fix for different vector rendering types

qgis · Oct 25, 2018 · 20a205d · 20a205d
1 parent b0bd629
commit 20a205d
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Showing 2 changed files with 41 additions and 8 deletions.
diff --git a/src/core/mesh/qgsmeshvectorrenderer.cpp b/src/core/mesh/qgsmeshvectorrenderer.cpp
@@ -74,7 +74,7 @@ QgsMeshVectorRenderer::QgsMeshVectorRenderer( const QgsTriangularMesh &m,
   // we need to expand out the extent so that it includes
   // arrows which start or end up outside of the
   // actual visible extent
-  double extension = context.convertToMapUnits( mMaxMag, QgsUnitTypes::RenderPixels );
+  double extension = context.convertToMapUnits( calcExtentBufferSize(), QgsUnitTypes::RenderPixels );
   mBufferedExtent.setXMinimum( mBufferedExtent.xMinimum() - extension );
   mBufferedExtent.setXMaximum( mBufferedExtent.xMaximum() + extension );
   mBufferedExtent.setYMinimum( mBufferedExtent.yMinimum() - extension );
@@ -200,6 +200,39 @@ bool QgsMeshVectorRenderer::calcVectorLineEnd(
   return false; //success
 }
 
+double QgsMeshVectorRenderer::calcExtentBufferSize() const
+{
+  double buffer;
+  switch ( mCfg.shaftLengthMethod() )
+  {
+    case QgsMeshRendererVectorSettings::ArrowScalingMethod::MinMax:
+    {
+      buffer = mContext.convertToPainterUnits( mCfg.maxShaftLength(),
+               QgsUnitTypes::RenderUnit::RenderMillimeters );
+      break;
+    }
+    case QgsMeshRendererVectorSettings::ArrowScalingMethod::Scaled:
+    {
+      buffer = mCfg.scaleFactor() * mMaxMag;
+      break;
+    }
+    case QgsMeshRendererVectorSettings::ArrowScalingMethod::Fixed:
+    {
+      buffer = mContext.convertToPainterUnits( mCfg.fixedShaftLength(),
+               QgsUnitTypes::RenderUnit::RenderMillimeters );
+      break;
+    }
+  }
+
+  if ( mCfg.filterMax() >= 0 && buffer > mCfg.filterMax() )
+    buffer = mCfg.filterMax();
+
+  if ( buffer < 0.0 )
+    buffer = 0.0;
+
+  return buffer;
+}
+
 
 void QgsMeshVectorRenderer::drawVectorDataOnVertices( const QList<int> &trianglesInExtent )
 {

diff --git a/src/core/mesh/qgsmeshvectorrenderer.h b/src/core/mesh/qgsmeshvectorrenderer.h
@@ -83,6 +83,13 @@ class QgsMeshVectorRenderer
                             double magnitude //in
                           );
 
+    /**
+     * Calculates the buffer size
+     * needed to draw arrows which have
+     * start or end point outside the
+     * visible canvas extent (in pixels)
+     */
+    double calcExtentBufferSize() const;
 
     const QgsTriangularMesh &mTriangularMesh;
     const QVector<double> &mDatasetValuesX;
@@ -94,13 +101,6 @@ class QgsMeshVectorRenderer
     const QgsMeshRendererVectorSettings &mCfg;
     bool mDataOnVertices = true;
     QSize mOutputSize;
-
-    /**
-     * Canvas extent buffered by vector maximum magnitude
-     * Needed to draw arrows which have
-     * start or end point outside the
-     * visible canvas extent
-     */
     QgsRectangle mBufferedExtent;
 };