swap = cloneBucket; cloneBucket = cloneBackBucket; cloneBackBucket = swap;
    public void swapBuckets() {        SpatialList swap = transparentBucket;        transparentBucket = transparentBackBucket;        transparentBackBucket = swap;        swap = orthoBucket;        orthoBucket = orthoBackBucket;        orthoBackBucket = swap;        swap = opaqueBucket;        opaqueBucket = opaqueBackBucket;        opaqueBackBucket = swap;        swap = cloneBucket;        cloneBucket = cloneBackBucket;        cloneBackBucket = swap;    }