Child node in MBR (R-Tree Implementation)


I am very new to this R-Tree concept. Sorry If I ask a very basic question related to Rtree. I have read a few literature on R-Tree to get the basic concept of R-Tree. However, I could not understand the clustering or grouping steps in MBR. What’s bothering me is:

How many points or object could fit in each MBR? i could see that the number of object stored in each MBR is varies. So is there any condition or procedure or formula or anything to determine how many objects will be stored in each MBR?

Thanks for your help!

Is your R-Tree question related to openNURB, Grasshopper, or something else?