Changes between Version 103 and Version 104 of WKTRaster/SpecificationWorking01

Timestamp:

Jan 5, 2010, 2:57:06 PM (14 years ago)

Author:

pracine

Comment:

—

WKTRaster/SpecificationWorking01

@@ -346 +346 @@
  It might be faster to skip test 2) if this test is not signicantly faster than test 3).
 
-'''ST_Intersection(raster, integer, geometry) -> geometry''' - Returns a geometry that represents the shared portion of the geometry and the raster areas sharing a common meaningfull values. 
+'''ST_Intersection(raster, integer, geometry) -> geometry''' - Returns a set of "geomval" value representing the shared portion of the geometry and the raster areas sharing a common meaningfull values. 
 
  Variant 1: 
@@ -374 +374 @@
   ST_Intersection(raster, raster, 'geometry') -> geometry -- default to band # 1
 
- Returns a geometry that represents the point set intersection of the geometry and the raster. The raster is first polygonised using ST_AsPolygon(raster) and ST_Intersection(geometry, geometry) is then performed between the provided geometry and all the geometries resulting from the polygonisation of the raster.
+ This is a set-returning function (SRF). It returns a set of "geomval" representing the point set intersection of the geometry and the areas of the raster sharing a common meaningfull value (NODATA values ARE taken into account). The raster is first polygonised using ST_AsPolygon(raster) and ST_Intersection(geometry, geometry) is then performed between the provided geometry and all the geometries resulting from the polygonisation of the raster.
 
  If the geometries do not share any space (are disjoint), then an empty geometry collection is returned.