[OSM-talk] Can someone suggest a OSM/nearmap-based route-plotting tool

Andrew Errington a.errington at lancaster.ac.uk
Sat Jan 9 15:14:20 GMT 2010


On Thu, January 7, 2010 22:54, Steve Bennett wrote:
> On Thu, Jan 7, 2010 at 8:23 PM, Andrew Errington <
> a.errington at lancaster.ac.uk> wrote:
>
>> Just done this myself, but only for a very short route.
>>
>>
>> 1) Use JOSM
>> 2) Download the map data for area of interest
>> 3) Create a new layer
>> 4) Draw route on new layer using downloaded layer as guide.
>> 5) Export new layer as GPX
>> 6) ???
>> 7) Profit!
>>
>>
>>
> Ah, yes, that works. Well, you can actually skip 2, and just use the
> slippymap plugin with osmarender as background. Except for some reason
> it's excruciatingly slow on my machine. I'm launching josm with "java
> -Xmx1000m
> -jar ..." and  windows is only reporting 235mb used by josm, with one CPU
> running at 100%. Not sure why it takes so much CPU to download and display
> a few map tiles.
>
> Now trying Craig's suggestion - seems to work very well. What's the
> difference between the different output formats? Ie, track vs route vs
> course? It's an oregon 550, so I guess courses don't work, but what's the
>  practical difference between following a route and a track? The route
> sets up a load of waypoints and tries to route between them? I recall
> trying that once before and it only loaded the first 50 or something.

Ok, fundamentally a GPX file contains three types of data:

1) Waypoints
2) Tracks
3) Routes

Waypoints are single lat/lon points with a name.

A track is an ordered sequence of lat/lon points.  Generally this is the
result of recording a trip, and each point has a timestamp.  Think of this
as "where you've been".

A route is an ordered sequence of lat/lon points.  There are no
timestamps.  The purpose of a route is to guide you from one place to
another.  The GPS presents the next point on the route and tells you the
distance and bearing.  When you get there, the next point is presented. 
Think of this as "where you're going".

Obviously you can translate between all of these representations, but some
are more useful than others.  The most useful conversion would be track to
route, i.e. you take a trip (recorded as a track) and convert it to a
route so that someone else can follow where you went.  You can make a
bunch of waypoints from a route or track.  You can add waypoints into a
route (or make a route from a bunch of waypoints).

I don't know what a "course" is, and I haven't looked.

In summary, if you want to go somewhere with the GPS then plot the route
on your map and make a GPX file containing a "route".  Download the route
to the GPS and it should do the rest.

HTH,

Andrew





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