[mapserver-users] Mapcache tileset only shows sporadically in KML / Google Earth

[John D. Evans]

Hello,

Not sure my earlier query made it to the list.

I'm using MapCache to serve for some satellite image products. It sort 
of works: the tms and wmts browsers at /mapcache/demo show full coverage 
of my data area, and let users zoom in to see full resolution image 
mosaics. But the KML superoverlay (my reason for using MapCache) only 
displays in Google Earth when I'm zoomed very far out (so that the 
entire globe is not much bigger than a golf ball on my screen). If I 
zoom in, the image usually disappears; though sometimes when zoomed in I 
do see [only] the right (east) half of my tileset, at a very low resolution.

Do you see anything wrong with my mapcache.xml (below)?
Is there anything else I should be checking?

(I'm using a simple disk cache in /tmp, with mod_mapcache from the 
Ubuntu libmapcache 1.0.0-3 package; Mapserver 6.2.1 is on the same 
machine, running in 64-bit Ubuntu 12.04. Mapserver works fine, and 
reports no errors [I think]. My client is Google Earth 7.)

Thanks for taking a look,

   - John D. Evans
     GST, Inc / Greenbelt, MD

Below is my mapcache.xml file (actually an excerpt of it:
the real one has more tilesets and sources).

<mapcache>
    <metadata>
       <title>my mapcache service</title>
       <abstract>woot! this is a service abstract!</abstract>
    </metadata>

    <cache name="disk" type="disk">
       <base>/tmp</base>
       <symlink_blank/>
    </cache>

    <format name="PNG_BEST" type ="PNG">
       <compression>best</compression>
    </format>
    <format name="PNG_FAST" type ="PNG">
       <compression>fast</compression>
    </format>

      <source name="CSPP_CloudPhase" type="wms">
       <http>
          <url>http://localhost/cgi-bin/mapserv?</url>
       </http>
       <getmap>
          <params>
             <FORMAT>image/png</FORMAT>
             <LAYERS>iicmocp_daily</LAYERS>
             <MAP>/raid/maps/viirs.map</MAP>
          </params>
       </getmap>
    </source>

    <tileset name="CSPP_Cloud_Phase_EDR">
       <metadata>
          <title>VIIRS Cloud Phase from NASA GSFC DRL</title>
          <abstract>Detailed description goes here</abstract>
       </metadata>
       <source>CSPP_CloudPhase</source>
       <cache>disk</cache>
       <format>PNG</format>
       <grid>WGS84</grid>
       <metatile>2 2</metatile>
       <expires>3600</expires>
       <auto_expire>3600</auto_expire>
       <!-- <metabuffer>10</metabuffer> -->
    </tileset>

    <default_format>PNG_FAST</default_format>

    <service type="wms" enabled="true">
       <full_wms>assemble</full_wms>
       <resample_mode>bilinear</resample_mode>
       <format>PNG_FAST</format>
       <!-- <maxsize>4096</maxsize> -->
    </service>

    <service type="wmts" enabled="true"/>
    <service type="tms" enabled="true"/>
    <service type="kml" enabled="true"/>
    <service type="gmaps" enabled="true"/>
    <service type="ve" enabled="true"/>
    <service type="demo" enabled="true"/>

    <lock_dir>/tmp</lock_dir>
    <errors>report</errors>
    <threaded_fetching>true</threaded_fetching>

</mapcache>