Fix crash, missing points in some corner cases

qgis · Apr 5, 2019 · 4582cb8 · 4582cb8
1 parent 426382c
commit 4582cb8
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Showing 4 changed files with 53 additions and 1 deletion.
diff --git a/src/core/symbology/qgslinesymbollayer.cpp b/src/core/symbology/qgslinesymbollayer.cpp
@@ -1119,7 +1119,13 @@ void QgsTemplatedLineSymbolLayerBase::renderPolylineInterval( const QPolygonF &p
     // (or trace past the final point)
     collectOffsetPoints( points, symbolPoints, painterUnitInterval, lengthLeft );
 
-    if ( symbolPoints.constFirst() == symbolPoints.constLast() )
+    if ( symbolPoints.empty() )
+    {
+      // no symbols to draw, shortcut out early
+      return;
+    }
+
+    if ( symbolPoints.count() > 1 && symbolPoints.constFirst() == symbolPoints.constLast() )
     {
       // avoid duplicate points at start and end of closed rings
       symbolPoints.pop_back();

diff --git a/tests/src/python/test_qgsmarkerlinesymbollayer.py b/tests/src/python/test_qgsmarkerlinesymbollayer.py
@@ -275,6 +275,52 @@ def testRingNoDupe(self):
         rendered_image = self.renderGeometry(s, g)
         assert self.imageCheck('markerline_ring_no_dupes', 'markerline_ring_no_dupes', rendered_image)
 
+    def testSinglePoint(self):
+        s = QgsLineSymbol()
+        s.deleteSymbolLayer(0)
+
+        marker_line = QgsMarkerLineSymbolLayer(True)
+        marker_line.setPlacement(QgsTemplatedLineSymbolLayerBase.Interval)
+        marker_line.setInterval(1000)
+        marker_line.setIntervalUnit(QgsUnitTypes.RenderMapUnits)
+        marker = QgsSimpleMarkerSymbolLayer(QgsSimpleMarkerSymbolLayer.Circle, 4)
+        marker.setColor(QColor(255, 0, 0, 100))
+        marker.setStrokeStyle(Qt.NoPen)
+        marker_symbol = QgsMarkerSymbol()
+        marker_symbol.changeSymbolLayer(0, marker)
+        marker_line.setSubSymbol(marker_symbol)
+        line_symbol = QgsLineSymbol()
+        line_symbol.changeSymbolLayer(0, marker_line)
+
+        s.appendSymbolLayer(marker_line.clone())
+
+        g = QgsGeometry.fromWkt('LineString(0 0, 0 10, 10 10)')
+        rendered_image = self.renderGeometry(s, g)
+        assert self.imageCheck('markerline_single', 'markerline_single', rendered_image)
+
+    def testNoPoint(self):
+        s = QgsLineSymbol()
+        s.deleteSymbolLayer(0)
+
+        marker_line = QgsMarkerLineSymbolLayer(True)
+        marker_line.setPlacement(QgsTemplatedLineSymbolLayerBase.Interval)
+        marker_line.setOffsetAlongLine(1000)
+        marker_line.setIntervalUnit(QgsUnitTypes.RenderMapUnits)
+        marker = QgsSimpleMarkerSymbolLayer(QgsSimpleMarkerSymbolLayer.Circle, 4)
+        marker.setColor(QColor(255, 0, 0, 100))
+        marker.setStrokeStyle(Qt.NoPen)
+        marker_symbol = QgsMarkerSymbol()
+        marker_symbol.changeSymbolLayer(0, marker)
+        marker_line.setSubSymbol(marker_symbol)
+        line_symbol = QgsLineSymbol()
+        line_symbol.changeSymbolLayer(0, marker_line)
+
+        s.appendSymbolLayer(marker_line.clone())
+
+        g = QgsGeometry.fromWkt('LineString(0 0, 0 10, 10 10)')
+        rendered_image = self.renderGeometry(s, g)
+        assert self.imageCheck('markerline_none', 'markerline_none', rendered_image)
+
     def renderGeometry(self, symbol, geom, buffer=20):
         f = QgsFeature()
         f.setGeometry(geom)

diff --git a/..._images/symbol_markerline/expected_markerline_none/expected_markerline_none.png b/..._images/symbol_markerline/expected_markerline_none/expected_markerline_none.png
diff --git a/...ges/symbol_markerline/expected_markerline_single/expected_markerline_single.png b/...ges/symbol_markerline/expected_markerline_single/expected_markerline_single.png