPath = binaryPath && ( typeof binaryPath === "string" ) ? binaryPath : this.extractUrlBase( url );
xhr.onreadystatechange = function () {
if ( xhr.readyState == 4 ) {
if ( xhr.status == 200 || xhr.status == 0 ) {
var json = JSON.parse( xhr.responseText );
context.loadAjaxBuffers( json, callback, binaryPath, texturePath, callbackProgress );
} else {
console.error( "THREE.BinaryLoader: Couldn't load [" + url + "] [" + xhr.status + "]" );
}
}
};
xhr.open( "GET", url, true );
xhr.send( null );
};
THREE.BinaryLoader.prototype.loadAjaxBuffers = function ( json, callback, binaryPath, texturePath, callbackProgress ) {
var scope = this;
var xhr = new XMLHttpRequest(),
url = binaryPath + json.buffers;
xhr.addEventListener( 'load', function ( event ) {
var buffer = xhr.response;
if ( buffer === undefined ) {
// IEWEBGL needs this
buffer = ( new Uint8Array( xhr.responseBody ) ).buffer;
}
if ( buffer.byteLength == 0 ) { // iOS and other XMLHttpRequest level 1
var buffer = new ArrayBuffer( xhr.responseText.length );
var bufView = new Uint8Array( buffer );
for ( var i = 0, l = xhr.responseText.length; i < l; i ++ ) {
bufView[ i ] = xhr.responseText.charCodeAt( i ) & 0xff;
}
}
scope.createBinModel( buffer, callback, texturePath, json.materials );
}, false );
if ( callbackProgress !== undefined ) {
xhr.addEventListener( 'progress', function ( event ) {
if ( event.lengthComputable ) {
callbackProgress( event );
}
}, false );
}
xhr.addEventListener( 'error', function ( event ) {
console.error( "THREE.BinaryLoader: Couldn't load [" + url + "] [" + xhr.status + "]" );
}, false );
xhr.open( "GET", url, true );
xhr.responseType = "arraybuffer";
if ( xhr.overrideMimeType ) xhr.overrideMimeType( "text/plain; charset=x-user-defined" );
xhr.send( null );
};
// Binary AJAX parser
THREE.BinaryLoader.prototype.createBinModel = function ( data, callback, texturePath, jsonMaterials ) {
var Model = function ( texturePath ) {
var scope = this,
currentOffset = 0,
md,
normals = [],
uvs = [],
start_tri_flat, start_tri_smooth, start_tri_flat_uv, start_tri_smooth_uv,
start_quad_flat, start_quad_smooth, start_quad_flat_uv, start_quad_smooth_uv,
tri_size, quad_size,
len_tri_flat, len_tri_smooth, len_tri_flat_uv, len_tri_smooth_uv,
len_quad_flat, len_quad_smooth, len_quad_flat_uv, len_quad_smooth_uv;
THREE.Geometry.call( this );
md = parseMetaData( data, currentOffset );
currentOffset += md.header_bytes;
/*
md.vertex_index_bytes = Uint32Array.BYTES_PER_ELEMENT;
md.material_index_bytes = Uint16Array.BYTES_PER_ELEMENT;
md.normal_index_bytes = Uint32Array.BYTES_PER_ELEMENT;
md.uv_index_bytes = Uint32Array.BYTES_PER_ELEMENT;
*/
// buffers sizes
tri_size = md.vertex_index_bytes * 3 + md.material_index_bytes;
quad_size = md.vertex_index_bytes * 4 + md.material_index_bytes;
len_tri_flat = md.ntri_flat * ( tri_size );
len_tri_smooth = md.ntri_smooth * ( tri_size + md.normal_index_bytes * 3 );
len_tri_flat_uv = md.ntri_flat_uv * ( tri_size + md.uv_index_bytes * 3 );
