Perform level 3 data moment remapping when smoothing

scwx-qt/source/scwx/qt/view/level3_product_view.cpp

@@ -485,6 +485,50 @@ void Level3ProductView::UpdateColorTableLut()
    Q_EMIT ColorTableLutUpdated();
 }
 
+std::uint8_t Level3ProductView::ComputeEdgeValue() const
+{
+   std::uint8_t edgeValue = 0;
+
+   std::shared_ptr<wsr88d::rpg::ProductDescriptionBlock> descriptionBlock =
+      p->graphicMessage_->description_block();
+
+   const float offset = descriptionBlock->offset();
+   const float scale  = descriptionBlock->scale();
+
+   switch (p->category_)
+   {
+   case common::Level3ProductCategory::Velocity:
+      edgeValue = (scale > 0.0f) ? (-offset / scale) : -offset;
+      break;
+
+   case common::Level3ProductCategory::DifferentialReflectivity:
+      edgeValue = -offset;
+      break;
+
+   case common::Level3ProductCategory::SpectrumWidth:
+   case common::Level3ProductCategory::SpecificDifferentialPhase:
+      edgeValue = 2;
+      break;
+
+   case common::Level3ProductCategory::CorrelationCoefficient:
+      edgeValue = static_cast<std::uint8_t>(
+         std::max<std::uint16_t>(255, descriptionBlock->number_of_levels()));
+      break;
+
+   case common::Level3ProductCategory::Reflectivity:
+   case common::Level3ProductCategory::StormRelativeVelocity:
+   case common::Level3ProductCategory::VerticallyIntegratedLiquid:
+   case common::Level3ProductCategory::EchoTops:
+   case common::Level3ProductCategory::HydrometeorClassification:
+   case common::Level3ProductCategory::PrecipitationAccumulation:
+   default:
+      edgeValue = 0;
+      break;
+   }
+
+   return edgeValue;
+}
+
 std::optional<wsr88d::DataLevelCode>
 Level3ProductView::GetDataLevelCode(std::uint16_t level) const
 {

scwx-qt/source/scwx/qt/view/level3_product_view.hpp

@@ -58,6 +58,8 @@ protected:
    void DisconnectRadarProductManager() override;
    void UpdateColorTableLut() override;
 
+   std::uint8_t ComputeEdgeValue() const;
+
 private:
    class Impl;
    std::unique_ptr<Impl> p;

scwx-qt/source/scwx/qt/view/level3_radial_view.cpp

@@ -47,6 +47,8 @@ public:
       const std::shared_ptr<wsr88d::rpg::GenericRadialDataPacket>& radialData,
       bool smoothingEnabled);
 
+   inline std::uint8_t RemapDataMoment(std::uint8_t dataMoment) const;
+
    Level3RadialView* self_;
 
    boost::asio::thread_pool threadPool_ {1u};
@@ -54,6 +56,7 @@ public:
    std::vector<float>        coordinates_ {};
    std::vector<float>        vertices_ {};
    std::vector<std::uint8_t> dataMoments8_ {};
+   std::uint8_t              edgeValue_ {};
 
    std::shared_ptr<wsr88d::rpg::GenericRadialDataPacket> lastRadialData_ {};
    bool lastSmoothingEnabled_ {false};
@@ -347,6 +350,10 @@ void Level3RadialView::ComputeSweep()
       // are skipping the radar site origin. The end gate is unaffected, as
       // we need to draw one less data point.
       ++startGate;
+
+      // For most products other than reflectivity, the edge should not go to
+      // the bottom of the color table
+      p->edgeValue_ = ComputeEdgeValue();
    }
 
    for (std::uint16_t radial = 0; radial < radialData->number_of_radials();
@@ -401,12 +408,12 @@ void Level3RadialView::ComputeSweep()
             }
 
             // The order must match the store vertices section below
-            dataMoments8[mIndex++] = dm1;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm1);
-            dataMoments8[mIndex++] = dm2;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm2);
-            dataMoments8[mIndex++] = dm4;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm4);
-            dataMoments8[mIndex++] = dm1;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm1);
-            dataMoments8[mIndex++] = dm3;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm3);
-            dataMoments8[mIndex++] = dm4;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm4);
          }
          else
          {
@@ -492,6 +499,19 @@ void Level3RadialView::ComputeSweep()
    Q_EMIT SweepComputed();
 }
 
+std::uint8_t
+Level3RadialView::Impl::RemapDataMoment(std::uint8_t dataMoment) const
+{
+   if (dataMoment != 0)
+   {
+      return dataMoment;
+   }
+   else
+   {
+      return edgeValue_;
+   }
+}
+
 void Level3RadialView::Impl::ComputeCoordinates(
    const std::shared_ptr<wsr88d::rpg::GenericRadialDataPacket>& radialData,
    bool smoothingEnabled)

scwx-qt/source/scwx/qt/view/level3_raster_view.cpp

@@ -33,10 +33,13 @@ public:
    }
    ~Level3RasterViewImpl() { threadPool_.join(); };
 
+   inline std::uint8_t RemapDataMoment(std::uint8_t dataMoment) const;
+
    boost::asio::thread_pool threadPool_ {1u};
 
-   std::vector<float>   vertices_;
+   std::vector<float>        vertices_ {};
-   std::vector<uint8_t> dataMoments8_;
+   std::vector<std::uint8_t> dataMoments8_ {};
+   std::uint8_t              edgeValue_ {};
 
    std::shared_ptr<wsr88d::rpg::RasterDataPacket> lastRasterData_ {};
    bool                                           lastSmoothingEnabled_ {false};
@@ -310,6 +313,13 @@ void Level3RasterView::ComputeSweep()
                                    rasterData->number_of_rows() - 1 :
                                    rasterData->number_of_rows();
 
+   if (smoothingEnabled)
+   {
+      // For most products other than reflectivity, the edge should not go to
+      // the bottom of the color table
+      p->edgeValue_ = ComputeEdgeValue();
+   }
+
    for (std::size_t row = 0; row < rowCount; ++row)
    {
       const std::size_t nextRow =
@@ -364,12 +374,12 @@ void Level3RasterView::ComputeSweep()
             }
 
             // The order must match the store vertices section below
-            dataMoments8[mIndex++] = dm1;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm1);
-            dataMoments8[mIndex++] = dm2;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm2);
-            dataMoments8[mIndex++] = dm4;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm4);
-            dataMoments8[mIndex++] = dm1;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm1);
-            dataMoments8[mIndex++] = dm3;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm3);
-            dataMoments8[mIndex++] = dm4;
+            dataMoments8[mIndex++] = p->RemapDataMoment(dm4);
          }
 
          // Store vertices
@@ -411,6 +421,19 @@ void Level3RasterView::ComputeSweep()
    Q_EMIT SweepComputed();
 }
 
+std::uint8_t
+Level3RasterViewImpl::RemapDataMoment(std::uint8_t dataMoment) const
+{
+   if (dataMoment != 0)
+   {
+      return dataMoment;
+   }
+   else
+   {
+      return edgeValue_;
+   }
+}
+
 std::optional<std::uint16_t>
 Level3RasterView::GetBinLevel(const common::Coordinate& coordinate) const
 {