[Tilecache] World Wind + TileCache

[Martijn van Exel]

Hi all,

I'm attempting to configure World Wind to use a custom data set and
would like to use TileCache for that, because I already use it in
conjuntion with OpenLayers and Virtual Earth clients and already have
some cache stacks built up.

TileCache supports World Wind type tile requests, which are of the
form [LEVEL]/[ROW]/[ROW]_[COLUMN].[FILETYPE_EXT] as described in more
detail here: http://issues.worldwind.arc.nasa.gov/confluence/download/attachments/394/world+wind+tile+systemt.gif

But World Wind allows you to define the base zoomlevel as
LevelZeroTileSizeDegrees parameter, which defines the width of a level
zero tile in degrees. By default this is 36 degrees, so the Earth is
50 tiles on Z0, 200 tiles on Z1, etc - but if you set
LevelZeroTileSizeDegrees to a lower number, I guess TileCache will be
confused.

Even when I set the L0 tiles to be 36 degrees wide, the resulting WMS
requests are not valid. I'm supposed to get something in the range of

bbox=577252.433917 6819405.91068 587036.373536 6829189.8503

(just the BBOX part)

Instead I'm getting

bbox=186892814.594 137924196.802 186895260.579 137926642.787

So I'm doing something wrong here. Does somebody have an idea how to
handle WW zoom levels with TileCache?

Thanks,
Martijn

-- 
martijn van exel -+- mvexel at gmail.com -+- http://schaaltreinen.nl/