Mailing Lists: Apple Mailing Lists
Image of Mac OS face in stamp
 
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: converting a paper contour map to a digital 3D image

Tony,

It might be helpful to look at your problem in 3 pieces: gathering the contours, generating the 2.5-d surface, and visualizing it. My experience is that different packages excel at different parts of this process.

There's lots of software to do the contour tracing, mostly in the Windoze world though. I've never had to do this part of it on a Mac. Another approach is to trace the contours on a digitizing tablet of some sort, maybe even one of the Summagraphics tablets.

You might also consider sending this work out to a service bureau. Digitizing maps defines tedium for me. But before you produce the data, look around for available DEMs for your study area: maybe from the managing agency, or lower resolution from http://edcdaac.usgs.gov/gtopo30/gtopo30.html or http://www.ngdc.noaa.gov/seg/topo/globe.shtml

GRASS is a pretty good tool for generating surfaces from contours, especially if you're not sure at the beginning how you want to generate them. There are always parts of the problem that you didn't think about at the beginning: exact interpolation of all contours? What happens at the edges? What about lakes? How smooth should the surface be?

The visualization available in GRASS is pretty decent. Google for NVIZ. You can do simpler things as well.
--
----
Hal Mueller email@hidden
Mobile Geographics LLC http://www.mobilegeographics.com/
Seattle, Washington (206) 297-9575
Get MapTap for PalmOS: http://www.mobilegeographics.com/maptap/
_______________________________________________
scitech mailing list | email@hidden
Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/scitech
Do not post admin requests to the list. They will be ignored.
References: 
 >converting a paper contour map to a digital 3D image (From: email@hidden)



Visit the Apple Store online or at retail locations.
1-800-MY-APPLE

Contact Apple | Terms of Use | Privacy Policy

Copyright © 2007 Apple Inc. All rights reserved.