[pal] When merging connected lines, we don't want to use GEOS

"touches" test as this is true for "T" type connected lines Instead we only want to consider lines which begin or end directly at other lines beginning/end. So replace the call to geos touches test with a (much faster) simple test of the start/end vertices being equal
qgis · Apr 20, 2021 · 37a8cb0 · 37a8cb0
1 parent 0eee27f
commit 37a8cb0
Showing 1 changed file with 23 additions and 12 deletions.
diff --git a/src/core/pal/feature.cpp b/src/core/pal/feature.cpp
@@ -2075,19 +2075,30 @@ void FeaturePart::addSizePenalty( std::vector< std::unique_ptr< LabelPosition >
 
 bool FeaturePart::isConnected( FeaturePart *p2 )
 {
-  if ( !p2->mGeos )
-    p2->createGeosGeom();
-
-  try
-  {
-    return ( GEOSPreparedTouches_r( QgsGeos::getGEOSHandler(), preparedGeom(), p2->mGeos ) == 1 );
-  }
-  catch ( GEOSException &e )
-  {
-    qWarning( "GEOS exception: %s", e.what() );
-    QgsMessageLog::logMessage( QObject::tr( "Exception: %1" ).arg( e.what() ), QObject::tr( "GEOS" ) );
+  if ( !nbPoints || !p2->nbPoints )
     return false;
-  }
+
+  // here we only care if the lines start or end at the other line -- we don't want to test
+  // touches as that is true for "T" type joins!
+  const double x1first = x.front();
+  const double x1last = x.back();
+  const double x2first = p2->x.front();
+  const double x2last = p2->x.back();
+  const double y1first = x.front();
+  const double y1last = x.back();
+  const double y2first = p2->x.front();
+  const double y2last = p2->x.back();
+
+  if ( qgsDoubleNear( x1first, x2first ) && qgsDoubleNear( y1first, y2first ) )
+    return true;
+  else if ( qgsDoubleNear( x1first, x2last ) && qgsDoubleNear( y1first, y2last ) )
+    return true;
+  else if ( qgsDoubleNear( x1last, x2first ) && qgsDoubleNear( y1last, y2first ) )
+    return true;
+  else if ( qgsDoubleNear( x1last, x2last ) && qgsDoubleNear( y1last, y2last ) )
+    return true;
+
+  return false;
 }
 
 bool FeaturePart::mergeWithFeaturePart( FeaturePart *other )