/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkScalarBarActor.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
/**
 * @class   vtkScalarBarActor
 * @brief   Create a scalar bar with labels
 *
 * vtkScalarBarActor creates a scalar bar with tick marks. A scalar
 * bar is a legend that indicates to the viewer the correspondence between
 * color value and data value. The legend consists of a rectangular bar
 * made of rectangular pieces each colored a constant value. Since
 * vtkScalarBarActor is a subclass of vtkActor2D, it is drawn in the image
 * plane (i.e., in the renderer's viewport) on top of the 3D graphics window.
 *
 * To use vtkScalarBarActor you must associate a vtkScalarsToColors (or
 * subclass) with it. The lookup table defines the colors and the
 * range of scalar values used to map scalar data.  Typically, the
 * number of colors shown in the scalar bar is not equal to the number
 * of colors in the lookup table, in which case sampling of
 * the lookup table is performed.
 *
 * Other optional capabilities include specifying the fraction of the
 * viewport size (both x and y directions) which will control the size
 * of the scalar bar and the number of tick labels. The actual position
 * of the scalar bar on the screen is controlled by using the
 * vtkActor2D::SetPosition() method (by default the scalar bar is
 * centered in the viewport).  Other features include the ability to
 * orient the scalar bar horizontally of vertically and controlling
 * the format (printf style) with which to print the labels on the
 * scalar bar. Also, the vtkScalarBarActor's property is applied to
 * the scalar bar and annotations (including layer, and
 * compositing operator).
 *
 * Set the text property/attributes of the title and the labels through the
 * vtkTextProperty objects associated to this actor.
 *
 * @warning
 * If a vtkLogLookupTable is specified as the lookup table to use, then the
 * labels are created using a logarithmic scale.
 *
 * @sa
 * vtkActor2D vtkTextProperty vtkTextMapper vtkPolyDataMapper2D
*/

#ifndef vtkScalarBarActor_h
#define vtkScalarBarActor_h

#include "vtkRenderingAnnotationModule.h" // For export macro
#include "vtkActor2D.h"

class vtkColor3ub;
class vtkPolyData;
class vtkPolyDataMapper2D;
class vtkProperty2D;
class vtkScalarsToColors;
class vtkScalarBarActorInternal;
class vtkTextActor;
class vtkTextMapper;
class vtkTextProperty;
class vtkTexture;
class vtkTexturedActor2D;

#define VTK_ORIENT_HORIZONTAL 0
#define VTK_ORIENT_VERTICAL 1

class VTKRENDERINGANNOTATION_EXPORT vtkScalarBarActor : public vtkActor2D
{
public:
  vtkTypeMacro(vtkScalarBarActor, vtkActor2D);
  void PrintSelf(ostream& os, vtkIndent indent) override;

  /**
   * Instantiate object with 64 maximum colors; 5 labels; %%-#6.3g label
   * format, no title, and vertical orientation. The initial scalar bar
   * size is (0.05 x 0.8) of the viewport size.
   */
  static vtkScalarBarActor* New();

  //@{
  /**
   * Draw the scalar bar and annotation text to the screen.
   */
  int RenderOpaqueGeometry(vtkViewport* viewport) override;
  int RenderTranslucentPolygonalGeometry(vtkViewport*) override { return 0; };
  int RenderOverlay(vtkViewport* viewport) override;
  //@}

  /**
   * Does this prop have some translucent polygonal geometry?
   */
  int HasTranslucentPolygonalGeometry() override;

  /**
   * Release any graphics resources that are being consumed by this actor.
   * The parameter window could be used to determine which graphic
   * resources to release.
   */
  void ReleaseGraphicsResources(vtkWindow*) override;

  /**
   * Fills rect with the dimensions of the scalar bar in viewport coordinates.
   * Only the color bar is considered -- text labels are not considered.
   * rect is {xmin, xmax, width, height}
   */
  virtual void GetScalarBarRect(int rect[4], vtkViewport* viewport);

  //@{
  /**
   * Set/Get the lookup table to use. The lookup table specifies the number
   * of colors to use in the table (if not overridden), the scalar range,
   * and any annotated values.
   * Annotated values are rendered using vtkTextActor.
   */
  virtual void SetLookupTable(vtkScalarsToColors*);
  vtkGetObjectMacro(LookupTable, vtkScalarsToColors);
  //@}

