[Mapserver-users] .tiff resolution

[Charlton Purvis]

Thanks, Ed.  Yes, that's what I considered from the get-go.  But maybe it's my naiveté showing when I say that I decided to go the TIFF route since I thought that it would be more CPU intensive for MapServer to crunch the shapefile and produce nice layers than it would be for it to render the TIFF.  I can certainly accept that fact that I could be mistaken, but considering what my goals are, maybe I'm not too far off base.

Goal (at least a current one):  I would like to produce maps w/ elevation as a "layer" and then put other layers on top of it (roads, flooding paths, etc.).  Current thinking is that I don't want the server to spend time trying to render the elevation map when it should be busier working w/ the other layers.

Flip-side:  Maybe it all boils down to keeping everything consistent.  It's fair to say that if I want high resolution for the streets, then I'd better have the same resolution w/ the elevations.  And an easy way to do that would be to work w/ only shapefiles.  In theory.

But is it unreasonable (or simply dumb) to think that I can have a pretty background that is reasonably non CPU intensive to render while superimposing layers that would require higher CPU priority?  Perhaps it's time for GIS 101.  I've been a computer scientist for a long time, and I'm slowly migrating to the GIS frame-of-mind.  Slowly but surely.

Thanks, all.

Charlton

-----Original Message-----
From: Ed McNierney [mailto:ed at topozone.com] 
Sent: Friday, February 07, 2003 2:51 PM
To: Charlton Purvis; Hankley, Chip; MapServer List (E-mail)
Subject: RE: [Mapserver-users] .tiff resolution

Charlton -

If you have the data in a shapefile, you will get MUCH better output results by serving that data as a shapefile in MapServer than by converting it to a TIF and then serving the TIF.  Both processes essentially do the same thing (generate a raster image) but MapServer can customize that image each time to the requested output resolution, whereas the TIF image is frozen at a particular resolution.

	- Ed

Ed McNierney
President and Chief Mapmaker
TopoZone.com / Maps a la carte, Inc.
73 Princeton Street, Suite 305
North Chelmsford, MA  01863
ed at topozone.com
(978) 251-4242