English 中文(简体)
Algorithm for fast point lookup and line of sight traversal
原标题:

I m putting together a small library that consumes Geographic Information System (GIS) data and allows for fast point in feature, point near feature, and line of sight queries. Much of this data will consist of big areal features with enormous numbers of vertices.

An R Tree variant might work, though I wonder how those perform on the point in areal queries. I also suspect the line of sight queries would destroy most of the performance gains.

A quad tree with variable sized children is the next thing that pops to mind. That would allow linking between various child levels, perhaps, and speed the line of site queries.

Kd trees pop to mind as well, though again, the line of site queries might prove problematic.

So the question is, what algorithm would you recommend?

问题回答

Isn t this the sort of thing raytracers use octrees for?





相关问题
How to add/merge several Big O s into one

If I have an algorithm which is comprised of (let s say) three sub-algorithms, all with different O() characteristics, e.g.: algorithm A: O(n) algorithm B: O(log(n)) algorithm C: O(n log(n)) How do ...

Grokking Timsort

There s a (relatively) new sort on the block called Timsort. It s been used as Python s list.sort, and is now going to be the new Array.sort in Java 7. There s some documentation and a tiny Wikipedia ...

Manually implementing high performance algorithms in .NET

As a learning experience I recently tried implementing Quicksort with 3 way partitioning in C#. Apart from needing to add an extra range check on the left/right variables before the recursive call, ...

Print possible strings created from a Number

Given a 10 digit Telephone Number, we have to print all possible strings created from that. The mapping of the numbers is the one as exactly on a phone s keypad. i.e. for 1,0-> No Letter for 2->...

Enumerating All Minimal Directed Cycles Of A Directed Graph

I have a directed graph and my problem is to enumerate all the minimal (cycles that cannot be constructed as the union of other cycles) directed cycles of this graph. This is different from what the ...

Quick padding of a string in Delphi

I was trying to speed up a certain routine in an application, and my profiler, AQTime, identified one method in particular as a bottleneck. The method has been with us for years, and is part of a "...

热门标签