sort( customOpaqueSort, customTransparentSort ) {

		if ( this.opaque.length > 1 ) this.opaque.sort( customOpaqueSort || painterSortStable );
		if ( this.transparentDoublePass.length > 1 ) this.transparentDoublePass.sort( customTransparentSort || reversePainterSortStable );
		if ( this.transparent.length > 1 ) this.transparent.sort( customTransparentSort || reversePainterSortStable );

	}
Sorts the internal render lists.

@param {?function(any, any): number} customOpaqueSort - A custom sort function for opaque objects.
@param {?function(any, any): number} customTransparentSort -  A custom sort function for transparent objects.