From: Sandro Santilli <strk@keybit.net>
Date: Thu, 8 Sep 2005 22:58:47 +0000 (+0000)
Subject: minor speedups in distance()
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=529300782e37a527eac11812f1c86f647eedf95b;p=postgis

minor speedups in distance()


git-svn-id: http://svn.osgeo.org/postgis/branches/pgis_1_0@1895 b70326c6-7e19-0410-871a-916f4a2858ee
---

diff --git a/CHANGES b/CHANGES
index af485f54f..dd18184b0 100644
--- a/CHANGES
+++ b/CHANGES
@@ -9,6 +9,7 @@ PostGIS 1.0.4
 	- Looser syntax acceptance in box3d parser
 	- Documentation improvements
 	- More robust selectivity estimator 
+	- Minor speedup in distance()
 
 PostGIS 1.0.3
 2005/08/08
diff --git a/lwgeom/measures.c b/lwgeom/measures.c
index 7fa33a167..e0f5cc723 100644
--- a/lwgeom/measures.c
+++ b/lwgeom/measures.c
@@ -459,15 +459,21 @@ double distance2d_poly_poly(LWPOLY *poly1, LWPOLY *poly2)
 	//   if intersect, return 0
 	for (i=0; i<poly1->nrings; i++)
 	{
-		double dist = distance2d_ptarray_poly(poly1->rings[i], poly2);
-		if (i) mindist = LW_MIN(mindist, dist);
-		else mindist = dist;
+		int j;
+		for (j=0; j<poly2->nrings; j++)
+		{
+			double d = distance2d_ptarray_ptarray(poly1->rings[i],
+				poly2->rings[j]);
+			if ( d <= 0 ) return 0.0;
+
+			if (i) mindist = LW_MIN(mindist, d);
+			else mindist = d;
+		}
 
 #ifdef PGIS_DEBUG
-		lwnotice("  ring%d dist: %f, mindist: %f", i, dist, mindist);
+		lwnotice("  ring%d dist: %f, mindist: %f", i, d, mindist);
 #endif
 
-		if ( mindist <= 0 ) return 0.0; // intersection
 	}
 
 	// otherwise return closest approach of rings (no intersection)