Use of tiled baselayers with commercial layers

[liuar]

1. create a map using tiled base layers
   
2. add a commercial layer (Google Street) to the application definition.
   
3. View the application definition in browser.
   
4. Baselayers are not displayed.
   

Wish: Baselayers should coexist with commercial layers as long as they are defined in the same zoom level.

[madair]

I was able to get this to work with the following steps:

• with Maestro, set up the tiled layer so that it has the same scale levels (finite display scales) as the google layer, if you don't specify the lowest scales, specify a zoomOffset in the layer options in AppDef.

e.g. using the set of scales:

1128.50004257674
2257.00008515349
4514.00017030697
9028.00034061395
18056.0006812279
36112.0013624558
72224.0027249116
144448.005449823
288896.010899646
577792.021799293
1155584.04359859

use a zoomOffset of 9

• with Maestro, set the coordinate system to spherical mercator:

PROJCS["WGS 84 / Pseudo-Mercator",GEOGCS["Popular Visualisation CRS",DATUM["Popular_Visualisation_Datum",SPHEROID["Popular Visualisation Sphere",6378137,0],TOWGS84[0,0,0,0,0,0,0]],PRIMEM["Greenwich",0],UNIT["degree",0.01745329251994328]],UNIT["m",1],PROJECTION["Mercator_1SP"],PARAMETER["central_meridian",0],PARAMETER["scale_factor",1],PARAMETER["false_easting",0],PARAMETER["false_northing",0],AXIS["X",EAST],AXIS["Y",NORTH]]

I had to do this in the XML editor because the WKT is not available in the drop downs

• in Fusion Mapguide layer, don't set the DPI value to 96 but use the OpenLayers default

• OpenLayers MapGuide layer is patched to support the zoomOffset property

Then using the following MapGroup in AppDef, we can get MapGuide tiled layer overlaid on the Google layer:

    <MapGroup id="ticket468">
      <InitialView>
          <MinX>-9774168</MinX>
          <MinY>5415995</MinY>
          <MaxX>-9754637</MaxX>
          <MaxY>5434757</MaxY>
      </InitialView>
      <Map>
        <Type>Google</Type>
        <Extension>
          <ResourceId>google</ResourceId>
          <Options>
            <name>GoogleLayer</name>
            <type>G_PHYSICAL_MAP</type>
            <isBaseLayer>true</isBaseLayer>
            <sphericalMercator>true</sphericalMercator>
          </Options>
        </Extension>
      </Map>
      <Map id="mg1">
        <Type>MapGuide</Type>
        <SingleTile>false</SingleTile>
        <Extension>
          <ResourceId>Library://Samples/Sheboygan/MapsTiled/SheboyganSphericalMerc.MapDefinition</ResourceId>
          <Options>
             <isBaseLayer>false</isBaseLayer>
             <useOverlay>true</useOverlay>
             <zoomOffset>9</zoomOffset>
          </Options>
        </Extension>
      </Map>
    </MapGroup>

[madair]

required changes have been committed to Fusion trunk in rev [2439]