Avoid calling geos methods for some more trivial point to point geome…

…try calculations
qgis · Sep 22, 2020 · fe50150 · fe50150
1 parent 6a00257
commit fe50150
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diff --git a/src/core/geometry/qgsgeometry.cpp b/src/core/geometry/qgsgeometry.cpp
@@ -609,6 +609,12 @@ double QgsGeometry::sqrDistToVertexAt( QgsPointXY &point, int atVertex ) const
 
 QgsGeometry QgsGeometry::nearestPoint( const QgsGeometry &other ) const
 {
+  // avoid calling geos for trivial point calculations
+  if ( d->geometry && QgsWkbTypes::flatType( d->geometry->wkbType() ) == QgsWkbTypes::Point )
+  {
+    return QgsGeometry( qgsgeometry_cast< const QgsPoint * >( d->geometry.get() )->clone() );
+  }
+
   QgsGeos geos( d->geometry.get() );
   mLastError.clear();
   QgsGeometry result = geos.closestPoint( other );
@@ -618,6 +624,12 @@ QgsGeometry QgsGeometry::nearestPoint( const QgsGeometry &other ) const
 
 QgsGeometry QgsGeometry::shortestLine( const QgsGeometry &other ) const
 {
+  // avoid calling geos for trivial point-to-point line calculations
+  if ( d->geometry && QgsWkbTypes::flatType( d->geometry->wkbType() ) == QgsWkbTypes::Point && QgsWkbTypes::flatType( other.wkbType() ) == QgsWkbTypes::Point )
+  {
+    return QgsGeometry( qgis::make_unique< QgsLineString >( *qgsgeometry_cast< const QgsPoint * >( d->geometry.get() ), *qgsgeometry_cast< const QgsPoint * >( other.constGet() ) ) );
+  }
+
   QgsGeos geos( d->geometry.get() );
   mLastError.clear();
   QgsGeometry result = geos.shortestLine( other, &mLastError );

diff --git a/tests/src/python/test_qgsgeometry.py b/tests/src/python/test_qgsgeometry.py
@@ -1991,6 +1991,13 @@ def testNearestPoint(self):
         wkt = g1.nearestPoint(g2).asWkt()
         self.assertTrue(compareWkt(expWkt, wkt), "Expected:\n%s\nGot:\n%s\n" % (expWkt, wkt))
 
+        # trivial point case
+        expWkt = 'Point (3 4)'
+        wkt = QgsGeometry.fromWkt('Point(3 4)').nearestPoint(QgsGeometry.fromWkt('Point(-1 -8)')).asWkt()
+        self.assertTrue(compareWkt(expWkt, wkt), "Expected:\n%s\nGot:\n%s\n" % (expWkt, wkt))
+        wkt = QgsGeometry.fromWkt('Point(3 4)').nearestPoint(QgsGeometry.fromWkt('LineString( 1 1, 5 1, 5 5 )')).asWkt()
+        self.assertTrue(compareWkt(expWkt, wkt), "Expected:\n%s\nGot:\n%s\n" % (expWkt, wkt))
+
     def testShortestLine(self):
         # test with empty geometries
         g1 = QgsGeometry()
@@ -2022,6 +2029,11 @@ def testShortestLine(self):
         wkt = g1.shortestLine(g2).asWkt()
         self.assertTrue(compareWkt(expWkt, wkt), "Expected:\n%s\nGot:\n%s\n" % (expWkt, wkt))
 
+        # trivial point to point case
+        expWkt = 'LineString (3 4, -1 -8)'
+        wkt = QgsGeometry.fromWkt('Point(3 4)').shortestLine(QgsGeometry.fromWkt('Point(-1 -8)')).asWkt()
+        self.assertTrue(compareWkt(expWkt, wkt), "Expected:\n%s\nGot:\n%s\n" % (expWkt, wkt))
+
     def testBoundingBox(self):
         # 2-+-+-+-+-3
         # |         |