[OSM-dev] Can't convert & commit oceantiles_12.png, please help...

Frederik Ramm frederik at remote.org
Wed May 9 16:14:53 BST 2007

Hi Hakan,

> I just modified oceantiles_12.png, but the dat file png2tileinfo.pl
> produces remains exactly the same (I tried 'cmp').

Both the old png file and the one you checked in are identical.

(The PNG files are not identical but the bitmap they describe is. I  
checked by converting both files to PPM format and they ended up the  

As for your question whether one could modify the software to  
directly use the PNG - do play with it, but I estimate that reading  
the PNG in its entirety will consume about 60 MB of RAM, as opposed  
to only a few hundred bytes for the current approach. To be halfway  
efficient you would want to keep the file in RAM and not re-read it  
for every tile rendered, but that would then mean 60 MB missing (or  
at least, having to be swapped out) for other stuff like inkscape...


Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00.09' E008°23.33'

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