[postgis-devel] [PostGIS] #582: [wktraster] Correct pixel size calculations

[PostGIS]

#582: [wktraster] Correct pixel size calculations
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 Reporter:  dzwarg     |       Owner:  dzwarg         
     Type:  defect     |      Status:  new            
 Priority:  medium     |   Milestone:  WKTRaster 0.1.6
Component:  wktraster  |     Version:  1.5.X          
 Keywords:             |  
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Comment(by dzwarg):

 Well, skewx and skewy may be unequal for small rotations. The ratio of
 skewx / scaly and skewy / scalex remains constant, though.

 I do know what you refer to, though -- when a raster is indeed skewed, or
 diamond shaped, there are really 2 rotations; one for the amount off the X
 axis, and one for the amount off the Y axis.

 Would it be acceptable if ST_Rotation returned NaN for conditions when
 non-uniform rotations are detected, and was documented as such?

 I agree that st_setrotation doesn't have this problem, since you are
 setting the skew/scale for both dimensions at the same time.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/582#comment:3>
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