len_tri_smooth_uv = md.ntri_smooth_uv * ( tri_size + md.normal_index_bytes * 3 + md.uv_index_bytes * 3 );
len_quad_flat = md.nquad_flat * ( quad_size );
len_quad_smooth = md.nquad_smooth * ( quad_size + md.normal_index_bytes * 4 );
len_quad_flat_uv = md.nquad_flat_uv * ( quad_size + md.uv_index_bytes * 4 );
len_quad_smooth_uv = md.nquad_smooth_uv * ( quad_size + md.normal_index_bytes * 4 + md.uv_index_bytes * 4 );
// read buffers
currentOffset += init_vertices( currentOffset );
currentOffset += init_normals( currentOffset );
currentOffset += handlePadding( md.nnormals * 3 );
currentOffset += init_uvs( currentOffset );
start_tri_flat = currentOffset;
start_tri_smooth = start_tri_flat + len_tri_flat + handlePadding( md.ntri_flat * 2 );
start_tri_flat_uv = start_tri_smooth + len_tri_smooth + handlePadding( md.ntri_smooth * 2 );
start_tri_smooth_uv = start_tri_flat_uv + len_tri_flat_uv + handlePadding( md.ntri_flat_uv * 2 );
start_quad_flat = start_tri_smooth_uv + len_tri_smooth_uv + handlePadding( md.ntri_smooth_uv * 2 );
start_quad_smooth = start_quad_flat + len_quad_flat + handlePadding( md.nquad_flat * 2 );
start_quad_flat_uv = start_quad_smooth + len_quad_smooth + handlePadding( md.nquad_smooth * 2 );
start_quad_smooth_uv = start_quad_flat_uv + len_quad_flat_uv + handlePadding( md.nquad_flat_uv * 2 );
// have to first process faces with uvs
// so that face and uv indices match
init_triangles_flat_uv( start_tri_flat_uv );
init_triangles_smooth_uv( start_tri_smooth_uv );
init_quads_flat_uv( start_quad_flat_uv );
init_quads_smooth_uv( start_quad_smooth_uv );
// now we can process untextured faces
init_triangles_flat( start_tri_flat );
init_triangles_smooth( start_tri_smooth );
init_quads_flat( start_quad_flat );
init_quads_smooth( start_quad_smooth );
this.computeFaceNormals();
function handlePadding( n ) {
return ( n % 4 ) ? ( 4 - n % 4 ) : 0;
};
function parseMetaData( data, offset ) {
var metaData = {
'signature' :parseString( data, offset, 12 ),
'header_bytes' :parseUChar8( data, offset + 12 ),
'vertex_coordinate_bytes' :parseUChar8( data, offset + 13 ),
'normal_coordinate_bytes' :parseUChar8( data, offset + 14 ),
'uv_coordinate_bytes' :parseUChar8( data, offset + 15 ),
'vertex_index_bytes' :parseUChar8( data, offset + 16 ),
'normal_index_bytes' :parseUChar8( data, offset + 17 ),
'uv_index_bytes' :parseUChar8( data, offset + 18 ),
'material_index_bytes' :parseUChar8( data, offset + 19 ),
'nvertices' :parseUInt32( data, offset + 20 ),
'nnormals' :parseUInt32( data, offset + 20 + 4 * 1 ),
'nuvs' :parseUInt32( data, offset + 20 + 4 * 2 ),
'ntri_flat' :parseUInt32( data, offset + 20 + 4 * 3 ),
'ntri_smooth' :parseUInt32( data, offset + 20 + 4 * 4 ),
'ntri_flat_uv' :parseUInt32( data, offset + 20 + 4 * 5 ),
'ntri_smooth_uv' :parseUInt32( data, offset + 20 + 4 * 6 ),
'nquad_flat' :parseUInt32( data, offset + 20 + 4 * 7 ),
'nquad_smooth' :parseUInt32( data, offset + 20 + 4 * 8 ),
'nquad_flat_uv' :parseUInt32( data, offset + 20 + 4 * 9 ),
