pixmap symbol quality question

[Sean Gillies]

On May 19, 2006, at 9:13 AM, Didrik Pinte wrote:

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> Hi,
>
> I'm using two pixmap symbols.
>
> The rendering in the legend is perfect but the color of the symbols in
> the map is not exactly the same.=20
>
> Is it possible to correct the problem ?
>
> I'm running mapserver 4.4 and the output is PNG file.
>
> I can provide lots of details if needed (even some example images).
>
> Many thanks for your help.
>
> Didrik

Didrik,

Are you using a 256 color output format? If so, it is possible that  
the palette is filled before the symbols are rendered onto the map.  
In that case, GD tries to do its best to find nearest colors from the  
palette.

You could switch to a RGB output format, or you could try the  
following hack: create a layer at the head of your mapfile which  
renders the symbol once using an inline feature. This will push all  
the symbol's colors into the image palette early. Then render the  
rest of your map on top. Of course, this really just pushes the  
problem (lack of colors) into another layer, but maybe it wouldn't  
appear so bad for another layer.

cheers,
Sean

---
Sean Gillies
http://zcologia.com