Changes between Version 16 and Version 17 of UsersWikiplpgsqlfunctions

Timestamp:

09/22/09 13:25:39 (15 years ago)

Author:

bcrosby

Comment:

--

UsersWikiplpgsqlfunctions

@@ -17 +17 @@
     thedirection float;
     midpointrads float;
-    originalsrid int;
     arcenterutm geometry;
     startpointutm geometry;
@@ -27 +26 @@
 
         midpointrads := abs(st_azimuth(arcenterutm,startpointutm) - st_azimuth(arcenterutm,endpointutm));
-        IF midpointrads > pi() THEN midpointrads:= (midpointrads - pi())/2; ELSE midpointrads:= midpointrads/2; END IF;
-
+        IF midpointrads > pi() THEN midpointrads:= (midpointrads - pi())/2; ELSE midpointrads:= midpointrads/2; END IF;
+        IF midpointrads > st_azimuth(arcenterutm,startpointutm) THEN midpointrads:= st_azimuth(arcenterutm,startpointutm)/2; 
         IF direction = 'cw' THEN thedirection := -1*midpointrads; ELSE thedirection := midpointrads; END IF;
         pointonarc := ST_Translate( ST_Rotate( ST_Translate( startpointutm, -1*ST_X(arcenterutm), -1*ST_Y(arcenterutm)), thedirection), ST_X(arcenterutm), ST_Y(arcenterutm));
@@ -37 +36 @@
   LANGUAGE 'plpgsql' IMMUTABLE;
   COMMENT ON FUNCTION st_createarc(geometry,geometry,geometry,text) IS 'Generates an arc based on starting point, ending point, centre of arc, and direction (clockwise: \'cw\', conter-clockwise: \'cc\'). All geometries must be of type POINT and this function returns a linestring of the arc based on the original SRID and 32 points per quarter circle. Requires the utmzone function.'; 
+
+