PDA

View Full Version : How to get GPS coordinates by interval on the route in mappoint



blue jay
01-15-2011, 04:32 PM
Hi,
I need help on how to predict GPS coordinates on the route in mappoint. If I have start point A and End Point B. Mappoint can find the best route AB for me. How can I get GPS coordinates by interval (every meter) on route AB. Thank a lot.
http://www.mapforums.com/images/misc/progress.gif

Wilfried
01-18-2011, 02:44 AM
Hi,

What you can do is get the coordinates from every waypoint on the route. Of course that is not every meter :(

Winwaed
01-18-2011, 07:46 AM
By distance, no you can't.
Each direction has its own location stored with it, but this is for the best view for that direction instruction - ie. there is no guarantee that it is even on the road.

The best you can do is, choose "shortest route" (NOT fastest route) and set the rest stops to be every minute. This will mess up your travel time, but the rest stops have locations. Use these for your coordinates.

Richard

blue jay
01-18-2011, 09:57 PM
Richard,

Thanks for the suggestion. I try out the method that stopped every minute on the route. The distance between points vary depends on road speed and exits (anywhere from .2 to 5 miles). In my application, I needed the route to be separated on a fixed interval. This method will not work for me.

thanks,
Terry,

Winwaed
01-19-2011, 07:50 AM
Well you can't do what you are asking,then. What is the larger application? There might be a different approach...


Richard

Mattys Consulting
01-19-2011, 12:20 PM
Actually, we have code that does this for Florida municipalities that require handicapped-access at fixed intervals along specific routes. It is tricky stuff.

Eric Frost
01-19-2011, 12:34 PM
Could you just adjust the speeds, say make everything 60 miles per hour?

Eric

blue jay
01-20-2011, 05:29 PM
I wanted to try by finding the closest point to the route. Starting by a list of points offset from the route starting point, by calculating the distances between those points to the route. The minimum distance (point that intersect with the route would be used as the next point.
This method would require the route direction. Could anybody let me know if we can find the directions on a route ?

thanks

Winwaed
01-21-2011, 08:16 AM
There are direction objects but these are text. You could, possibly use their locations (intended for viewing) as a guide, but in the general case (eg. a road that bends back on itself), I think you are going to have to widen the search space and not rely on "direction hints".

It will also be slow.

Richard