[mapserver-users] Just starting out...

[Frank Warmerdam]

tuckeratwork wrote:
>     What information do you have now defining the regions for the
>     cutouts?  Are
>     you expecting to need to manually define polygons for these by
>     digitizing? 
> 
>  
> First, wow - I'm getting answers from the source!  I'm sorry to bother 
> you with such trivial questions.

Tucker,

The questions are not at all trivial, though possibly hard to give
solid answers for.

> Yes, I expect to write a quick digitizing program to define the 
> boundaries and cutouts.  There's some other meta data I need to collect 
> too.  The borders aren't in the header like the BSB/KAP files.
>  
> I'll definitely check out the gdal_rasterize utility - that's the exact 
> kind of advice I was looking for.  I'm a developer and don't mind 
> writing custom code if needed with gdal, etc.

The utility is available as part of GDAL and is documented at:

   http://www.gdal.org/gdal_rasterize.html

Note the -i flag to invert the sense of what is inside or outside.

> How about the quilting aspects of it all?  Will I get the type of tile 
> results that GeoGarage got?  I'm not really sure how they did what they 
> did - perhaps they used MapServer too...

MapServer should be able to quilt images fairly well if you can burn away
all the stuff you don't want to show, and then order them as you want them
layered.  If the images are not all in the same coordinate system you may
need to use multiple LAYER's for them otherwise you can just dump them into
a tileindex (ie. shapefile) with some care to ordering.

When burning away uninteresting parts of the images make sure you burn them
out to a particular value that can be used as the OFFSITE value in your
LAYER definition - assuming you don't go the alpha transparency route which
is somewhat involved.

What you want to do should be achievable but may be somewhat challenging.
I'm not sure that it is critical to do it through mapserver.  You could
likely achieve something similar by creating a suitable mosaic image, and
gdalwarp'ing the individual maps into that in a suitable order (after
appropriate masking).

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent