Hi.

Im a mappoint and vb newbie.

I have a problem.......Im trying to make a program that reads in gps coordinates from a text file and plots them as push pins on mappoint. I got that working. But when i plotted the points they're appreaing on the side of the rode on the map when they should be on the road?....does anyone know how i can correct this.....ie. making the points appear on the road and not beside it.

Thanks
Omair

What kind of scale are we talking about?

If you zoom in, the pushpins should "appear" to move away from the road (in an on-screen distance) - what is the measured distance (feet/metres) between the pins and the road?
Is the distance and the direction of the displacement consistent?

Some possibilities:

- an error in the road positioning in MapPoint's database
- your GPS is set to use a geoid other than WGS84
- rounding
- you're using MapPoint 2002 Europe and your GPS is reporting OSGR coordinates


Richard

First of all Thanks!!!! I really appreciate the prompt reply.

My GPS Reciver settings (I'm using a Garmen 18 PC) is set to use the WGS 84 by default. Furthermore im using Mappoint 2004 North America.

I forgot to mention when im plottting the point the map is at maximum zoom (1 km) and the distance between the roads and the points seem to be on average 10 m away. When i measured the distance from the points that were just on the side of ther road to the road, the measurement tool would not give me a distance. Is there a funtion in the MapPoint Active X control that i can use in a vb program to correcct this?

Thanks again.
Omair

Could this be rounding in the coordinates reported by the GPS?

10m is very good - most roads are quite a bit wider than that!

Also, I suspect you're getting close to MapPoint's internal resolution - this might be why it wouldn't let you measure the distance.


Richard

One thing i've noticed is that the coordinates for the road in Mappoint seem to be 79.53551 W while the coordinates that i have from the GPS reciver have the longitude as 79.53534. It seems as though the latitude coordinates from mappoint match up perfectly with the GPS Latitude coordinates, but the longitude coordinates are a bit off?....i've started searching for a way to correct this.

Omair

For the record, the error is about 0.6 arc-seconds.


Richard

Does mappoint have arc correction?