quadkey((0,0,0)) about mapproxy HOT 2 CLOSED

Reading this: http://msdn.microsoft.com/en-us/library/bb259689.aspx

there appears to be no level 0 for quadkeys/microsoft. The first zoom level consists of 4 (256x256px) tiles or one 512x512px tile. The same conclusion can be drawn from just using the tiles, 0.jpg is the north west tile:
http://ecn.t2.tiles.virtualearth.net/tiles/r0.jpeg?g=1252&mkt=en-US&shading=hill
something shorter also returns a bad request
http://ecn.t2.tiles.virtualearth.net/tiles/0?g=1252&mkt=en-US&shading=hill

there is a 0 tile for osm slippy map: http://a.tile.openstreetmap.org/0/0/0.png

and for google: http://mt0.googleapis.com/vt/lyrs=t@131,r@214000000&hl=nl&src=api&x=0&y=0&z=0&s=

so I think it is not a bug for mapproxy, just that 0,0,0 is not defined for quadkey and should not be requested?

Actually even 0,0,1 should not return quadkey 0 because the only valid tile 0 is from z1,x0,y0

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Thanks for the explanation.
I didn't noticed there are 4 tiles for the first zoom level in Bing.
It's not a bug for mapproxy but for the Autocad client who request (0,0,0) at map init and he should not.
I just want to verify that with you.

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