also flip pennants

qgis · May 15, 2024 · d1937f0 · d1937f0
1 parent 0bef68f
commit d1937f0
Showing 1 changed file with 6 additions and 5 deletions.
diff --git a/src/core/mesh/qgsmeshvectorrenderer.cpp b/src/core/mesh/qgsmeshvectorrenderer.cpp
@@ -586,8 +586,9 @@ void QgsMeshVectorWindBarbRenderer::drawVector( const QgsPointXY &lineStart, dou
   const double centerRadius = d;
   const double zeroCircleRadius = 2 * d;
   const double barbLength = 8 * d + pen.widthF();
-  const double barbAngle = isNorthHemisphere ? 135 : -135;
+  const double barbAngle = 135;
   const double barbOffset = 2 * d + pen.widthF();
+  const int sign = isNorthHemisphere ? 1 : -1;
 
   // Determine the angle of the vector, counter-clockwise, from east
   // (and associated trigs)
@@ -627,7 +628,7 @@ void QgsMeshVectorWindBarbRenderer::drawVector( const QgsPointXY &lineStart, dou
     // When first barb is a '10', we want to draw the shaft and barb as a single polyline for a proper join
     const QVector< QPointF > pts{ lineStart.toQPointF(),
                                   lineEnd.toQPointF(),
-                                  nextLineOrigin.project( barbLength, azimuth + barbAngle ).toQPointF() };
+                                  nextLineOrigin.project( barbLength, azimuth + barbAngle * sign ).toQPointF() };
     mContext.painter()->drawPolyline( pts );
     nextLineOrigin = nextLineOrigin.project( barbOffset, azimuth );
     knots -= 10;
@@ -645,7 +646,7 @@ void QgsMeshVectorWindBarbRenderer::drawVector( const QgsPointXY &lineStart, dou
   while ( knots > 47.5 )
   {
     const QVector< QPointF > pts{ nextLineOrigin.toQPointF(),
-                                  nextLineOrigin.project( barbLength / 1.414, azimuth + 90 ).toQPointF(),
+                                  nextLineOrigin.project( barbLength / 1.414, azimuth + 90 * sign ).toQPointF(),
                                   nextLineOrigin.project( barbLength / 1.414, azimuth ).toQPointF() };
     mContext.painter()->drawPolygon( pts );
     knots -= 50;
@@ -660,7 +661,7 @@ void QgsMeshVectorWindBarbRenderer::drawVector( const QgsPointXY &lineStart, dou
   // draw large barbs (10)
   while ( knots > 7.5 )
   {
-    mContext.painter()->drawLine( nextLineOrigin.toQPointF(), nextLineOrigin.project( barbLength, azimuth + barbAngle ).toQPointF() );
+    mContext.painter()->drawLine( nextLineOrigin.toQPointF(), nextLineOrigin.project( barbLength, azimuth + barbAngle * sign ).toQPointF() );
     nextLineOrigin = nextLineOrigin.project( barbOffset, azimuth );
     knots -= 10;
   }
@@ -672,7 +673,7 @@ void QgsMeshVectorWindBarbRenderer::drawVector( const QgsPointXY &lineStart, dou
     if ( nextLineOrigin == lineEnd )
       nextLineOrigin = nextLineOrigin.project( barbLength / 2, azimuth );
 
-    mContext.painter()->drawLine( nextLineOrigin.toQPointF(), nextLineOrigin.project( barbLength / 2, azimuth + barbAngle ).toQPointF() );
+    mContext.painter()->drawLine( nextLineOrigin.toQPointF(), nextLineOrigin.project( barbLength / 2, azimuth + barbAngle * sign ).toQPointF() );
   }
 }
 ///@endcond