  //@{
  /**
   * Should be display the opacity as well. This is displayed by changing
   * the opacity of the scalar bar in accordance with the opacity of the
   * given color. For clarity, a texture grid is placed in the background
   * if Opacity is ON. You might also want to play with SetTextureGridWith
   * in that case. [Default: off]
   */
  vtkSetMacro(UseOpacity, int);
  vtkGetMacro(UseOpacity, int);
  vtkBooleanMacro(UseOpacity, int);
  //@}

  //@{
  /**
   * Set/Get the maximum number of scalar bar segments to show. This may
   * differ from the number of colors in the lookup table, in which case
   * the colors are samples from the lookup table.
   */
  vtkSetClampMacro(MaximumNumberOfColors, int, 2, VTK_INT_MAX);
  vtkGetMacro(MaximumNumberOfColors, int);
  //@}

  //@{
  /**
   * Set/Get the number of tick labels to show.
   */
  vtkSetClampMacro(NumberOfLabels, int, 0, 64);
  vtkGetMacro(NumberOfLabels, int);
  //@}

  //@{
  /**
   * Control the orientation of the scalar bar.
   */
  vtkSetClampMacro(Orientation, int, VTK_ORIENT_HORIZONTAL, VTK_ORIENT_VERTICAL);
  vtkGetMacro(Orientation, int);
  void SetOrientationToHorizontal()
       {this->SetOrientation(VTK_ORIENT_HORIZONTAL);}
  void SetOrientationToVertical() {this->SetOrientation(VTK_ORIENT_VERTICAL);}
  //@}

  //@{
  /**
   * Set/Get the title text property.
   */
  virtual void SetTitleTextProperty(vtkTextProperty* p);
  vtkGetObjectMacro(TitleTextProperty, vtkTextProperty);
  //@}

  //@{
  /**
   * Set/Get the labels text property.
   */
  virtual void SetLabelTextProperty(vtkTextProperty* p);
  vtkGetObjectMacro(LabelTextProperty, vtkTextProperty);
  //@}

  //@{
  /**
   * Set/Get the annotation text property.
   */
  virtual void SetAnnotationTextProperty(vtkTextProperty* p);
  vtkGetObjectMacro(AnnotationTextProperty, vtkTextProperty);
  //@}

  //@{
  /**
   * Set/Get the format with which to print the labels on the scalar
   * bar.
   */
  vtkSetStringMacro(LabelFormat);
  vtkGetStringMacro(LabelFormat);
  //@}

  //@{
  /**
   * Set/Get the title of the scalar bar actor,
   */
  vtkSetStringMacro(Title);
  vtkGetStringMacro(Title);
  //@}

  //@{
  /**
   * Set/Get the title for the component that is selected,
   */
  vtkSetStringMacro(ComponentTitle);
  vtkGetStringMacro(ComponentTitle);
  //@}

  /**
   * Shallow copy of a scalar bar actor. Overloads the virtual vtkProp method.
   */
  void ShallowCopy(vtkProp* prop) override;

  //@{
  /**
   * Set the width of the texture grid. Used only if UseOpacity is ON.
   */
  vtkSetMacro(TextureGridWidth, double);
  vtkGetMacro(TextureGridWidth, double);
  //@}

  //@{
  /**
   * Get the texture actor.. you may want to change some properties on it
   */
  vtkGetObjectMacro(TextureActor, vtkTexturedActor2D);
  //@}

  enum { PrecedeScalarBar = 0, SucceedScalarBar };

  //@{
  /**
   * Should the title and tick marks precede the scalar bar or succeed it?
   * This is measured along the viewport coordinate direction perpendicular
   * to the long axis of the scalar bar, not the reading direction.
   * Thus, succeed implies the that the text is above scalar bar if
   * the orientation is horizontal or right of scalar bar if the orientation
   * is vertical. Precede is the opposite.
   */
  vtkSetClampMacro(TextPosition, int, PrecedeScalarBar, SucceedScalarBar);
  vtkGetMacro(TextPosition, int);
  virtual void SetTextPositionToPrecedeScalarBar()
    { this->SetTextPosition(vtkScalarBarActor::PrecedeScalarBar); }
  virtual void SetTextPositionToSucceedScalarBar()
    { this->SetTextPosition(vtkScalarBarActor::SucceedScalarBar); }
  //@}

