Lining up tiles and styling

[Graham Davis]

Stephen is correct, and the kamap code uses a buffer around each tile to 
get around this issue.  I've worked with some modified Kamap code, and 
it uses the GD library to cut up the tiles, with a buffer not only 
around each tile but also around the main metatile that is fetched from 
Mapserver.  Our setup uses a 10 pixel buffer around each tile, and twice 
that for the buffer around the metatile.

-- 
Graham Davis
Refractions Research Inc.
gdavis at refractions.net



Stephen Woodbridge wrote:

> Ed,
>
> Have you looked at http://ka-map.maptools.org/
>
> This is a google like AJAX client that uses php and mapserver on the 
> backend to generate tiles. Even if you do not want to use the whole 
> thing, you might look at tile.php to see how they resolve these issues.
>
> -Steve W.
>
> Ed Dowding wrote:
>
>> I'm tiling mapserver tile requests to form a map. On those tiles are 
>> lines
>> styled with a thickness. The lines also have rounded ends.
>>
>> Which means that when a line goes off the edge of a tile, they're
>> "rounding-off" making it impossible to tile from separate requests.
>>
>> Quite difficult to explain, so here's a picture..
>> http://citysafe.org/temp/mapRounding.png
>>
>> One approach would be to get mapserver to draw the line beyond the 
>> extent of
>> its tile... but this is, I think, hypothetical, since I cant see that 
>> it's
>> possible from the docs.
>>
>>
>> Does anyone have any experience of this?
>>
>> Thanks in advance,
>>
>> Ed
>>