<div>I'm actually investigating this right now. There's a particular project that myself and a couple friends have involvement in which already has a uniquely created world, which we're looking to take to that next level.</div>
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<div>For practicality's sake, if you wish to use or edit a unique world - means that although you perceive the world as a different size, a 'work-around' would be to work with the data with the same structure as Earth. This will at least produce the results you're after in the work-flow with existing GIS software. If, on the other hand, and like I'm experiencing as well - if you have a preconfigured coordinate system in this virtual world, then it will require additional conversion after the editing process. The goal would be though to be able to import it into a program that understands and allows for capabilities - and adjustments or conversions may have to be made as a final step.
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<div>There are a variety of Open Source and free tools available for these tasks, namely Frank Warmerdam's FWTools with Open EV. It's an incredibly powerful tool-set once you dig in and get yourself familiarized. Frank may have better answers toward the specifics of operating with FWTools and how the work-flow chain can be organized for your needs. (Actually, I've yet to bend Frank's ear about this one.)
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<div>One of the primary goals with this pet project was to implement 'season change' based on a variety of my techniques to produce such imagery in Photoshop, and to incorporate actual realism using satellite or aerial imagery as the source for the landscapes.
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<div>So I suppose my suggestion would be: Convert your datum to Earth's so that it will view properly in existing programs and lend itself to being able to be updated/edited.</div>
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<div>I'm also curious... Would you mind discussing/devulging what your project is for? If not, I'd understand.</div>
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<div>Take care,</div>
<div>Daniel Denk</div>
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<div><span class="gmail_quote">On 11/24/05, <b class="gmail_sendername">Mike Parkes</b> <<a href="mailto:mikeparkes@rogers.com">mikeparkes@rogers.com</a>> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">
<div>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA">This will probably seem like a very weird request…</span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA"> </span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA">What I am interested in doing is using GIS software to map an imaginary planet.</span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA"> </span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA">My starting point is a number of raster images in different projections that cover parts of the planet (e.g. Robinson projection for a world map, different projection for larger-scale maps). I want to be able to integrate and overlay these images, then create vector shapefiles. I'm only concerned with surface mapping (no elevation modeling), at least for now.
</span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA"><span> </span></span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA">The imaginary world is perfectly spherical, but a different size from Earth. Hence, to georeference my images, I need a GIS program that allows user-defined datums. </span>
</p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA"> </span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA">I have been investigating the GeoTiff file format, and (through the Listgeo and geotifcp utilities), it has all the machinery that I need to create an imaginary datum, a map projection and to attach the datum and projection to an image. However, I haven't been able to find a software package that can actually interpret and make use of this specialized GeoTiff information.
</span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA"></span> </p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA">Which free or low-cost GIS software packages can utilize Geotiff's capability for user-defined datums?</span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA"></span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA"> </span></p>
<p style="MARGIN: 0in 0in 0pt"><span lang="EN-CA">Thanks for any help!</span></p></div><br>_______________________________________________<br>Geotiff mailing list<br><a onclick="return top.js.OpenExtLink(window,event,this)" href="mailto:Geotiff@lists.maptools.org">
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