Hi everyone , I'm developing an indoor positioning system for my college as an Android app without using GPS or wifi (just accelerometer & compass) , I'm really new to this but I started by trying to figure out how to generate a map for the building. I began by understanding the concepts of OSM (nodes, routes , closed ways , ect ,ect ..). Having finished the basic concepts of OSM , mapping is still kind of vague. I heard words like "tiles", "slippy tiles" , "rendering" , "vector data map" , so I'm little confused. So , what should be done after generating the .xml file using JOSM representing my map and how to use it ? If someone could give me some advise or some steps/terms that I should know , then I would be greatful.

asked 02 Sep '12, 13:19

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aur
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Assuming that you are able to determine accurate position within the building based on accelerometer and compass:

What you have in josm is map data (vector). By rendering it becomes raster map (picture). For practical reasons the big map is split in multiple smaller pictures (tiles). Slippy tiles would mean that you can move the map without reloading all the tiles. (easier, way more storage space, no routing) Alternatively you could do the rendering on the fly directly from vector data (not that xml, some transformation needed). This would be vector map. (more CPU intensive, less storage, more flexible).

There are two options you can choose:
1. map and actual position are displayed, user is expected to find his way based on this. 2. nr.1 + user is given directions to reach the destination

For option 1 you would just display correctly aligned raster tiles and some mark for current position. If it is only limited to your college, you could use Maperitive to do the rendering and only concentrate on determining the position and displaying correct pieces of map around it.

Option 2 is not so easy to be described here.

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answered 03 Sep '12, 00:43

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LM_1
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accept rate: 10%

pretty nice explanation .. also I found a related article : http://goo.gl/a4WnY . we're trying to achieve sth like FootPath project : http://goo.gl/li2Fh so I think we would choose option 2 , just to make sure that I understood right : we should convert the generated .osm file into a vector map (for less storage) , and process that map according to the project ? any correction or additional info would be great

(03 Sep '12, 06:03) aur

If the building as a lot on steel or high current cables the compass in the smart phone or will be affected.

(03 Sep '12, 12:16) andy mackey

@andy mackey this is a considerable issue :) but right now we're trying to figure out how could we do the mapping right

(03 Sep '12, 13:25) aur
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question asked: 02 Sep '12, 13:19

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last updated: 03 Sep '12, 13:25

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