  //@{
  /**
   * Set/Get the maximum width and height in pixels. Specifying the size as
   * a relative fraction of the viewport can sometimes undesirably stretch
   * the size of the actor too much. These methods allow the user to set
   * bounds on the maximum size of the scalar bar in pixels along any
   * direction. Defaults to unbounded.
   */
  vtkSetMacro(MaximumWidthInPixels, int);
  vtkGetMacro(MaximumWidthInPixels, int);
  vtkSetMacro(MaximumHeightInPixels, int);
  vtkGetMacro(MaximumHeightInPixels, int);
  //@}

  //@{
  /**
   * Set/get the padding between the scalar bar and the text annotations.
   * This space is used to draw leader lines.
   * The default is 8 pixels.
   */
  vtkSetMacro(AnnotationLeaderPadding, double);
  vtkGetMacro(AnnotationLeaderPadding, double);
  //@}

  //@{
  /**
   * Set/get whether text annotations should be rendered or not.
   * Currently, this only affects rendering when \a IndexedLookup is true.
   * The default is true.
   */
  vtkSetMacro(DrawAnnotations, int);
  vtkGetMacro(DrawAnnotations, int);
  vtkBooleanMacro(DrawAnnotations, int);
  //@}

  //@{
  /**
   * Set/get whether the NaN annotation should be rendered or not.
   * This only affects rendering when \a DrawAnnotations is true.
   * The default is false.
   */
  vtkSetMacro(DrawNanAnnotation, int);
  vtkGetMacro(DrawNanAnnotation, int);
  vtkBooleanMacro(DrawNanAnnotation, int);
  //@}

  //@{
  /**
   * Set/get whether the Below range swatch should be rendered or not.
   * This only affects rendering when \a DrawAnnotations is true.
   * The default is false.
   */
  vtkSetMacro(DrawBelowRangeSwatch, bool);
  vtkGetMacro(DrawBelowRangeSwatch, bool);
  vtkBooleanMacro(DrawBelowRangeSwatch, bool);
  //@}

  //@{
  /**
   * Set/get the annotation text for "Below Range" values.
   */
  vtkSetStringMacro(BelowRangeAnnotation);
  vtkGetStringMacro(BelowRangeAnnotation);
  //@}

  //@{
  /**
   * Set/get whether the Above range swatch should be rendered or not.
   * This only affects rendering when \a DrawAnnotations is true.
   * The default is false.
   */
  vtkSetMacro(DrawAboveRangeSwatch, bool);
  vtkGetMacro(DrawAboveRangeSwatch, bool);
  vtkBooleanMacro(DrawAboveRangeSwatch, bool);
  //@}

  //@{
  /**
   * Set/get the annotation text for "Above Range Swatch" values.
   */
  vtkSetStringMacro(AboveRangeAnnotation);
  vtkGetStringMacro(AboveRangeAnnotation);
  //@}
  //@{
  /**
   * Set/get how leader lines connecting annotations to values should be colored.

   * When true, leader lines are all the same color (and match the LabelTextProperty color).
   * When false, leader lines take on the color of the value they correspond to.
   * This only affects rendering when \a DrawAnnotations is true.
   * The default is false.
   */
  vtkSetMacro(FixedAnnotationLeaderLineColor, int);
  vtkGetMacro(FixedAnnotationLeaderLineColor, int);
  vtkBooleanMacro(FixedAnnotationLeaderLineColor, int);
  //@}

  //@{
  /**
   * Set/get the annotation text for "NaN" values.
   */
  vtkSetStringMacro(NanAnnotation);
  vtkGetStringMacro(NanAnnotation);
  //@}

  //@{
  /**
   * Set/get whether annotation labels should be scaled with the viewport.

   * The default value is 0 (no scaling).
   * If non-zero, the vtkTextActor instances used to render annotation
   * labels will have their TextScaleMode set to viewport-based scaling,
   * which nonlinearly scales font size with the viewport size.
   */
  vtkSetMacro(AnnotationTextScaling, int);
  vtkGetMacro(AnnotationTextScaling, int);
  vtkBooleanMacro(AnnotationTextScaling, int);
  //@}

  //@{
  /**
   * Set/Get whether a background should be drawn around the scalar bar.
   * Default is off.
   */
  vtkSetMacro(DrawBackground, int);
  vtkGetMacro(DrawBackground, int);
  vtkBooleanMacro(DrawBackground, int);
  //@}

  //@{
  /**
   * Set/Get whether a frame should be drawn around the scalar bar.
   * Default is off.
   */
  vtkSetMacro(DrawFrame, int);
  vtkGetMacro(DrawFrame, int);
  vtkBooleanMacro(DrawFrame, int);
  //@}

