logic.txt

移动对象空间数据库中索引r树源码,能在eclipse下直接运行.

Least Enlargement:
   The idea is to find a rectangle that needs to be least enlarged in order to
accommodate the given rectangle. Enlargement in the sense that the sides of the
rectangle is so increased that the given rectangle is encapsulated in this 
rectangle. If the given rectangle is already in the encapsulating rectangle then 
no enlargement is required in the encapsulating rectangle as the given rectangle
is already in this rectangle.
   To do so, we find area of the MBR for the two rectangles. Then remove the
area of the encapsulating rect. from the MBR area and select the least area
MBR.

spliNode:
	This function splits a node into two. What happens here is that two new 
nodes are created. And the elements of the original node are distributed among the
two new nodes. The first new node so created is still pointed by the parent element
of the original node but the parent MBR is not adjusted(this is done in adjustTree).
The second node is not pointed by any element, that has to be again taken care
of at 'adjustTree'. Though both the new nodes themselves point to the original
node's parent.
        (feb 2003) This method now also takes the slot nodes's index, provided it has one.
If this tree is not grown from a tree node, i.e a normal RTree, pass this parameter as NOT_DEFINED.
If in case this is seeded tree then pass the this tree's (one tree out of the forest) slot node.