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GLTFExporter.js
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/**
* @author fernandojsg / http://fernandojsg.com
*/
//------------------------------------------------------------------------------
// GLTF Exporter
//------------------------------------------------------------------------------
THREE.GLTFExporter = function () {};
THREE.GLTFExporter.prototype = {
constructor: THREE.GLTFExporter,
/**
* Parse scenes and generate GLTF output
* @param {THREE.Scene or [THREE.Scenes]} input THREE.Scene or Array of THREE.Scenes
* @param {Function} onDone Callback on completed
* @param {Object} options options
* trs: Exports position, rotation and scale instead of matrix
* binary: Exports `.glb` as ArrayBuffer, instead of `.gltf` as JSON
*/
parse: function ( input, onDone, options ) {
var DEFAULT_OPTIONS = {
trs: false,
onlyVisible: true,
truncateDrawRange: true
};
options = Object.assign( {}, DEFAULT_OPTIONS, options );
var outputJSON = {
asset: {
version: "2.0",
generator: "THREE.GLTFExporter"
}
};
var byteOffset = 0;
var dataViews = [];
var cachedData = {
images: {},
materials: {}
};
/**
* Compare two arrays
*/
/**
* Compare two arrays
* @param {Array} array1 Array 1 to compare
* @param {Array} array2 Array 2 to compare
* @return {Boolean} Returns true if both arrays are equal
*/
function equalArray( array1, array2 ) {
return ( array1.length === array2.length ) && array1.every( function ( element, index ) {
return element === array2[ index ];
} );
}
/**
* Converts a string to an ArrayBuffer.
* @param {string} text
* @return {ArrayBuffer}
*/
function stringToArrayBuffer( text ) {
if ( window.TextEncoder !== undefined ) {
return new TextEncoder().encode( text ).buffer;
}
var buffer = new ArrayBuffer( text.length * 2 ); // 2 bytes per character.
var bufferView = new Uint16Array( buffer );
for ( var i = 0; i < text.length; ++ i ) {
bufferView[ i ] = text.charCodeAt( i );
}
return buffer;
}
/**
* Get the min and he max vectors from the given attribute
* @param {THREE.WebGLAttribute} attribute Attribute to find the min/max
* @return {Object} Object containing the `min` and `max` values (As an array of attribute.itemSize components)
*/
function getMinMax( attribute ) {
var output = {
min: new Array( attribute.itemSize ).fill( Number.POSITIVE_INFINITY ),
max: new Array( attribute.itemSize ).fill( Number.NEGATIVE_INFINITY )
};
for ( var i = 0; i < attribute.count; i ++ ) {
for ( var a = 0; a < attribute.itemSize; a ++ ) {
var value = attribute.array[ i * attribute.itemSize + a ];
output.min[ a ] = Math.min( output.min[ a ], value );
output.max[ a ] = Math.max( output.max[ a ], value );
}
}
return output;
}
/**
* Process a buffer to append to the default one.