  //@{
  /**
   * Set/Get whether the color bar should be drawn. If off, only the tickmarks
   * and text will be drawn. Default is on.
   */
  vtkSetMacro(DrawColorBar, int);
  vtkGetMacro(DrawColorBar, int);
  vtkBooleanMacro(DrawColorBar, int);
  //@}

  //@{
  /**
   * Set/Get whether the tick labels should be drawn. Default is on.
   */
  vtkSetMacro(DrawTickLabels, int);
  vtkGetMacro(DrawTickLabels, int);
  vtkBooleanMacro(DrawTickLabels, int);
  //@}

  //@{
  /**
   * Set/Get the background property.
   */
  virtual void SetBackgroundProperty(vtkProperty2D* p);
  vtkGetObjectMacro(BackgroundProperty, vtkProperty2D);
  //@}

  //@{
  /**
   * Set/Get the frame property.
   */
  virtual void SetFrameProperty(vtkProperty2D* p);
  vtkGetObjectMacro(FrameProperty, vtkProperty2D);
  //@}

  //@{
  /**
   * Set/get the amount of padding around text boxes.
   * The default is 1 pixel.
   */
  vtkGetMacro(TextPad, int);
  vtkSetMacro(TextPad, int);
  //@}

  //@{
  /**
   * Set/get the margin in pixels, between the title and the bar,
   * when the \a Orientation is vertical.
   * The default is 0 pixels.
   */
  vtkGetMacro(VerticalTitleSeparation, int);
  vtkSetMacro(VerticalTitleSeparation, int);
  //@}

  //@{
  /**
   * Set/get the thickness of the color bar relative to the widget frame.
   * The default is 0.375 and must always be in the range ]0, 1[.
   */
  vtkGetMacro(BarRatio, double);
  vtkSetClampMacro(BarRatio, double, 0., 1.);
  //@}

  //@{
  /**
   * Set/get the ratio of the title height to the tick label height
   * (used only when the \a Orientation is horizontal).
   * The default is 0.5, which attempts to make the labels and title
   * the same size. This must be a number in the range ]0, 1[.
   */
  vtkGetMacro(TitleRatio, double);
  vtkSetClampMacro(TitleRatio, double, 0., 1.);
  //@}

  //@{
  /**
   * Set/Get whether the font size of title and labels is unconstrained. Default is off.
   * When it is constrained, the size of the scalar bar will constrained the font size
   * When it is not, the size of the font will always be respected
   */
  vtkSetMacro(UnconstrainedFontSize, bool);
  vtkGetMacro(UnconstrainedFontSize, bool);
  vtkBooleanMacro(UnconstrainedFontSize, bool);
  //@}

protected:
  vtkScalarBarActor();
  ~vtkScalarBarActor() override;

  /**
   * Called from within \a RenderOpaqueGeometry when the internal state
   * members need to be updated before rendering.

   * This method invokes many virtual methods that first lay out the
   * scalar bar and then use the layout to position actors and create
   * datasets used to represent the scalar bar.
   * Specifically, it invokes: FreeLayoutStorage, ComputeFrame,
   * ComputeScalarBarThickness, LayoutNanSwatch, PrepareTitleText,
   * LayoutTitle, ComputeScalarBarLength, LayoutTicks, and LayoutAnnotations
   * to perform the layout step.
   * Then, it invokes ConfigureAnnotations, ConfigureFrame,
   * ConfigureScalarBar, ConfigureTitle, ConfigureTicks, and
   * ConfigureNanSwatch to create and position actors used to render
   * portions of the scalar bar.

   * By overriding one or more of these virtual methods, subclasses
   * may change the appearance of the scalar bar.

   * In the layout phase, text actors must have their text properties
   * and input strings updated, but the position of the actors should
   * not be set or relied upon as subsequent layout steps may alter
   * their placement.
   */
  virtual void RebuildLayout(vtkViewport* viewport);

  /**
   * Calls RebuildLayout if it is needed such as when
   * positions etc have changed. Return 1 on success
   * zero on error
   */
  virtual int RebuildLayoutIfNeeded(vtkViewport* viewport);


  /**
   * Free internal storage used by the previous layout.
   */
  virtual void FreeLayoutStorage();

  /**
   * If the scalar bar should be inset into a frame or rendered with a
   * solid background, this method will inset the outermost scalar bar
   * rectangle by a small amount to avoid having the scalar bar
   * illustration overlap any edges.

