[Routing] How to Establish Road Hierarchy

[Nic Roets]

On Wed, Dec 12, 2012 at 3:00 AM, David Piepgrass
<dpiepgrass at mentoreng.com>wrote:

> My point, based on personal experience, is that a CH implementation could
> have some flaw that is very hard to track down. I got my algorithm to work
> perfectly (i.e. optimal routes), and I implemented stall-on-demand,
> topological sorting and other optimizations, but still it was too slow.
>
> > Very unlikely that A* beats CH in general.
> It certainly doesn't.
>
>
A* is just so much more flexible. For example, you can add a new vehicle
type without any significant penalty in terms of preprocessing. Or avoid
traffic jams that change frequently. And the flexibility can result in
significant savings on fuel and time.

Furthermore, as computers get cheaper and devices get faster, the
difference in speed between A* and CH is becoming insignificant.

All these tradeoffs are firmly in favour of A* for most applications.
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