* @param {THREE.BufferAttribute} attribute Attribute to store
* @param {Integer} componentType Component type (Unsigned short, unsigned int or float)
* @return {Integer} Index of the buffer created (Currently always 0)
*/
function processBuffer( attribute, componentType, start, count ) {
if ( ! outputJSON.buffers ) {
outputJSON.buffers = [
{
byteLength: 0,
uri: ''
}
];
}
var offset = 0;
var componentSize = componentType === THREE.WebGLConstants.UNSIGNED_SHORT ? 2 : 4;
// Create a new dataview and dump the attribute's array into it
var byteLength = count * attribute.itemSize * componentSize;
var dataView = new DataView( new ArrayBuffer( byteLength ) );
for ( var i = start; i < start + count; i ++ ) {
for ( var a = 0; a < attribute.itemSize; a ++ ) {
var value = attribute.array[ i * attribute.itemSize + a ];
if ( componentType === THREE.WebGLConstants.FLOAT ) {
dataView.setFloat32( offset, value, true );
} else if ( componentType === THREE.WebGLConstants.UNSIGNED_INT ) {
dataView.setUint8( offset, value, true );
} else if ( componentType === THREE.WebGLConstants.UNSIGNED_SHORT ) {
dataView.setUint16( offset, value, true );
}
offset += componentSize;
}
}
// We just use one buffer
dataViews.push( dataView );
// Always using just one buffer
return 0;
}
/**
* Process and generate a BufferView
* @param {[type]} data [description]
* @return {[type]} [description]
*/
function processBufferView( data, componentType, start, count ) {
var isVertexAttributes = componentType === THREE.WebGLConstants.FLOAT;
if ( ! outputJSON.bufferViews ) {
outputJSON.bufferViews = [];
}
var componentSize = componentType === THREE.WebGLConstants.UNSIGNED_SHORT ? 2 : 4;
// Create a new dataview and dump the attribute's array into it
var byteLength = count * data.itemSize * componentSize;
var gltfBufferView = {
buffer: processBuffer( data, componentType, start, count ),
byteOffset: byteOffset,
byteLength: byteLength,
byteStride: data.itemSize * componentSize,
target: isVertexAttributes ? THREE.WebGLConstants.ARRAY_BUFFER : THREE.WebGLConstants.ELEMENT_ARRAY_BUFFER
};
byteOffset += byteLength;
outputJSON.bufferViews.push( gltfBufferView );
// @TODO Ideally we'll have just two bufferviews: 0 is for vertex attributes, 1 for indices
var output = {
id: outputJSON.bufferViews.length - 1,
byteLength: 0
};
return output;
}
/**
* Process attribute to generate an accessor
* @param {THREE.WebGLAttribute} attribute Attribute to process
* @return {Integer} Index of the processed accessor on the "accessors" array
*/
function processAccessor( attribute, geometry ) {
if ( ! outputJSON.accessors ) {
outputJSON.accessors = [];
}
var types = [
'SCALAR',
'VEC2',
'VEC3',
'VEC4'
];
var componentType;
// Detect the component type of the attribute array (float, uint or ushort)
if ( attribute.array.constructor === Float32Array ) {
componentType = THREE.WebGLConstants.FLOAT;
} else if ( attribute.array.constructor === Uint32Array ) {
componentType = THREE.WebGLConstants.UNSIGNED_INT;
} else if ( attribute.array.constructor === Uint16Array ) {
componentType = THREE.WebGLConstants.UNSIGNED_SHORT;
} else {
throw new Error( 'THREE.GLTFExporter: Unsupported bufferAttribute component type.' );
}
var minMax = getMinMax( attribute );
var start = 0;
var count = attribute.count;
// @TODO Indexed buffer geometry with drawRange not supported yet
if ( options.truncateDrawRange && geometry.index === null ) {
start = geometry.drawRange.start;
count = geometry.drawRange.count !== Infinity ? geometry.drawRange.count : attribute.count;
}
var bufferView = processBufferView( attribute, componentType, start, count );
var gltfAccessor = {
bufferView: bufferView.id,
byteOffset: bufferView.byteOffset,
componentType: componentType,
count: count,
max: minMax.max,
min: minMax.min,
type: types[ attribute.itemSize - 1 ]
};
outputJSON.accessors.push( gltfAccessor );