   * This method must set the frame coordinates (this->P->Frame).
   */
  virtual void ComputeFrame();

  /**
   * Determine how thick the scalar bar should be (on an axis perpendicular
   * to the direction in which scalar values vary).

   * This method must set the scalar bar thickness
   * (this->P->ScalarBarBox.Size[0]).
   * It may depend on layout performed by ComputeFrame
   * (i.e., the frame coordinates in this->P->Frame).
   */
  virtual void ComputeScalarBarThickness();

  /**
   * Compute a correct SwatchPad
   */
  virtual void ComputeSwatchPad();

  // This method must set this->P->NanSwatchSize and this->P->NanBox.
  // It may depend on layout performed by ComputeScalarBarThickness.
  virtual void LayoutNanSwatch();

  /**
   * Determine the size of the Below Range if it is to be rendered.

   * This method must set this->P->BelowSwatchSize and this->P->BelowBox.
   * It may depend on layout performed by ComputeScalarBarThickness.
   */
  virtual void LayoutBelowRangeSwatch();

  /**
   * Determine the size of the Above Range if it is to be rendered.

   * This method must set this->P->AboveBox.
   * It may depend on layout performed by ComputeScalarBarThickness.
   */
  virtual void LayoutAboveRangeSwatch();

  /**
   * Determine the position of the Above Range if it is to be rendered.

   * This method must set this->P->AboveRangeSize.
   * It may depend on layout performed by ComputeScalarBarLength.
   */
  virtual void LayoutAboveRangeSwatchPosn();

  /**
   * Set the title actor's input to the latest title (and subtitle) text.
   */
  virtual void PrepareTitleText();

  /**
   * Determine the position and size of the scalar bar title box.

   * This method must set this->P->TitleBox
   * It may depend on layout performed by LayoutNanSwatch.
   * If useTickBox is true, it should increase the target area
   * for the label to touch the tick box. It is called in this
   * way when the tick labels are small due to constraints other
   * than the title box.
   */
  virtual void LayoutTitle();

  /**
   * This method sets the title and tick-box size and position
   * for the UnconstrainedFontSize mode.
   */
  virtual void LayoutForUnconstrainedFont();

  /**
   * Determine how long the scalar bar should be (on an axis parallel
   * to the direction in which scalar values vary).

   * This method must set this->P->ScalarBarBox.Size[1] and should
   * estimate this->P->ScalarBarBox.Posn.
   * It may depend on layout performed by LayoutTitle.
   */
  virtual void ComputeScalarBarLength();

  /**
   * Determine the size and placement of any tick marks to be rendered.

   * This method must set this->P->TickBox.
   * It may depend on layout performed by ComputeScalarBarLength.

   * The default implementation creates exactly this->NumberOfLabels
   * tick marks, uniformly spaced on a linear or logarithmic scale.
   */
  virtual void LayoutTicks();

  /**
   * This method must lay out annotation text and leader lines so
   * they do not overlap.

   * This method must set this->P->AnnotationAnchors.
   * It may depend on layout performed by LayoutTicks.
   */
  virtual void LayoutAnnotations();

  /**
   * Generate/configure the annotation labels using the laid-out geometry.
   */
  virtual void ConfigureAnnotations();

  /**
   * Generate/configure the representation of the frame from laid-out geometry.
   */
  virtual void ConfigureFrame();

  /**
   * For debugging, add placement boxes to the frame polydata.
   */
  virtual void DrawBoxes();

  /**
   * Generate/configure the scalar bar representation from laid-out geometry.
   */
  virtual void ConfigureScalarBar();

  /**
   * Generate/configure the title actor using the laid-out geometry.
   */
  virtual void ConfigureTitle();

  /**
   * Generate/configure the tick-mark actors using the laid-out geometry.
   */
  virtual void ConfigureTicks();

  /**
   * Generate/configure the NaN swatch using the laid-out geometry.

   * Currently the NaN swatch is rendered by the same actor as the scalar bar.
   * This may change in the future.
   */
  virtual void ConfigureNanSwatch();

  /**
   * Generate/configure the above/below range swatch using the laid-out
   * geometry.
   */
  virtual void ConfigureAboveBelowRangeSwatch(bool above);

  /**
   * Subclasses may override this method to alter this->P->Labels, allowing
   * the addition and removal of annotations. The member maps viewport coordinates
   * along the long axis of the scalar bar to text (which may include MathText;
   * see vtkTextActor). It is a single-valued map, so you must perturb
   * the coordinate if you wish multiple labels to annotate the same position.
   * Each entry in this->P->Labels must have a matching entry in this->P->LabelColors.
   */
  virtual void EditAnnotations() { }

  /**
   * Compute the best size for the legend title.

