On Thursday 22 January 2004 16:18, [EMAIL PROTECTED] ( Marc) (A.) (Lehmann ) wrote: >On Thu, Jan 22, 2004 at 12:43:18PM -0700, Steve Strobel <[EMAIL PROTECTED]> wrote: >> I tried using the perspective transform to adjust the corners of >> the image so the section lines would be horizontal and vertical. > >That's actually correctly doing what the perspective transform is > doing (try to imagine a plane with rectangles on it, in an angle > towards you). > >From what you are writing, I'd say he shearing transform is > *exactly* what you need, so what kind of problems are you facing > when using a shear transform?
You may also be trying to undo the spherical component of the mapping. USGS maps, and most maps in general are on a spherical plane usually, sometimes on a modification of the mercator projection. This may be something that the gimp coders could add, a 'de-sphericalizer'. Make the user put in the 1/xxxxxx ratio as shown on the map and use that to calculate what to do. -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) 99.22% setiathome rank, not too shabby for a WV hillbilly Yahoo.com attornies please note, additions to this message by Gene Heskett are: Copyright 2004 by Maurice Eugene Heskett, all rights reserved. _______________________________________________ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user