setGeometryIdAt( instanceId, geometryId ) {

		this.validateInstanceId( instanceId );
		this.validateGeometryId( geometryId );

		this._instanceInfo[ instanceId ].geometryIndex = geometryId;

		return this;

	}
Sets the geometry ID of the instance at the given index.

@param {number} instanceId - The ID of the instance to set the geometry ID of.
@param {number} geometryId - The geometry ID to be use by the instance.
@return {BatchedMesh} A reference to this batched mesh.