[postgis-devel] [PostGIS] #2030: [raster] n-raster ST_MapAlgebra

[PostGIS]

#2030: [raster] n-raster ST_MapAlgebra
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 Reporter:  dustymugs    |       Owner:  dustymugs    
     Type:  enhancement  |      Status:  assigned     
 Priority:  medium       |   Milestone:  PostGIS 2.1.0
Component:  raster       |     Version:  trunk        
 Keywords:               |  
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Comment(by dustymugs):

 distancex and distancey are for passing neighborhoods to the callback, not
 just the pixel value of interest.

 customextent is so that the user can specify an extent that they want.  It
 is in essence a filter and as a side-affect permits correct coverage
 handling.

 I'm not a fan of the expression function variants as they have way too
 many issues with parameter substitution and the most obvious place for
 user error.  So, my statement "This is to replace ALL ST_MapAlgebra
 functions" should be amended to "This is to replace ALL ST_MapAlgebra
 functions using callback functions".  If anything, I'm for leaving the
 existing expression functions as is with no new additions to them to
 provide multi-raster/multi-band support.

-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/2030#comment:6>
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