[Tilecache] TileCache and The GDAL WMS-C Driver

[Christopher Helm]

Hi list,

I'm trying to use the latest build of GDAL (with wms and wms-c support) to access TileCache. The GDAL documentation provides an "example" tilecache call that doesn't seem work.

GDAL Example (xml file):

<GDAL_WMS>
    <Service name="WMS">
        <Version>1</Version>
        <ServerUrl>http://labs.metacarta.com/wms-c/Basic.py?</ServerUrl>
        <Layers>basic</Layers>
    </Service>
    <DataWindow>
        <UpperLeftX>-180.0</UpperLeftX>
        <UpperLeftY>90.0</UpperLeftY>
        <LowerRightX>180.0</LowerRightX>
        <LowerRightY>-90.0</LowerRightY>
        <SizeX>268435456</SizeX>
        <SizeY>134217728</SizeY>
        <TileLevel>19</TileLevel>
    </DataWindow>
    <Projection>EPSG:4326</Projection>
    <OverviewCount>19</OverviewCount>
    <BlockSizeX>256</BlockSizeX>
    <BlockSizeY>256</BlockSizeY>
    <BandsCount>3</BandsCount>
</GDAL_WMS>


If I issue gdalinfo on this file it reads it successfully (just as it does for the WMS example), but trying to access the file via any other route (ie gdal_translate) breaks with:

0ERROR 1: GDALWMS: Unable to download block 0, 0 (http://labs.metacarta.com/wms-c/Basic.py?request=GetMap&version=1.1.1&layers=basic&styles=&srs=EPSG:4326&format=image/jpeg&width=1024&height=1024&bbox=-180.000000,-90.000000,-143.136000,-53.136000). HTTP status code: 404
ERROR 1: IReadBlock failed at X offset 0, Y offset 0
ERROR 1: GetBlockRef failed at X block offset 0, Y block offset 0


This seems like it could be a gdal problem, but I was hoping someone on this list might have a way around this issue?

Chris