存储用于通过x，y坐标定位的对象 [英] Storing objects for locating by x,y coordinates
问题描述
我正在尝试确定一种存储一组对象的快速方法，每个对象都有一个x和y坐标值，这样我就可以快速检索某个矩形或圆形内的所有对象。
对于小型对象集（~100），简单地将它们存储在列表中并迭代它的简单方法相对较快。但是，对于规模更大的群体来说，这预计会很慢。
我已经尝试将它们存储在一对TreeMaps中，一个在x坐标上排序，一个在y坐标上排序，使用以下代码：
I'm trying to determine a fast way of storing a set of objects, each of which have an x and y coordinate value, such that I can quickly retrieve all objects within a certain rectangle or circle. For small sets of objects (~100) the naive approach of simply storing them in a list, and iterating through it, is relatively quick. However, for much larger groups, that is expectedly slow. I've tried storing them in a pair of TreeMaps as well, one sorted on the x coordinate, and one sorted on the y coordinate, using this code:
xSubset = objectsByX.subSet( minX, maxX );
ySubset = objectsByY.subSet( minY, maxY );
result.addAll( xSubset );
result.retainAll( ySubset );
这也适用，对于较大的对象集更快，但仍然比我想要的慢。
部分问题还在于这些对象四处移动，需要插回到此存储中，这意味着将它们从树中删除并重新添加到树/列表中。
我不禁想到必须有更好的解决方案。
我在Java中实现这个，如果它有任何区别，虽然我希望任何解决方案都会以有用的模式/算法的形式出现。
This also works, and is faster for larger sets of objects, but is still slower than I would like. Part of the problem is also that these objects move around, and need to be inserted back into this storage, which means removing them from and re-adding them to the trees/lists. I can't help but think there must be better solutions out there. I'm implementing this in Java, if it makes any difference, though I expect any solution will be more in the form of a useful pattern/algorithm.
推荐答案
四叉树似乎解决了我提出的具体问题。 Kd-Trees 是一种更通用的形式，适用于任意数量的维度，而不仅仅是两个维度。
Quadtrees seem to solve the specific problem I asked. Kd-Trees are a more general form, for any number of dimensions, rather than just two.
R-Trees 可能如果存储的对象有一个边界矩形，而不仅仅是一个简单的点，也会很有用。
R-Trees may also be useful if the objects being stored have a bounding rectangle, rather than being just a simple point.
这些类型结构的通用术语是空间索引。
The general term for these type of structures is Spatial Index.
There is a Java implementation of Quadtree and R-Tree.
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