MapInfo Pro

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  • 1.  Issue with tile server that returns 404 for missing tiles / out of bounds

    Posted yesterday
    Edited by Jonas Nordlund yesterday

    Hi!

    We're currently struggling with a tile server that returns 404 Not Found for tiles that are missing / out of bounds, in this case outside of Sweden. So the tile server actually doesn't hold the entire world.

    A few tile rendering libraries or tools (like OpenLayers, Leaflet..) either simply ignore them with blank tiles or can be made to ignore those.

    However, I suspect this is the reason we get (translated by me) "An error occured while reading the Tile server table:The remote server reported an error: (404) Not found" when opening the TAB file in MapInfo Pro.

    We have confirmed the URL format is correct (LevelRowColumn style) and the accompanying XML file looks like this (domain name replaced):

    <?xml version="1.0" encoding="utf-8"?>
    <TileServerInfo Type="LevelRowColumn">
      <Url>https://tiles.example.com/tiles/{LEVEL}/{ROW}/{COL}.png</Url>
      <MinLevel>1</MinLevel>
      <MaxLevel>18</MaxLevel>
      <TileSize Height="256" Width="256" />
      <AttributionText Font="Font (&quot;Tahoma&quot;,257,8,16777215,0)"></AttributionText>
    </TileServerInfo>

    Can you confirm such tile servers would have this issue in MapInfo Pro?

    Is there a flag or something where we can dodge the issue?

    Can bounds info in the TAB file be used (or something in the XML)? But it's currently having a typical "global" projection set like this:

    Definition Table
      File "Tiles.xml"
      Type "TILESERVER"
      CoordSys Earth Projection 10, 157, "m", 0 Bounds (-20037508.342789244, -20037508.343038857) (20037508.342789244, 20037508.343038857)
    ReadOnly



    ------------------------------
    Jonas Nordlund
    Software Developer
    Norconsult AB
    Sweden
    ------------------------------



  • 2.  RE: Issue with tile server that returns 404 for missing tiles / out of bounds

    Employee
    Posted 13 hours ago

    Hey Jonas

    MapInfo Pro probably fails to load the tile server table as it fails to get a test tile returned from the server.

    We typically try with tile (0,0,0). But if your tile server has a limited extent, that tile may not exist, and so MapInfo Pro thinks the services failed.

    You can add a test tile to your Tile Server table like this:

      <TestTile>

         <Level>12</Level>

         <Row>1661</Row>

         <Column>2444</Column>

      </TestTile>

    Try if that works



    ------------------------------
    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
    ------------------------------

    Original Message


  • 3.  RE: Issue with tile server that returns 404 for missing tiles / out of bounds

    Posted 3 hours ago

    Thanks for the quick reply. This looked very promising and just what I was looking for because the tile server indeed reports 404 for the (0,0,0) tile.

    I've checked with the service license and it's open source & CC-BY-SA so if it helps, I can give you the actual server.

    The map is a snow mobile track map for Sweden which is useful both for entertaining rides, as well as the utlity sector to efficiently get to trouble with excessive snow in the power grid (poles, lines). We're looking to synergize this data with our own utlity pole documentation in MapInfo.

    Here's our Skoterleder.TAB:

    !table
    !version 1050
    !charset WindowsLatin1
     
    Definition Table
      File "Skoterleder.xml"
      Type "TILESERVER"
      CoordSys Earth Projection 10, 157, "m", 0 Bounds (-20037508.342789244, -20037508.343038857) (20037508.342789244, 20037508.343038857)
    ReadOnly
    And here's our current Skoterleder.XML:
    <?xml version="1.0" encoding="utf-8"?>
    <TileServerInfo Type="LevelRowColumn">
      <Url>https://tiles.skoterleder.org/tiles/{LEVEL}/{ROW}/{COL}.png</Url>
      <MinLevel>5</MinLevel>
      <MaxLevel>14</MaxLevel>
      <TestTile>
        <Level>5</Level>
        <Row>17</Row>
        <Column>8</Column>
      </TestTile>
      <TileSize Height="256" Width="256" />
      <AttributionText Font="Font (&quot;Tahoma&quot;,257,8,16777215,0)">© Skoterleder.org © OpenStreetMap contributors</AttributionText>
    </TileServerInfo>
    This test tile is accessible in my web browser at: https://tiles.skoterleder.org/tiles/5/17/8.png
    However, I still get the issue when opening the TAB+XML in MapInfo. :-(
    It's really puzzling to me... I set MinLevel to 5 just to be 100% sure, it had kind of "so-so" coverage on even lower zoom levels. I double checked the tiles and they are indeed 256x256 too.


    ------------------------------
    Jonas Nordlund
    Software Developer
    Norconsult AB
    Sweden
    ------------------------------

    Original Message