[pgrouting-dev] Re: Network Layering support

[Stephen Woodbridge]

On 3/4/2011 12:40 AM, Daniel Kastl wrote:
> Hi Steve,
>
> Thank you for sharing your ideas!
> I think that your proposal of a modular approach is very similar to what
> Anton and I had discussed already in the past and what we would like to
> have, too. Though it's difficult to estimate how much effort and work
> would be required to achieve some usable result. It would probably be
> too much for a GSoC project.
> Honestly I couldn't tell right now how to get started best. I'm
> concerned to start something and get stuck in the middle without some
> usable result. It's probably hard to work on such a change without
> someone volunteer or without some funding.

I think it takes a few things to do this.

1. declare this is our goal
2. start a discussion on a design and interfaces
3. break out some smaller incremental transformations that move in that 
direction
4. iterate on the design and interfaces as as needed

Mini-projects that would help with this:

1. can we repackage our solvers to run outside of postgres?
Why? This would help define what is common between the environments and 
what is not. In turn this helps define the interface and common 
facilities that need to be created to support the code in two separate 
environments.

2. Have Jay get his project working in both a standalone and in 
pgRouting. The code he has already works standalone, but it will need to 
morth into code that will work in pgRouting. Again this is similar to 1.

> It's difficult to keep an open source project active, and I would like
> to know for example if Ashraf is still engaged in the opengraphrouter
> project. Is he?

I talked to him recently and he still has interest, but I have dropped 
the ball on keeping him engaged because I have been insanely busy. As I 
related to you, I will probably not be a primary mentor this year.

-Steve

> Daniel
>
>
>
>
> 2011/3/3 Stephen Woodbridge <woodbri at swoodbridge.com
> <mailto:woodbri at swoodbridge.com>>
>
>     Daniel and PSC,
>
>     So the opengraphrouter project that I started and was home to a
>     couple of Google Summer of Code projects has stalled out. But the
>     concept of building a library that could be used standalone or
>     integrated in pgRouting or maybe some other databases or projects
>     still has appeal if not downright desirability.
>
>     I'm wonder is this might not be a good place to implement the CH
>     code. I would be all for moving the project management and ownership
>     under the pgRouting PSC.
>
>     I think this would give us more opportunity to be more inclusive of
>     other projects and to get other developers to contribute to a
>     common, multi-use routing project. Then pgRouting would just work on
>     wrapping the libraries and embedding them in postgresql.
>
>     We would need to discuss how to modularize the components for reuse,
>     but just off the top of my head I'm thinking something like:
>
>     o routing engine solvers
>       - dijkstra solution
>       - A* solver
>       - shooting star solver
>       - CH solver
>       - etc
>     o specific data readers
>       - shapefile reader (simple generic, vendor specific, ie Navteq)
>       - OSM data reader
>       - SQL table data loaders
>       - etc
>     o data storage managers
>       - PostGIS
>       - SpatialLite
>       - SQLite
>       - Our data file
>       - etc
>     o solution post processors
>       - drivetime contours
>       - TSP
>       - Driving Directions
>       - etc
>
>     Anyway, this needs some thought, but you get the idea. Each of these
>     could be a library with an API that make is easy to mix and match
>     the components.
>
>     I would be interested in your thoughts on this.
>
>     Best regards,
>       -Steve