adding finer grain control over color bar and scalar field label

vtkm/rendering/ColorBarAnnotation.cxx

@@ -19,6 +19,7 @@
 //============================================================================
 
 #include <vtkm/rendering/ColorBarAnnotation.h>
+#include <vtkm/rendering/TextAnnotationScreen.h>
 
 namespace vtkm
 {
@@ -27,12 +28,32 @@ namespace rendering
 
 ColorBarAnnotation::ColorBarAnnotation()
 {
+  vtkm::Bounds bounds(vtkm::Range(-0.88, +0.88), vtkm::Range(+0.87, +0.92), vtkm::Range(0, 0));
+  Position = bounds;
+  Horizontal = true;
+  FieldName = "";
 }
 
 ColorBarAnnotation::~ColorBarAnnotation()
 {
 }
 
+void ColorBarAnnotation::SetFieldName(const std::string& fieldName)
+{
+  FieldName = fieldName;
+}
+
+void ColorBarAnnotation::SetPosition(const vtkm::Bounds& position)
+{
+  Position = position;
+  vtkm::Float64 x = Position.X.Length();
+  vtkm::Float64 y = Position.Y.Length();
+  if (x > y)
+    Horizontal = true;
+  else
+    Horizontal = false;
+}
+
 void ColorBarAnnotation::SetRange(const vtkm::Range& range, vtkm::IdComponent numTicks)
 {
   std::vector<vtkm::Float64> positions, proportions;
@@ -52,17 +73,50 @@ void ColorBarAnnotation::Render(const vtkm::rendering::Camera& camera,
                                 const vtkm::rendering::WorldAnnotator& worldAnnotator,
                                 vtkm::rendering::Canvas& canvas)
 {
-  vtkm::Bounds bounds(vtkm::Range(-0.88, +0.88), vtkm::Range(+0.87, +0.92), vtkm::Range(0, 0));
 
-  canvas.AddColorBar(bounds, this->ColorTable, true);
+  canvas.AddColorBar(Position, this->ColorTable, Horizontal);
 
   this->Axis.SetColor(canvas.GetForegroundColor());
   this->Axis.SetLineWidth(1);
-  this->Axis.SetScreenPosition(bounds.X.Min, bounds.Y.Min, bounds.X.Max, bounds.Y.Min);
-  this->Axis.SetMajorTickSize(0, .02, 1.0);
+
+  if (Horizontal)
+  {
+    this->Axis.SetScreenPosition(Position.X.Min, Position.Y.Min, Position.X.Max, Position.Y.Min);
+    this->Axis.SetLabelAlignment(TextAnnotation::HCenter, TextAnnotation::Top);
+    this->Axis.SetMajorTickSize(0, .02, 1.0);
+  }
+  else
+  {
+    this->Axis.SetScreenPosition(Position.X.Min, Position.Y.Min, Position.X.Min, Position.Y.Max);
+    this->Axis.SetLabelAlignment(TextAnnotation::Right, TextAnnotation::VCenter);
+    this->Axis.SetMajorTickSize(.02, 0.0, 1.0);
+  }
+
   this->Axis.SetMinorTickSize(0, 0, 0); // no minor ticks
-  this->Axis.SetLabelAlignment(TextAnnotation::HCenter, TextAnnotation::Top);
   this->Axis.Render(camera, worldAnnotator, canvas);
+
+  if (FieldName != "")
+  {
+    vtkm::Vec<vtkm::Float32, 2> labelPos;
+    if (Horizontal)
+    {
+      labelPos[0] = vtkm::Float32(Position.X.Min);
+      labelPos[1] = vtkm::Float32(Position.Y.Max);
+    }
+    else
+    {
+      labelPos[0] = vtkm::Float32(Position.X.Min - 0.07);
+      labelPos[1] = vtkm::Float32(Position.Y.Max + 0.03);
+    }
+
+    vtkm::rendering::TextAnnotationScreen var(FieldName,
+                                              canvas.GetForegroundColor(),
+                                              .045f, // font scale
+                                              labelPos,
+                                              0.f); // rotation
+
+    var.Render(camera, worldAnnotator, canvas);
+  }
 }
 }
 } // namespace vtkm::rendering

vtkm/rendering/ColorBarAnnotation.h

@@ -38,6 +38,9 @@ class VTKM_RENDERING_EXPORT ColorBarAnnotation
 protected:
   vtkm::rendering::ColorTable ColorTable;
   vtkm::rendering::AxisAnnotation2D Axis;
+  vtkm::Bounds Position;
+  bool Horizontal;
+  std::string FieldName;
 
 public:
   ColorBarAnnotation();
@@ -50,14 +53,22 @@ public:
     this->ColorTable = colorTable;
   }
 
+  VTKM_CONT
   void SetRange(const vtkm::Range& range, vtkm::IdComponent numTicks);
 
+  VTKM_CONT
+  void SetFieldName(const std::string& fieldName);
+
   VTKM_CONT
   void SetRange(vtkm::Float64 l, vtkm::Float64 h, vtkm::IdComponent numTicks)
   {
     this->SetRange(vtkm::Range(l, h), numTicks);
   }
 
+
+  VTKM_CONT
+  void SetPosition(const vtkm::Bounds& position);
+
   virtual void Render(const vtkm::rendering::Camera& camera,
                       const vtkm::rendering::WorldAnnotator& worldAnnotator,
                       vtkm::rendering::Canvas& canvas);

vtkm/rendering/View2D.cxx

@@ -102,6 +102,7 @@ void View2D::RenderScreenAnnotations()
   if (scene.GetNumberOfActors() > 0)
   {
     //this->ColorBarAnnotation.SetAxisColor(vtkm::rendering::Color(1,1,1));
+    this->ColorBarAnnotation.SetFieldName(scene.GetActor(0).GetScalarField().GetName());
     this->ColorBarAnnotation.SetRange(
       scene.GetActor(0).GetScalarRange().Min, scene.GetActor(0).GetScalarRange().Max, 5);
     this->ColorBarAnnotation.SetColorTable(scene.GetActor(0).GetColorTable());

vtkm/rendering/View3D.cxx

@@ -69,6 +69,7 @@ void View3D::RenderScreenAnnotations()
   if (this->GetScene().GetNumberOfActors() > 0)
   {
     //this->ColorBarAnnotation.SetAxisColor(vtkm::rendering::Color(1,1,1));
+    this->ColorBarAnnotation.SetFieldName(this->GetScene().GetActor(0).GetScalarField().GetName());
     this->ColorBarAnnotation.SetRange(this->GetScene().GetActor(0).GetScalarRange(), 5);
     this->ColorBarAnnotation.SetColorTable(this->GetScene().GetActor(0).GetColorTable());
     this->ColorBarAnnotation.Render(