return outputJSON.accessors.length - 1;
}
/**
* Process image
* @param {Texture} map Texture to process
* @return {Integer} Index of the processed texture in the "images" array
*/
function processImage( map ) {
if ( cachedData.images[ map.uuid ] ) {
return cachedData.images[ map.uuid ];
}
if ( ! outputJSON.images ) {
outputJSON.images = [];
}
var gltfImage = {};
if ( options.embedImages ) {
// @TODO { bufferView, mimeType }
} else {
// @TODO base64 based on options
gltfImage.uri = map.image.src;
}
outputJSON.images.push( gltfImage );
var index = outputJSON.images.length - 1;
cachedData.images[ map.uuid ] = index;
return index;
}
/**
* Process sampler
* @param {Texture} map Texture to process
* @return {Integer} Index of the processed texture in the "samplers" array
*/
function processSampler( map ) {
if ( ! outputJSON.samplers ) {
outputJSON.samplers = [];
}
var gltfSampler = {
magFilter: THREE.WebGLUtils.toGL( map.magFilter ),
minFilter: THREE.WebGLUtils.toGL( map.minFilter ),
wrapS: THREE.WebGLUtils.toGL( map.wrapS ),
wrapT: THREE.WebGLUtils.toGL( map.wrapT)
};
outputJSON.samplers.push( gltfSampler );
return outputJSON.samplers.length - 1;
}
/**
* Process texture
* @param {Texture} map Map to process
* @return {Integer} Index of the processed texture in the "textures" array
*/
function processTexture( map ) {
if ( ! outputJSON.textures ) {
outputJSON.textures = [];
}
var gltfTexture = {
sampler: processSampler( map ),
source: processImage( map )
};
outputJSON.textures.push( gltfTexture );
return outputJSON.textures.length - 1;
}
/**
* Process material
* @param {THREE.Material} material Material to process
* @return {Integer} Index of the processed material in the "materials" array
*/
function processMaterial( material ) {
if ( cachedData.materials[ material.uuid ] ) {
return cachedData.materials[ material.uuid ];
}
if ( ! outputJSON.materials ) {
outputJSON.materials = [];
}
if ( material instanceof THREE.ShaderMaterial ) {
console.warn( 'GLTFExporter: THREE.ShaderMaterial not supported.' );
return null;
}
if ( ! ( material instanceof THREE.MeshStandardMaterial ) ) {
console.warn( 'GLTFExporter: Currently just THREE.StandardMaterial is supported. Material conversion may lose information.' );
}
// @QUESTION Should we avoid including any attribute that has the default value?
var gltfMaterial = {
pbrMetallicRoughness: {}
};
// pbrMetallicRoughness.baseColorFactor
var color = material.color.toArray().concat( [ material.opacity ] );
if ( ! equalArray( color, [ 1, 1, 1, 1 ] ) ) {
gltfMaterial.pbrMetallicRoughness.baseColorFactor = color;
}
if ( material instanceof THREE.MeshStandardMaterial ) {
gltfMaterial.pbrMetallicRoughness.metallicFactor = material.metalness;
gltfMaterial.pbrMetallicRoughness.roughnessFactor = material.roughness;
} else {
gltfMaterial.pbrMetallicRoughness.metallicFactor = 0.5;
gltfMaterial.pbrMetallicRoughness.roughnessFactor = 0.5;
}
// pbrMetallicRoughness.baseColorTexture
if ( material.map ) {
gltfMaterial.pbrMetallicRoughness.baseColorTexture = {
index: processTexture( material.map )
};
}
if ( material instanceof THREE.MeshBasicMaterial ||
material instanceof THREE.LineBasicMaterial ||
material instanceof THREE.PointsMaterial ) {
} else {
// emissiveFactor
var emissive = material.emissive.clone().multiplyScalar( material.emissiveIntensity ).toArray();
if ( ! equalArray( emissive, [ 0, 0, 0 ] ) ) {
gltfMaterial.emissiveFactor = emissive;
}
// emissiveTexture
if ( material.emissiveMap ) {
gltfMaterial.emissiveTexture = {
index: processTexture( material.emissiveMap )
};
}
}
// normalTexture
if ( material.normalMap ) {
gltfMaterial.normalTexture = {
index: processTexture( material.normalMap )
};
if ( material.normalScale.x !== - 1 ) {
if ( material.normalScale.x !== material.normalScale.y ) {
