<!-- AVATAR-FORGE · part 52 -->
		this.boundingBox.expandByPoint( _vector$8 );

						_vector$8.addVectors( this.boundingBox.max, _box$2.max );
						this.boundingBox.expandByPoint( _vector$8 );

					} else {

						this.boundingBox.expandByPoint( _box$2.min );
						this.boundingBox.expandByPoint( _box$2.max );

					}

				}

			}

		} else {

			this.boundingBox.makeEmpty();

		}

		if ( isNaN( this.boundingBox.min.x ) || isNaN( this.boundingBox.min.y ) || isNaN( this.boundingBox.min.z ) ) {

			console.error( 'THREE.BufferGeometry.computeBoundingBox(): Computed min/max have NaN values. The "position" attribute is likely to have NaN values.', this );

		}

	}

	computeBoundingSphere() {

		if ( this.boundingSphere === null ) {

			this.boundingSphere = new Sphere();

		}

		const position = this.attributes.position;
		const morphAttributesPosition = this.morphAttributes.position;

		if ( position && position.isGLBufferAttribute ) {

			console.error( 'THREE.BufferGeometry.computeBoundingSphere(): GLBufferAttribute requires a manual bounding sphere.', this );

			this.boundingSphere.set( new Vector3(), Infinity );

			return;

		}

		if ( position ) {

			// first, find the center of the bounding sphere

			const center = this.boundingSphere.center;

			_box$2.setFromBufferAttribute( position );

			// process morph attributes if present

			if ( morphAttributesPosition ) {

				for ( let i = 0, il = morphAttributesPosition.length; i < il; i ++ ) {

					const morphAttribute = morphAttributesPosition[ i ];
					_boxMorphTargets.setFromBufferAttribute( morphAttribute );

					if ( this.morphTargetsRelative ) {

						_vector$8.addVectors( _box$2.min, _boxMorphTargets.min );
						_box$2.expandByPoint( _vector$8 );

						_vector$8.addVectors( _box$2.max, _boxMorphTargets.max );
						_box$2.expandByPoint( _vector$8 );

					} else {

						_box$2.expandByPoint( _boxMorphTargets.min );
						_box$2.expandByPoint( _boxMorphTargets.max );

					}

				}

			}

			_box$2.getCenter( center );

			// second, try to find a boundingSphere with a radius smaller than the
			// boundingSphere of the boundingBox: sqrt(3) smaller in the best case

			let maxRadiusSq = 0;

			for ( let i = 0, il = position.count; i < il; i ++ ) {

				_vector$8.fromBufferAttribute( position, i );

				maxRadiusSq = Math.max( maxRadiusSq, center.distanceToSquared( _vector$8 ) );

			}

			// process morph attributes if present

			if ( morphAttributesPosition ) {

				for ( let i = 0, il = morphAttributesPosition.length; i < il; i ++ ) {

					const morphAttribute = morphAttributesPosition[ i ];
					const morphTargetsRelative = this.morphTargetsRelative;

					for ( let j = 0, jl = morphAttribute.count; j < jl; j ++ ) {

						_vector$8.fromBufferAttribute( morphAttribute, j );

						if ( morphTargetsRelative ) {

							_offset.fromBufferAttribute( position, j );
							_vector$8.add( _offset );

						}

						maxRadiusSq = Math.max( maxRadiusSq, center.distanceToSquared( _vector$8 ) );

					}

				}

			}

			this.boundingSphere.radius = Math.sqrt( maxRadiusSq );

			if ( isNaN( this.boundingSphere.radius ) ) {

				console.error( 'THREE.BufferGeometry.computeBoundingSphere(): Computed radius is NaN. The "position" attribute is likely to have NaN values.', this );

			}

		}

	}

	computeTangents() {

		const index = this.index;
		const attributes = this.attributes;

		// based on http://www.terathon.com/code/tangent.html
		// (per vertex tangents)

		if ( index === null ||
			 attributes.position === undefined ||
			 attributes.normal === undefined ||
			 attributes.uv === undefined ) {

			console.error( 'THREE.BufferGeometry: .computeTangents() failed. Missing required attributes (index, position, normal or uv)' );
			return;

		}

		const positionAttribute = attributes.position;
		const normalAttribute = attributes.normal;
		const uvAttribute = attributes.uv;

		if ( this.hasAttribute( 'tangent' ) === false ) {

			this.setAttribute( 'tangent', new BufferAttribute( new Float32Array( 4 * positionAttribute.count ), 4 ) );

		}

		const tangentAttribute = this.getAttribute( 'tangent' );

		const tan1 = [], tan2 = [];

		for ( let i = 0; i < positionAttribute.count; i ++ ) {

			tan1[ i ] = new Vector3();
			tan2[ i ] = new Vector3();

		}

		const vA = new Vector3(),
			vB = new Vector3(),
			vC = new Vector3(),

			uvA = new Vector2(),
			uvB = new Vector2(),
			uvC = new Vector2(),

			sdir = new Vector3(),
			tdir = new Vector3();

		function handleTriangle( a, b, c ) {

			vA.fromBufferAttribute( positionAttribute, a );
			vB.fromBufferAttribute( positionAttribute, b );
			vC.fromBufferAttribute( positionAttribute, c );

			uvA.fromBufferAttribute( uvAttribute, a );
			uvB.fromBufferAttribute( uvAttribute, b );
			uvC.fromBufferAttribute( uvAttribute, c );

			vB.sub( vA );
			vC.sub( vA );

			uvB.sub( uvA );
			uvC.sub( uvA );

			const r = 1.0 / ( uvB.x * uvC.y - uvC.x * uvB.y );

			// silently ignore degenerate uv tri