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OpenStreetMapLayer Data and Update Frequency and Tile Caching

#1

Hello,

We are using an OpenStreetMapLayer and server-side tile caching in our project. I have a couple of questions.

  1. The OpenStreetMapLayer uses OpenStreetMap data. I know in the past that ThinkGeo offered OpenStreetMap data in shapefile form that you had compiled and that you do not offer that service currently. Is the data that the OpenStreetMapLayer uses coming directly from OpenStreetMap’s servers or is it first compiled by ThinkGeo in some form and then hosted on ThinkGeo’s servers? I just want to make sure I understand whose servers are providing the map data and if it is being compile in some form first.

  2. I know that the OpenStreetMap data gets updated. What is the frequency of this update? We are caching the OpenStreetMapLayer along with our shapefile base layers to improve performance, and we need to figure out a business policy for clearing out the tile cache periodically in order to allow it to repopulate with newer data.

#2

Hi Michael,

  1. The map data is provided by the OpenStreetMap’s servers, we use those data by the form of tile image, the tile request will be creating by our MapSuite OpenStreetMapLayer class in server side, and we cut and splice the tile image to satisfy the bounding box of our tile. You can view the URI through the following code snippets:

    OpenStreetMapLayer osmMapLayer = new OpenStreetMapLayer();
osmMapLayer.SentWebRequest += OsmMapLayer_SentWebRequest;

private void OsmMapLayer_SentWebRequest(object sender, SentWebRequestEventArgs e)
{
    var uri = e.Response.ResponseUri;
}

  2. Because of point 1, the frequency of the update depends on OpenStreetMap servers, sorry i did not found the accurate information about it, and I guess here are two points to note:

    A. Please refer to http://planet.openstreetmap.org/ and the website shows the update of OSM data. But it is not the updated information of OpenStreetMap servers.
    B. It seems that the data updates are frequent, because they are based on global scope, and the data of one region is not updated frequently.

Any questions please let us know.
Thanks,
Emil

#3

Thank you for the information Emil.

#4

Hi Michael,

We are glad to hear that’s helpful.

Regards,

Don