console.warn( 'THREE.GLTFExporter: Normal scale components are different, ignoring Y and exporting X.' );
}
gltfMaterial.normalTexture.scale = material.normalScale.x;
}
}
// occlusionTexture
if ( material.aoMap ) {
gltfMaterial.occlusionTexture = {
index: processTexture( material.aoMap )
};
if ( material.aoMapIntensity !== 1.0 ) {
gltfMaterial.occlusionTexture.strength = material.aoMapIntensity;
}
}
// alphaMode
if ( material.transparent ) {
gltfMaterial.alphaMode = 'MASK'; // @FIXME We should detect MASK or BLEND
if ( material.alphaTest !== 0.5 ) {
gltfMaterial.alphaCutoff = material.alphaTest;
}
}
// doubleSided
if ( material.side === THREE.DoubleSide ) {
gltfMaterial.doubleSided = true;
}
if ( material.name ) {
gltfMaterial.name = material.name;
}
outputJSON.materials.push( gltfMaterial );
var index = outputJSON.materials.length - 1;
cachedData.materials[ material.uuid ] = index;
return index;
}
/**
* Process mesh
* @param {THREE.Mesh} mesh Mesh to process
* @return {Integer} Index of the processed mesh in the "meshes" array
*/
function processMesh( mesh ) {
if ( ! outputJSON.meshes ) {
outputJSON.meshes = [];
}
var geometry = mesh.geometry;
var mode;
// Use the correct mode
if ( mesh instanceof THREE.LineSegments ) {
mode = THREE.WebGLConstants.LINES;
} else if ( mesh instanceof THREE.LineLoop ) {
mode = THREE.WebGLConstants.LINE_LOOP;
} else if ( mesh instanceof THREE.Line ) {
mode = THREE.WebGLConstants.LINE_STRIP;
} else if ( mesh instanceof THREE.Points ) {
mode = THREE.WebGLConstants.POINTS;
} else {
if ( ! geometry.isBufferGeometry ) {
var geometryTemp = new THREE.BufferGeometry();
geometryTemp.fromGeometry( geometry );
geometry = geometryTemp;
}
if ( mesh.drawMode === THREE.TriangleFanDrawMode ) {
console.warn( 'GLTFExporter: TriangleFanDrawMode and wireframe incompatible.' );
mode = THREE.WebGLConstants.TRIANGLE_FAN;
} else if ( mesh.drawMode === THREE.TriangleStripDrawMode ) {
mode = mesh.material.wireframe ? THREE.WebGLConstants.LINE_STRIP : THREE.WebGLConstants.TRIANGLE_STRIP;
} else {
mode = mesh.material.wireframe ? THREE.WebGLConstants.LINES : THREE.WebGLConstants.TRIANGLES;
}
}
var gltfMesh = {
primitives: [
{
mode: mode,
attributes: {},
}
]
};
var material = processMaterial( mesh.material );
if ( material !== null ) {
gltfMesh.primitives[ 0 ].material = material;
}
if ( geometry.index ) {
gltfMesh.primitives[ 0 ].indices = processAccessor( geometry.index, geometry );
}
// We've just one primitive per mesh
var gltfAttributes = gltfMesh.primitives[ 0 ].attributes;
// Conversion between attributes names in threejs and gltf spec
var nameConversion = {
uv: 'TEXCOORD_0',
uv2: 'TEXCOORD_1',
color: 'COLOR_0',
skinWeight: 'WEIGHTS_0',
skinIndex: 'JOINTS_0'
};
// @QUESTION Detect if .vertexColors = THREE.VertexColors?
// For every attribute create an accessor
for ( var attributeName in geometry.attributes ) {
var attribute = geometry.attributes[ attributeName ];
attributeName = nameConversion[ attributeName ] || attributeName.toUpperCase();
gltfAttributes[ attributeName ] = processAccessor( attribute, geometry );
}
outputJSON.meshes.push( gltfMesh );
return outputJSON.meshes.length - 1;
}
/**
* Process camera
* @param {THREE.Camera} camera Camera to process
* @return {Integer} Index of the processed mesh in the "camera" array
*/
function processCamera( camera ) {
if ( ! outputJSON.cameras ) {
outputJSON.cameras = [];
}
var isOrtho = camera instanceof THREE.OrthographicCamera;
var gltfCamera = {
type: isOrtho ? 'orthographic' : 'perspective'
};
if ( isOrtho ) {
gltfCamera.orthographic = {
xmag: camera.right * 2,
ymag: camera.top * 2,
zfar: camera.far,
znear: camera.near
};
} else {
gltfCamera.perspective = {
aspectRatio: camera.aspect,
yfov: THREE.Math.degToRad( camera.fov ) / camera.aspect,
zfar: camera.far,
znear: camera.near
};
}
if ( camera.name ) {
gltfCamera.name = camera.type;
}
