Fix crash when generating profile of 2d line using line as curve

Fixes qgis#55496
nyalldawson · Dec 4, 2023 · 40e9e1a · 40e9e1a
1 parent 728e596
commit 40e9e1a
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Showing 2 changed files with 48 additions and 4 deletions.
diff --git a/src/core/vector/qgsvectorlayerprofilegenerator.cpp b/src/core/vector/qgsvectorlayerprofilegenerator.cpp
@@ -268,7 +268,7 @@ void QgsVectorLayerProfileResults::visitFeaturesAtPoint( const QgsProfilePoint &
                 const double snappedDistance = point.distance() < partBounds.xMinimum() ? partBounds.xMinimum()
                                                : point.distance() > partBounds.xMaximum() ? partBounds.xMaximum() : point.distance();
 
-                const QgsGeometry cutLine( new QgsLineString( QgsPoint( snappedDistance, minZ ), QgsPoint( snappedDistance, maxZ ) ) );
+                const QgsGeometry cutLine( new QgsLineString( QgsPoint( snappedDistance, qgsDoubleNear( minZ, maxZ ) ? minZ - 1 : minZ ), QgsPoint( snappedDistance, maxZ ) ) );
                 QgsGeos cutLineGeos( cutLine.constGet() );
 
                 const QgsGeometry points( cutLineGeos.intersection( line ) );
@@ -948,7 +948,7 @@ bool QgsVectorLayerProfileGenerator::generateProfileForLines()
 
         const double *inX = ls->xData();
         const double *inY = ls->yData();
-        const double *inZ = ls->zData();
+        const double *inZ = ls->is3D() ? ls->zData() : nullptr;
         double *outX = newX.data();
         double *outY = newY.data();
         double *outZ = newZ.data();
@@ -975,11 +975,11 @@ bool QgsVectorLayerProfileGenerator::generateProfileForLines()
           const double distanceAlongOriginalGeometry = curveGeos.lineLocatePoint( QgsPoint( x, y ) );
           std::unique_ptr< QgsPoint > closestOriginalPoint( curve->interpolatePoint( distanceAlongOriginalGeometry ) );
 
-          double z = *inZ++;
+          double z = inZ ? *inZ++ : 0;
 
           *outX++ = x;
           *outY++ = y;
-          *outZ++ = closestOriginalPoint->z();
+          *outZ++ = std::isnan( closestOriginalPoint->z() ) ? 0 : closestOriginalPoint->z();
           if ( extZOut )
             *extZOut++ = z + extrusion;
 

diff --git a/tests/src/python/test_qgsvectorlayerprofilegenerator.py b/tests/src/python/test_qgsvectorlayerprofilegenerator.py
@@ -366,6 +366,50 @@ def testLineGenerationAbsolute(self):
         self.assertAlmostEqual(results.zRange().lower(), 27.7064, 2)
         self.assertAlmostEqual(results.zRange().upper(), 51.7598, 2)
 
+    def testLineGenerationFollowingLinestringExactly(self):
+        vl = QgsVectorLayer('MultiLineString?crs=EPSG:3857', 'lines', 'memory')
+        self.assertTrue(vl.isValid())
+
+        for line in ['MultiLineString ((872381.44973557780031115 6035318.57090197317302227, 868258.19322114891838282 6039288.30190788581967354, 870254.02483185648452491 6048565.62906535062938929, 884224.8461068095639348 6045999.55985158402472734, 876087.99415546329692006 6035472.0964104887098074))']:
+            f = QgsFeature()
+            f.setGeometry(QgsGeometry.fromWkt(line))
+            self.assertTrue(vl.dataProvider().addFeature(f))
+
+        vl.elevationProperties().setClamping(Qgis.AltitudeClamping.Absolute)
+
+        curve = QgsLineString()
+        curve.fromWkt(
+            'LineString(872381.44973557780031115 6035318.57090197317302227, 868258.19322114891838282 6039288.30190788581967354, 870254.02483185648452491 6048565.62906535062938929, 884224.8461068095639348 6045999.55985158402472734, 876087.99415546329692006 6035472.0964104887098074)')
+        req = QgsProfileRequest(curve)
+        req.setCrs(QgsCoordinateReferenceSystem('EPSG:3857'))
+
+        generator = vl.createProfileGenerator(req)
+        self.assertTrue(generator.generateProfile())
+        results = generator.takeResults()
+
+        self.assertEqual(self.round_dict(results.distanceToHeightMap(), 1),
+                         {0.0: 0.0, 5723.6: 0.0, 15213.2: 0.0, 29417.7: 0.0, 42723.2: 0.0})
+
+        self.assertAlmostEqual(results.zRange().lower(), 0.0, 2)
+        self.assertAlmostEqual(results.zRange().upper(), 0.0, 2)
+
+        # try with just a part of the original linestring as the capture curve
+        curve = QgsLineString()
+        curve.fromWkt(
+            'LineString (872381.44973557780031115 6035318.57090197317302227, 868258.19322114891838282 6039288.30190788581967354, 870254.02483185648452491 6048565.62906535062938929)')
+        req = QgsProfileRequest(curve)
+        req.setCrs(QgsCoordinateReferenceSystem('EPSG:3857'))
+
+        generator = vl.createProfileGenerator(req)
+        self.assertTrue(generator.generateProfile())
+        results = generator.takeResults()
+
+        self.assertEqual(self.round_dict(results.distanceToHeightMap(), 1),
+                         {0.0: 0.0, 5723.6: 0.0, 15213.2: 0.0})
+
+        self.assertAlmostEqual(results.zRange().lower(), 0.0, 2)
+        self.assertAlmostEqual(results.zRange().upper(), 0.0, 2)
+
     def testLineGenerationFollowingLinestringZExactly(self):
         vl = QgsVectorLayer('MultiLineStringZ?crs=EPSG:3857', 'lines', 'memory')
         self.assertTrue(vl.isValid())