Changes between Version 11 and Version 12 of PostGIS_Raster_SoC_Idea_2012/Distance_Analysis_Tools/document

Timestamp:

Jul 12, 2012, 10:51:56 PM (12 years ago)

Author:

qliu

Comment:

—

PostGIS_Raster_SoC_Idea_2012/Distance_Analysis_Tools/document

@@ -32 +32 @@
 ==== 1. The raster source approach ====
 
-  The first approach is similar to what is found in most GIS package. The source points (or geometries) are converted to a raster of sources and this raster is passed to the function. The function iterates over the pixels (or over the source points???) assigning the distance to the nearest point (or assigning minimum values to pixels within a circle progressively growing around each point???).
+  The first approach is similar to what is found in most GIS package. The source points (or geometries) are converted to a raster of sources and this raster is passed to the function. The function iterates over the pixels (__or over the source points???__) assigning the distance to the nearest point (__or assigning minimum values to pixels within a circle progressively growing around each point???__).
 
-Converting one or a set of source geometries to one raster can be performed like this in PostGIS:
+  Converting one or a set of source geometries to one raster can be performed like this in PostGIS:
  
-raster ST_Union(raster ST_AsRaster(source_geom, list of parameters for raster specifications))
+{{{#!sql raster ST_Union(raster ST_AsRaster(source_geom, list of parameters for raster specifications))}}}
 
 The Euclidean distance from each pixel to its nearest source pixel can then be computed using ST_MapAlgebra.