toJSON( data ) {

		if ( data === undefined ) {

			console.log( 'THREE.InterleavedBufferAttribute.toJSON(): Serializing an interleaved buffer attribute will de-interleave buffer data.' );

			const array = [];

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

				const index = i * this.data.stride + this.offset;

				for ( let j = 0; j < this.itemSize; j ++ ) {

					array.push( this.data.array[ index + j ] );

				}

			}

			// de-interleave data and save it as an ordinary buffer attribute for now

			return {
				itemSize: this.itemSize,
				type: this.array.constructor.name,
				array: array,
				normalized: this.normalized
			};

		} else {

			// save as true interleaved attribute

			if ( data.interleavedBuffers === undefined ) {

				data.interleavedBuffers = {};

			}

			if ( data.interleavedBuffers[ this.data.uuid ] === undefined ) {

				data.interleavedBuffers[ this.data.uuid ] = this.data.toJSON( data );

			}

			return {
				isInterleavedBufferAttribute: true,
				itemSize: this.itemSize,
				data: this.data.uuid,
				offset: this.offset,
				normalized: this.normalized
			};

		}

	}
Serializes the buffer attribute into JSON.

If no parameter is provided, cloning an interleaved buffer attribute will de-interleave buffer data.

@param {Object} [data] - An optional value holding meta information about the serialization.
@return {Object} A JSON object representing the serialized buffer attribute.