[Proj] Having all projection inverses was Re: Why

[William Kyngesburye]

On Oct 29, 2008, at 2:39 PM, Melita Kennedy wrote:

>> But Aitoff or Winkel Tripel.  What source information is in either  
>> projection.
>> Are people now going to digitize NGS maps?  Certainly nobody uses  
>> Winkel
>> Tripel for cadastral application---do they?
>>
>> Just very curious.
>
> At least how we used to do it, you also must have an inverse to  
> project imagery
> (once the output cells are defined, unproject to figure out the cell  
> values).
>
Ah, there's a point - GRASS uses inverse-projecting to project rasters  
(for speed, I think).  I once had to revert to Arc to project the  
GLOBE data to Winkel Tripel to generate shaded relief for a client.   
Bleh.  (the gdalwarp tool didn't work at the time on this huge  
dataset, I haven't tried since)


-----
William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
http://www.kyngchaos.com/

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