i'm a computer science student and a complete beginner in GIS and stuff. i'm trying create my own web-based multi-modal journey planner as my thesis. And as it is a thesis i cant use any ready-made routing engines like graphserver or opentripplanner, etc. though i can use third party applications for data convertions, like map data into sql or KML, etc. i've done some research and this what i've learned so far.
- that i can download map data from Open Street Maps (OSM) and convert them into sql like SQLlite or postreSQL for querying. (in RTree index structures)
- that i can also convert GTFS data into sql, again for querying.
- that i can link those two data sets through stops (those loading & unloading stations for each mode of transit).
- that i should convert those two data sets into a graph then link them in order to perform multi-modal routing. (i don't know if there are other solutions)
- that i can convert the resulting route into KML so i can overlay/display them on GOOGLE MAPS or other api's, for presentation. (forgot where i read this, but i know i read about this somewhere)
My question is how can i convert an osm database into a graph data .. how can i perform routing on those graph data .. this is where i got lost, i still dont know how can i perform routing algorithms from those given data sets as input/source. i tried reading the source code of graphserver, but it did no good to me.. besides it needs to be in linux system to work, and i'm currently working on windows .. i have few understanding on java .. but if i have to, i can learn it. if it what it takes so i can grasp the steps in performing routing. (as i see .. most of the routing engine are written in java)