[postgis-devel] [PostGIS] #1331: [raster] Physically relevant geotransform settings

[PostGIS]

#1331: [raster] Physically relevant geotransform settings
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 Reporter:  bnordgren       |       Owner:  pracine              
     Type:  enhancement     |      Status:  new                  
 Priority:  medium          |   Milestone:  PostGIS Raster Future
Component:  postgis raster  |     Version:  1.5.X                
 Keywords:                  |  
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Comment(by bnordgren):

 The method to calculate these physically relevant parameters given an
 arbitrary transform is presented on DevWikiRealParameters.

 This would likely result in a single function with a signature like:

 {{{
 ST_GetGeoTransform(raster rast)
 }}}

 returning a setof 4 values:

  * i_magnitude
  * j_magnitude
  * theta_i
  * theta_ij

 After implementation, ST_GetRotation should be modified to return
 `theta_i` from this function. Currently, ST_GetRotation returns NaN if
 `theta_ij` is not +-90 degrees.

 If other accessors for individual parameters are desired, they may be
 implemented on top of the two general functions presented here with little
 or no loss of performance.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/1331#comment:1>
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