Changes between Version 154 and Version 155 of WKTRaster/SpecificationWorking03

Timestamp:

09/20/11 08:11:29 (13 years ago)

Author:

dustymugs

Comment:

—

WKTRaster/SpecificationWorking03

@@ -68 +68 @@
 2. ST_Intersects(raster rastA, integer bandA, raster rastB, integer bandB) -> boolean
 
-The ST_Intersects(raster, geometry) functions may need to be adapted to use ST_Intersects(raster, raster).  The difficulty will be for the functions to decide whether or not converting the raster to a geometry or converting the geometry to a raster is faster.
+A refactored set of St_Intersects() for testing a raster and a geometry.  The first set converts the geometry to a raster to see if the two rasters intersect.
+
+3. ST_Intersects(rast raster, geom geometry, nband integer DEFAULT NULL) -> boolean
+
+4. ST_Intersects(rast raster, nband integer, geom geometry) -> boolean
+
+The second set of ST_Intersects() for testing a raster and a geometry converts the raster to a geometry and sees if the geometries intersect.
+
+5. ST_Intersects(geom geometry, rast raster, nband DEFAULT NULL) -> boolean
+
+The order in which the geometry and raster are passed into ST_Intersects determines which method of testing is used.  If geometry is first, the raster is converted to a set of geometries.  If raster is first, the geometry is converted to a raster.
+
+These set of functions are required because there are cases where ST_Intersects(raster, geometry) != ST_Intersects(geometry, raster).
+
+
 
 '''ST_AsRaster(geometry, pixeltype, val, nodataval, ulx, uly, width, height, pixelsizex, pixelsizey, skewx, skewy) -> raster - done see below'''