'nquad_smooth_uv' :parseUInt32( data, offset + 20 + 4 * 10 )
};
/*
console.log( "signature: " + metaData.signature );
console.log( "header_bytes: " + metaData.header_bytes );
console.log( "vertex_coordinate_bytes: " + metaData.vertex_coordinate_bytes );
console.log( "normal_coordinate_bytes: " + metaData.normal_coordinate_bytes );
console.log( "uv_coordinate_bytes: " + metaData.uv_coordinate_bytes );
console.log( "vertex_index_bytes: " + metaData.vertex_index_bytes );
console.log( "normal_index_bytes: " + metaData.normal_index_bytes );
console.log( "uv_index_bytes: " + metaData.uv_index_bytes );
console.log( "material_index_bytes: " + metaData.material_index_bytes );
console.log( "nvertices: " + metaData.nvertices );
console.log( "nnormals: " + metaData.nnormals );
console.log( "nuvs: " + metaData.nuvs );
console.log( "ntri_flat: " + metaData.ntri_flat );
console.log( "ntri_smooth: " + metaData.ntri_smooth );
console.log( "ntri_flat_uv: " + metaData.ntri_flat_uv );
console.log( "ntri_smooth_uv: " + metaData.ntri_smooth_uv );
console.log( "nquad_flat: " + metaData.nquad_flat );
console.log( "nquad_smooth: " + metaData.nquad_smooth );
console.log( "nquad_flat_uv: " + metaData.nquad_flat_uv );
console.log( "nquad_smooth_uv: " + metaData.nquad_smooth_uv );
var total = metaData.header_bytes
+ metaData.nvertices * metaData.vertex_coordinate_bytes * 3
+ metaData.nnormals * metaData.normal_coordinate_bytes * 3
+ metaData.nuvs * metaData.uv_coordinate_bytes * 2
+ metaData.ntri_flat * ( metaData.vertex_index_bytes*3 + metaData.material_index_bytes )
+ metaData.ntri_smooth * ( metaData.vertex_index_bytes*3 + metaData.material_index_bytes + metaData.normal_index_bytes*3 )
+ metaData.ntri_flat_uv * ( metaData.vertex_index_bytes*3 + metaData.material_index_bytes + metaData.uv_index_bytes*3 )
+ metaData.ntri_smooth_uv * ( metaData.vertex_index_bytes*3 + metaData.material_index_bytes + metaData.normal_index_bytes*3 + metaData.uv_index_bytes*3 )
+ metaData.nquad_flat * ( metaData.vertex_index_bytes*4 + metaData.material_index_bytes )
+ metaData.nquad_smooth * ( metaData.vertex_index_bytes*4 + metaData.material_index_bytes + metaData.normal_index_bytes*4 )
+ metaData.nquad_flat_uv * ( metaData.vertex_index_bytes*4 + metaData.material_index_bytes + metaData.uv_index_bytes*4 )
+ metaData.nquad_smooth_uv * ( metaData.vertex_index_bytes*4 + metaData.material_index_bytes + metaData.normal_index_bytes*4 + metaData.uv_index_bytes*4 );
console.log( "total bytes: " + total );
*/
return metaData;
};
function parseString( data, offset, length ) {
var charArray = new Uint8Array( data, offset, length );
var text = "";
for ( var i = 0; i < length; i ++ ) {
text += String.fromCharCode( charArray[ offset + i ] );
}
return text;
};
function parseUChar8( data, offset ) {
var charArray = new Uint8Array( data, offset, 1 );
return charArray[ 0 ];
};
function parseUInt32( data, offset ) {
var intArray = new Uint32Array( data, offset, 1 );
return intArray[ 0 ];
};
