[vtkusers] Re: vtkOBBTree vs. vtkCellLocator

[John Biddiscombe]

>(and anywyas - I think CellLocator is apparantly more effecient right?)


That depends largely on the distribution of your data. A cell locator
breaks the world into regular boxes and is therefore fast to traverse,
but if your data is lumped into a small regions with a couple of cells
miles away, then the cell locator will be inefficient. In this case an
OBB tree is a better bet. It uses adaptive subdivision of space and
althougb traversing is slightly slower, finding objects is in this case
quicker.

Note that finding closest point algorithm is easily implemented using
cellLocator as boxes can be queried in a regular manner - using a Bbtree
is more tricky as nearby points may be stored in very different branches
of the tree.

JB