[Mapserver-users] why does my raster layer turn my shapefile layer gray?

[Chris Black]

Thanks for the tips.  Right now I'm in a proof-of-concept phase, so 
optimization will wait until the final interface is decided -- if the 
client doesn't like my shaded relief map and wants something else, like 
political entities, there's no need to worry about how to handle the 
relief map.  I'll look at your thoughts again when I've got my map 
layers finalized.

-- Chris

Dylan Keon wrote:

> Chris,
>
> Another option is to export your grayscale shaded relief grid to a 
> georeferenced tiff image, then reduce the color depth of that image 
> using something like Irfanview or Imagemagick.  Try Irfanview since 
> you're on Windows.  Reduce to 64 or 32 colors and see how it 
> looks...you probably won't notice any difference.  This will allow you 
> to use 8-bit output, and will also result in smaller file size.  After 
> that you could also use gdaladdo (part of GDAL) to add overviews to 
> the tiff image to improve rendering times.
>
> If you do stick with 24-bit output you could set up your PHP script so 
> that 24-bit output is used only when the "bayraster" layer is on (or 
> in scale range), and 8-bit output when the layer is off (or out of 
> scale range).  Of course, this won't make any difference if you leave 
> that layer on all the time.
>
> --Dylan
>
>