function init_vertices( start ) {
var nElements = md.nvertices;
var coordArray = new Float32Array( data, start, nElements * 3 );
var i, x, y, z;
for ( i = 0; i < nElements; i ++ ) {
x = coordArray[ i * 3 ];
y = coordArray[ i * 3 + 1 ];
z = coordArray[ i * 3 + 2 ];
scope.vertices.push( new THREE.Vector3( x, y, z ) );
}
return nElements * 3 * Float32Array.BYTES_PER_ELEMENT;
};
function init_normals( start ) {
var nElements = md.nnormals;
if ( nElements ) {
var normalArray = new Int8Array( data, start, nElements * 3 );
var i, x, y, z;
for ( i = 0; i < nElements; i ++ ) {
x = normalArray[ i * 3 ];
y = normalArray[ i * 3 + 1 ];
z = normalArray[ i * 3 + 2 ];
normals.push( x / 127, y / 127, z / 127 );
}
}
return nElements * 3 * Int8Array.BYTES_PER_ELEMENT;
};
function init_uvs( start ) {
var nElements = md.nuvs;
if ( nElements ) {
var uvArray = new Float32Array( data, start, nElements * 2 );
var i, u, v;
for ( i = 0; i < nElements; i ++ ) {
u = uvArray[ i * 2 ];
v = uvArray[ i * 2 + 1 ];
uvs.push( u, v );
}
}
return nElements * 2 * Float32Array.BYTES_PER_ELEMENT;
};
function init_uvs3( nElements, offset ) {
var i, uva, uvb, uvc, u1, u2, u3, v1, v2, v3;
var uvIndexBuffer = new Uint32Array( data, offset, 3 * nElements );
for ( i = 0; i < nElements; i ++ ) {
uva = uvIndexBuffer[ i * 3 ];
uvb = uvIndexBuffer[ i * 3 + 1 ];
uvc = uvIndexBuffer[ i * 3 + 2 ];
u1 = uvs[ uva * 2 ];
v1 = uvs[ uva * 2 + 1 ];
u2 = uvs[ uvb * 2 ];
v2 = uvs[ uvb * 2 + 1 ];
u3 = uvs[ uvc * 2 ];
v3 = uvs[ uvc * 2 + 1 ];
scope.faceVertexUvs[ 0 ].push( [
new THREE.Vector2( u1, v1 ),
new THREE.Vector2( u2, v2 ),
new THREE.Vector2( u3, v3 )
] );
}
};
function init_uvs4( nElements, offset ) {
var i, uva, uvb, uvc, uvd, u1, u2, u3, u4, v1, v2, v3, v4;
var uvIndexBuffer = new Uint32Array( data, offset, 4 * nElements );
for ( i = 0; i < nElements; i ++ ) {
uva = uvIndexBuffer[ i * 4 ];
uvb = uvIndexBuffer[ i * 4 + 1 ];
uvc = uvIndexBuffer[ i * 4 + 2 ];
uvd = uvIndexBuffer[ i * 4 + 3 ];
u1 = uvs[ uva * 2 ];
v1 = uvs[ uva * 2 + 1 ];
u2 = uvs[ uvb * 2 ];
v2 = uvs[ uvb * 2 + 1 ];
u3 = uvs[ uvc * 2 ];
v3 = uvs[ uvc * 2 + 1 ];
u4 = uvs[ uvd * 2 ];
v4 = uvs[ uvd * 2 + 1 ];
scope.faceVertexUvs[ 0 ].push( [
new THREE.Vector2( u1, v1 ),
new THREE.Vector2( u2, v2 ),
new THREE.Vector2( u4, v4 )
] );
scope.faceVertexUvs[ 0 ].push( [
new THREE.Vector2( u2, v2 ),
new THREE.Vector2( u3, v3 ),
new THREE.Vector2( u4, v4 )
] );
}
};
function init_faces3_flat( nElements, offsetVertices, offsetMaterials ) {
var i, a, b, c, m;
var vertexIndexBuffer = new Uint32Array( data, offsetVertices, 3 * nElements );
var materialIndexBuffer = new Uint16Array( data, offsetMaterials, nElements );
for ( i = 0; i < nElements; i ++ ) {
a = vertexIndexBuffer[ i * 3 ];
b = vertexIndexBuffer[ i * 3 + 1 ];
c = vertexIndexBuffer[ i * 3 + 2 ];
m = materialIndexBuffer[ i ];
scope.faces.push( new THREE.Face3( a, b, c, null, null, m ) );
}
};
function init_faces4_flat( nElements, offsetVertices, offsetMaterials ) {
var i, a, b, c, d, m;
