[Tilecache] Re: MetaTiling - does projection affect?

[Mark Deneen]

On 5/6/2010 10:23 AM, christopher.schmidt at nokia.com wrote:
>> Chris,
>>
>> Would you be interested in a patch to the DiskCache which makes it so
>> that TileCache will not cache any more tiles, other than what is in the
>> existing cache?  If a tile is missing, the DiskCache will return a
>> configurable default tile image.
>>     
> Is this related to the above thread? I don't understand; lack of locking 
> and adding a feature to TileCache seem unrelated to me.
>
>   
I had serious issues running TileCache "live" with meta tiling, so I
opted to seed everything which I want to be viewed.  I then needed a way
to provide a default tile.
>> We use this so that we can seed the whole world, and many levels of
>> North America.  Then, if a user tries to zoom in to an area which we
>> don't have tiles for, they just get a default tile image.
>>
>> Unfortunately, now that I see your message, I wrote this patch because
>> of the behavior I saw without the patch to 2.10.
>>     
> I don't understand why this would be the case; I mean, the feature you 
> wrote isn't solved by a patch that exists in TileCache, so if you want
> that feature, you'll need to write a patch.
>
> However, it shouldn't go in the Cache. It should be a Layer option;
> missingTile=/path/to/file.png or some such, and then at the layer level,
> we can read that when an empty tile is found and return that instead.
>
> A brief look suggests that Layer.render might be the right place to add
> such a check.
>
>   
I'll look into the Layer.  Thanks.

> -- Chris
>
>