[geos-commits] r3554 - branches/3.3/src/operation/overlay/snap

[svn_geos at osgeo.org]

Author: strk
Date: 2011-12-16 06:12:20 -0800 (Fri, 16 Dec 2011)
New Revision: 3554

Modified:
   branches/3.3/src/operation/overlay/snap/LineStringSnapper.cpp
Log:
Make debugging output of LineStringSnapper more readable

Modified: branches/3.3/src/operation/overlay/snap/LineStringSnapper.cpp
===================================================================
--- branches/3.3/src/operation/overlay/snap/LineStringSnapper.cpp	2011-12-15 14:36:15 UTC (rev 3553)
+++ branches/3.3/src/operation/overlay/snap/LineStringSnapper.cpp	2011-12-16 14:12:20 UTC (rev 3554)
@@ -65,6 +65,10 @@
 {
   if ( srcCoords.empty() ) return;
 
+#if GEOS_DEBUG
+cerr << "Snapping vertices of: " << srcCoords << endl;
+#endif
+
 	using geom::CoordinateList;
 
 	geom::Coordinate::ConstVect::const_iterator not_found = snapPts.end();
@@ -87,7 +91,7 @@
 		if ( found == not_found )
 		{	// no snaps found (or no need to snap)
 #if GEOS_DEBUG
-cerr << "No snap found" << endl;
+cerr << " no snap found" << endl;
 #endif
 			continue;
 		}
@@ -96,14 +100,14 @@
 		const Coordinate& snapPt = *(*found);
 		
 #if GEOS_DEBUG
-cerr << "Found snap point " << snapPt << endl;
+cerr << " found snap point " << snapPt << endl;
 #endif
 
 		// update src with snap pt
 		*it = snapPt;
 
 #if GEOS_DEBUG
-cerr << "Source point became " << srcPt << endl;
+cerr << " source point became " << srcPt << endl;
 #endif
 
 		// keep final closing point in synch (rings only)
@@ -130,10 +134,6 @@
 		assert(*it);
 		const Coordinate& snapPt = *(*it);
 
-#if GEOS_DEBUG
-cerr << " misuring distance between snap point " << snapPt << " and source point " << pt << endl;
-#endif
-
 		// shouldn't we look for *all* segments to be snapped rather then a single one?
 		if ( snapPt.equals2D(pt) )
 		{
@@ -145,17 +145,21 @@
 		}
 
 		double dist = snapPt.distance(pt);
+#if GEOS_DEBUG
+cerr << " distance from snap point " << snapPt << ": " << dist << endl;
+#endif
+
 		if ( dist < snapTolerance )
 		{
 #if GEOS_DEBUG
-cerr << " points are within distance (" << dist << ") returning iterator to snap point" << endl;
+cerr << " snap point within tolerance, returning iterator to it" << endl;
 #endif
 			return it;
 		}
 	}
 
 #if GEOS_DEBUG
-cerr << " No snap point within distance, returning not-found" << endl;
+cerr << " no snap point within distance, returning not-found" << endl;
 #endif
 
 	return end;
@@ -168,13 +172,13 @@
 			const geom::Coordinate::ConstVect& snapPts)
 {
 
+  // nothing to do if there are no source coords..
+  if ( srcCoords.empty() ) return;
+
 #if GEOS_DEBUG
-cerr << " Snapping segment from: " << srcCoords << endl;
+cerr << "Snapping segments of: " << srcCoords << endl;
 #endif
 
-  // nothing to do if there are no source coords..
-  if ( srcCoords.empty() ) return;
-
 	for ( Coordinate::ConstVect::const_iterator
 			it=snapPts.begin(), end=snapPts.end();
 			it != end;
@@ -235,7 +239,7 @@
 		seg.p1 = *to;
 
 #if GEOS_DEBUG
-cerr << " Checking segment " << seg << " for snapping against point " << snapPt << endl;
+cerr << " Checking segment " << seg << endl;
 #endif
 
 		/**                                                                              * Check if the snap pt is equal to one of
@@ -248,28 +252,45 @@
 		if ( seg.p0.equals2D(snapPt) || seg.p1.equals2D(snapPt) )
 		{
 
+			if (allowSnappingToSourceVertices) {
 #if GEOS_DEBUG
-cerr << " One of segment endpoints equal snap point, returning too_far" << endl;
+cerr << "   snap point matches a segment endpoint, checking next segment"
+     << endl;
 #endif
-			if (allowSnappingToSourceVertices) {
 				continue;
 			} else {
+#if GEOS_DEBUG
+cerr << "   snap point matches a segment endpoint, giving up seek" << endl;
+#endif
 				return too_far;
 			}
 		}
 
 		double dist = seg.distance(snapPt);
+		if ( dist < snapTolerance ) {
+      if ( dist < minDist ) {
 #if GEOS_DEBUG
-cerr << " dist=" << dist << " minDist=" << minDist << " snapTolerance=" << snapTolerance << endl;
+cerr << "   snap point distance " << dist << " within tolerance "
+     << snapTolerance << " and closer than previous candidate " << minDist
+     << endl;
 #endif
-		if ( dist < minDist && dist < snapTolerance )
-		{
+        match = from;
+        minDist = dist;
+      }
 #if GEOS_DEBUG
-cerr << " Segment/snapPt distance within tolerance and closer then previous match (" << dist << ") " << endl;
+      else {
+cerr << "   snap point distance " << dist << " within tolerance "
+     << snapTolerance << " but not closer than previous candidate " << minDist
+     << endl;
+      }
 #endif
-			match = from;
-			minDist = dist;
-		}
+    }
+#if GEOS_DEBUG
+    else {
+cerr << "   snap point distance " << dist << " bigger than tolerance "
+     << snapTolerance << endl;
+    }
+#endif
 	}
 
 	return match;