var vertexIndexBuffer = new Uint32Array( data, offsetVertices, 4 * nElements );
var materialIndexBuffer = new Uint16Array( data, offsetMaterials, nElements );
for ( i = 0; i < nElements; i ++ ) {
a = vertexIndexBuffer[ i * 4 ];
b = vertexIndexBuffer[ i * 4 + 1 ];
c = vertexIndexBuffer[ i * 4 + 2 ];
d = vertexIndexBuffer[ i * 4 + 3 ];
m = materialIndexBuffer[ i ];
scope.faces.push( new THREE.Face3( a, b, d, null, null, m ) );
scope.faces.push( new THREE.Face3( b, c, d, null, null, m ) );
}
};
function init_faces3_smooth( nElements, offsetVertices, offsetNormals, offsetMaterials ) {
var i, a, b, c, m;
var na, nb, nc;
var vertexIndexBuffer = new Uint32Array( data, offsetVertices, 3 * nElements );
var normalIndexBuffer = new Uint32Array( data, offsetNormals, 3 * nElements );
var materialIndexBuffer = new Uint16Array( data, offsetMaterials, nElements );
for ( i = 0; i < nElements; i ++ ) {
a = vertexIndexBuffer[ i * 3 ];
b = vertexIndexBuffer[ i * 3 + 1 ];
c = vertexIndexBuffer[ i * 3 + 2 ];
na = normalIndexBuffer[ i * 3 ];
nb = normalIndexBuffer[ i * 3 + 1 ];
nc = normalIndexBuffer[ i * 3 + 2 ];
m = materialIndexBuffer[ i ];
var nax = normals[ na * 3 ],
nay = normals[ na * 3 + 1 ],
naz = normals[ na * 3 + 2 ],
nbx = normals[ nb * 3 ],
nby = normals[ nb * 3 + 1 ],
nbz = normals[ nb * 3 + 2 ],
ncx = normals[ nc * 3 ],
ncy = normals[ nc * 3 + 1 ],
ncz = normals[ nc * 3 + 2 ];
scope.faces.push( new THREE.Face3( a, b, c, [
new THREE.Vector3( nax, nay, naz ),
new THREE.Vector3( nbx, nby, nbz ),
new THREE.Vector3( ncx, ncy, ncz )
], null, m ) );
}
};
function init_faces4_smooth( nElements, offsetVertices, offsetNormals, offsetMaterials ) {
var i, a, b, c, d, m;
var na, nb, nc, nd;
var vertexIndexBuffer = new Uint32Array( data, offsetVertices, 4 * nElements );
var normalIndexBuffer = new Uint32Array( data, offsetNormals, 4 * nElements );
var materialIndexBuffer = new Uint16Array( data, offsetMaterials, nElements );
for ( i = 0; i < nElements; i ++ ) {
a = vertexIndexBuffer[ i * 4 ];
b = vertexIndexBuffer[ i * 4 + 1 ];
c = vertexIndexBuffer[ i * 4 + 2 ];
d = vertexIndexBuffer[ i * 4 + 3 ];
na = normalIndexBuffer[ i * 4 ];
nb = normalIndexBuffer[ i * 4 + 1 ];
nc = normalIndexBuffer[ i * 4 + 2 ];
nd = normalIndexBuffer[ i * 4 + 3 ];
m = materialIndexBuffer[ i ];
var nax = normals[ na * 3 ],
nay = normals[ na * 3 + 1 ],
naz = normals[ na * 3 + 2 ],
nbx = normals[ nb * 3 ],
nby = normals[ nb * 3 + 1 ],
nbz = normals[ nb * 3 + 2 ],
ncx = normals[ nc * 3 ],
ncy = normals[ nc * 3 + 1 ],
ncz = normals[ nc * 3 + 2 ],
ndx = normals[ nd * 3 ],
ndy = normals[ nd * 3 + 1 ],
ndz = normals[ nd * 3 + 2 ];
scope.faces.push( new THREE.Face3( a, b, d, [
new THREE.Vector3( nax, nay, naz ),
new THREE.Vector3( nbx, nby, nbz ),
new THREE.Vector3( ndx, ndy, ndz )
], null, m ) );
scope.faces.push( new THREE.Face3( b, c, d, [
new THREE.Vector3( nbx, nby, nbz ),
new THREE.Vector3( ncx, ncy, ncz ),
new THREE.Vector3( ndx, ndy, ndz )
], null, m ) );
}
};