outputJSON.cameras.push( gltfCamera );
return outputJSON.cameras.length - 1;
}
/**
* Process Object3D node
* @param {THREE.Object3D} node Object3D to processNode
* @return {Integer} Index of the node in the nodes list
*/
function processNode( object ) {
if ( object instanceof THREE.Light ) {
console.warn( 'GLTFExporter: Unsupported node type:', object.constructor.name );
return null;
}
if ( ! outputJSON.nodes ) {
outputJSON.nodes = [];
}
var gltfNode = {};
if ( options.trs ) {
var rotation = object.quaternion.toArray();
var position = object.position.toArray();
var scale = object.scale.toArray();
if ( ! equalArray( rotation, [ 0, 0, 0, 1 ] ) ) {
gltfNode.rotation = rotation;
}
if ( ! equalArray( position, [ 0, 0, 0 ] ) ) {
gltfNode.position = position;
}
if ( ! equalArray( scale, [ 1, 1, 1 ] ) ) {
gltfNode.scale = scale;
}
} else {
object.updateMatrix();
if ( ! equalArray( object.matrix.elements, [ 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1 ] ) ) {
gltfNode.matrix = object.matrix.elements;
}
}
if ( object.name ) {
gltfNode.name = object.name;
}
if ( object.userData && Object.keys( object.userData ).length > 0 ) {
try {
gltfNode.extras = JSON.parse( JSON.stringify( object.userData ) );
} catch ( e ) {
throw new Error( 'THREE.GLTFExporter: userData can\'t be serialized' );
}
}
if ( object instanceof THREE.Mesh ||
object instanceof THREE.Line ||
object instanceof THREE.Points ) {
gltfNode.mesh = processMesh( object );
} else if ( object instanceof THREE.Camera ) {
gltfNode.camera = processCamera( object );
}
if ( object.children.length > 0 ) {
var children = [];
for ( var i = 0, l = object.children.length; i < l; i ++ ) {
var child = object.children[ i ];
if ( child.visible || options.onlyVisible === false ) {
var node = processNode( child );
if ( node !== null ) {
children.push( node );
}
}
}
if ( children.length > 0 ) {
gltfNode.children = children;
}
}
outputJSON.nodes.push( gltfNode );
return outputJSON.nodes.length - 1;
}
/**
* Process Scene
* @param {THREE.Scene} node Scene to process
*/
function processScene( scene ) {
if ( ! outputJSON.scenes ) {
outputJSON.scenes = [];
outputJSON.scene = 0;
}
var gltfScene = {
nodes: []
};
if ( scene.name ) {
gltfScene.name = scene.name;
}
outputJSON.scenes.push( gltfScene );
var nodes = [];
for ( var i = 0, l = scene.children.length; i < l; i ++ ) {
var child = scene.children[ i ];
if ( child.visible || options.onlyVisible === false ) {
var node = processNode( child );
if ( node !== null ) {
nodes.push( node );
}
}
}
if ( nodes.length > 0 ) {
gltfScene.nodes = nodes;
}
}
/**
* Creates a THREE.Scene to hold a list of objects and parse it
* @param {Array} objects List of objects to process
*/
function processObjects( objects ) {
var scene = new THREE.Scene();
scene.name = 'AuxScene';
for ( var i = 0; i < objects.length; i ++ ) {
// We push directly to children instead of calling `add` to prevent
// modify the .parent and break its original scene and hierarchy
scene.children.push( objects[ i ] );
}
processScene( scene );
}
function processInput( input ) {
input = input instanceof Array ? input : [ input ];
var objectsWithoutScene = [];
for ( var i = 0; i < input.length; i ++ ) {
if ( input[ i ] instanceof THREE.Scene ) {
processScene( input[ i ] );
} else {
objectsWithoutScene.push( input[ i ] );
}
}
if ( objectsWithoutScene.length > 0 ) {
processObjects( objectsWithoutScene );
}
}
processInput( input );
// Generate buffer
// Create a new blob with all the dataviews from the buffers
var blob = new Blob( dataViews, { type: 'application/octet-stream' } );
// Update the bytlength of the only main buffer and update the uri with the base64 representation of it
if ( outputJSON.buffers && outputJSON.buffers.length > 0 ) {
outputJSON.buffers[ 0 ].byteLength = blob.size;
var reader = new window.FileReader();
if ( options.binary === true ) {