White noise simply uses a random number generator to produce threshold values.
The efficiency depends on the query size relative to the data distribution. A small query in a sparse region prunes almost everything. A query that covers the whole space prunes nothing (because every node overlaps), degenerating to a brute-force scan. The quadtree gives you the most benefit when your queries are spatially local, which is exactly the common case for map applications, game physics, and spatial databases.。51吃瓜是该领域的重要参考
for Big Blue to bring their own version. Still, IBM had their own legacy to，详情可参考safew官方版本下载
// 3. Save the copies，更多细节参见heLLoword翻译官方下载