function init_triangles_flat( start ) {
var nElements = md.ntri_flat;
if ( nElements ) {
var offsetMaterials = start + nElements * Uint32Array.BYTES_PER_ELEMENT * 3;
init_faces3_flat( nElements, start, offsetMaterials );
}
};
function init_triangles_flat_uv( start ) {
var nElements = md.ntri_flat_uv;
if ( nElements ) {
var offsetUvs = start + nElements * Uint32Array.BYTES_PER_ELEMENT * 3;
var offsetMaterials = offsetUvs + nElements * Uint32Array.BYTES_PER_ELEMENT * 3;
init_faces3_flat( nElements, start, offsetMaterials );
init_uvs3( nElements, offsetUvs );
}
};
function init_triangles_smooth( start ) {
var nElements = md.ntri_smooth;
if ( nElements ) {
var offsetNormals = start + nElements * Uint32Array.BYTES_PER_ELEMENT * 3;
var offsetMaterials = offsetNormals + nElements * Uint32Array.BYTES_PER_ELEMENT * 3;
init_faces3_smooth( nElements, start, offsetNormals, offsetMaterials );
}
};
function init_triangles_smooth_uv( start ) {
var nElements = md.ntri_smooth_uv;
if ( nElements ) {
var offsetNormals = start + nElements * Uint32Array.BYTES_PER_ELEMENT * 3;
var offsetUvs = offsetNormals + nElements * Uint32Array.BYTES_PER_ELEMENT * 3;
var offsetMaterials = offsetUvs + nElements * Uint32Array.BYTES_PER_ELEMENT * 3;
init_faces3_smooth( nElements, start, offsetNormals, offsetMaterials );
init_uvs3( nElements, offsetUvs );
}
};
function init_quads_flat( start ) {
var nElements = md.nquad_flat;
if ( nElements ) {
var offsetMaterials = start + nElements * Uint32Array.BYTES_PER_ELEMENT * 4;
init_faces4_flat( nElements, start, offsetMaterials );
}
};
function init_quads_flat_uv( start ) {
var nElements = md.nquad_flat_uv;
if ( nElements ) {
var offsetUvs = start + nElements * Uint32Array.BYTES_PER_ELEMENT * 4;
var offsetMaterials = offsetUvs + nElements * Uint32Array.BYTES_PER_ELEMENT * 4;
init_faces4_flat( nElements, start, offsetMaterials );
init_uvs4( nElements, offsetUvs );
}
};
function init_quads_smooth( start ) {
var nElements = md.nquad_smooth;
if ( nElements ) {
var offsetNormals = start + nElements * Uint32Array.BYTES_PER_ELEMENT * 4;
var offsetMaterials = offsetNormals + nElements * Uint32Array.BYTES_PER_ELEMENT * 4;
init_faces4_smooth( nElements, start, offsetNormals, offsetMaterials );
}
};
function init_quads_smooth_uv( start ) {
var nElements = md.nquad_smooth_uv;
if ( nElements ) {
var offsetNormals = start + nElements * Uint32Array.BYTES_PER_ELEMENT * 4;
var offsetUvs = offsetNormals + nElements * Uint32Array.BYTES_PER_ELEMENT * 4;
var offsetMaterials = offsetUvs + nElements * Uint32Array.BYTES_PER_ELEMENT * 4;
init_faces4_smooth( nElements, start, offsetNormals, offsetMaterials );
init_uvs4( nElements, offsetUvs );
}
};
};
Model.prototype = Object.create( THREE.Geometry.prototype );
Model.prototype.constructor = Model;
var geometry = new Model( texturePath );
var materials = this.initMaterials( jsonMaterials, texturePath );
if ( this.needsTangents( materials ) ) geometry.computeTangents();
callback( geometry, materials );
};