   * This guarantees that the title will fit within the frame defined by Position and Position2.
   */
  virtual void SizeTitle(double* titleSize, int* size, vtkViewport* viewport);

  /**
   * Allocate actors for lookup table annotations and position them properly.
   */
  int MapAnnotationLabels(
    vtkScalarsToColors* lkup, double start, double delta, const double* range);

  /**
   * This method is called by \a ConfigureAnnotationLabels when Orientation is VTK_ORIENT_VERTICAL.
   */
  int PlaceAnnotationsVertically(
    double barX, double barY, double barWidth, double barHeight,
    double delta, double pad);
  /**
   * This method is called by \a ConfigureAnnotationLabels when Orientation is VTK_ORIENT_HORIZONTAL.
   */
  int PlaceAnnotationsHorizontally(
    double barX, double barY, double barWidth, double barHeight,
    double delta, double pad);

  /// User-changeable settings
  //@{
  int MaximumNumberOfColors;
  int NumberOfLabels;
  int NumberOfLabelsBuilt;
  int Orientation;
  int DrawBackground; // off by default
  int DrawFrame; // off by default
  int DrawColorBar; // on by default
  int DrawTickLabels; // on by default
  int DrawAnnotations;
  int DrawNanAnnotation;
  int AnnotationTextScaling; // off by default
  int FixedAnnotationLeaderLineColor;
  vtkProperty2D* BackgroundProperty;
  vtkProperty2D* FrameProperty;
  char* Title;
  char* ComponentTitle;
  char* LabelFormat;
  int UseOpacity; // off by default
  double TextureGridWidth;
  int TextPosition;
  char* NanAnnotation;
  char* BelowRangeAnnotation;
  char* AboveRangeAnnotation;
  double AnnotationLeaderPadding;
  int MaximumWidthInPixels;
  int MaximumHeightInPixels;
  int TextPad;
  int VerticalTitleSeparation;
  double BarRatio;
  double TitleRatio;
  bool UnconstrainedFontSize;  // off by default

  bool DrawBelowRangeSwatch;
  bool DrawAboveRangeSwatch;
  //@}

  /// Internal state used for rendering
  //@{
  vtkTimeStamp BuildTime; //!< Last time internal state changed.
  int LastSize[2]; //!< Projected size in viewport coordinates of last build.
  int LastOrigin[2]; //!< Projected origin (viewport coordinates) of last build.

  vtkScalarBarActorInternal* P; //!< Containers shared with subclasses

  vtkScalarsToColors* LookupTable; //!< The object this actor illustrates

  vtkTextProperty* TitleTextProperty; //!< Font for the legend title.
  vtkTextProperty* LabelTextProperty; //!< Font for tick labels.
  vtkTextProperty* AnnotationTextProperty; //!< Font for annotation labels.
  vtkTextActor* TitleActor; //!< The legend title text renderer.

  vtkPolyData* ScalarBar; //!< Polygon(s) colored by \a LookupTable.
  vtkPolyDataMapper2D* ScalarBarMapper; //!< Mapper for \a ScalarBar.
  vtkActor2D* ScalarBarActor; //!< Actor for \a ScalarBar.
  vtkPolyData* TexturePolyData; //!< Polygon colored when UseOpacity is true.
  vtkTexture* Texture; //!< Color data for \a TexturePolyData.
  vtkTexturedActor2D* TextureActor; //!< Actor for \a TexturePolyData.

  vtkPolyData* Background; //!< Polygon used to fill the background.
  vtkPolyDataMapper2D* BackgroundMapper; //!< Mapper for \a Background.
  vtkActor2D* BackgroundActor; //!< Actor for \a Background.

  vtkPolyData* Frame; //!< Polyline used to highlight frame.
  vtkPolyDataMapper2D* FrameMapper; //!< Mapper for \a Frame.
  vtkActor2D* FrameActor; //!< Actor for \a Frame.
  //@}

private:
  vtkScalarBarActor(const vtkScalarBarActor&) = delete;
  void operator=(const vtkScalarBarActor&) = delete;
};

#endif

