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

  Program:   Visualization Toolkit
  Module:    vtkPolygonalSurfacePointPlacer.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   vtkPolygonalSurfacePointPlacer
 * @brief   Place points on the surface of polygonal data.
 *
 *
 * vtkPolygonalSurfacePointPlacer places points on polygonal data and is
 * meant to be used in conjunction with
 * vtkPolygonalSurfaceContourLineInterpolator.
 *
 * @warning
 * You should have computed cell normals for the input polydata if you are
 * specifying a distance offset.
 *
 * @sa
 * vtkPointPlacer vtkPolyDataNormals
*/

#ifndef vtkPolygonalSurfacePointPlacer_h
#define vtkPolygonalSurfacePointPlacer_h

#include "vtkInteractionWidgetsModule.h" // For export macro
#include "vtkPolyDataPointPlacer.h"

class  vtkPolyDataCollection;
class  vtkCellPicker;
class  vtkPolygonalSurfacePointPlacerInternals;
class  vtkPolyData;

// The Node stores information about the point. This information is used by
// the interpolator. Reusing this information avoids the need for a second
// pick operation to regenerate it. (Cellpickers are slow).
struct vtkPolygonalSurfacePointPlacerNode
{
  double       WorldPosition[3];
  double       SurfaceWorldPosition[3];
  vtkIdType    CellId;
  vtkIdType    PointId;
  double       ParametricCoords[3]; // parametric coords within cell
  vtkPolyData  *PolyData;
};

class VTKINTERACTIONWIDGETS_EXPORT vtkPolygonalSurfacePointPlacer
                                  : public vtkPolyDataPointPlacer
{
public:
  /**
   * Instantiate this class.
   */
  static vtkPolygonalSurfacePointPlacer *New();

  //@{
  /**
   * Standard methods for instances of this class.
   */
  vtkTypeMacro(vtkPolygonalSurfacePointPlacer,vtkPolyDataPointPlacer);
  void PrintSelf(ostream& os, vtkIndent indent) override;
  //@}

  // Descuription:
  // Add /remove a prop, to place points on
  void AddProp( vtkProp * ) override;
  void RemoveViewProp(vtkProp *prop) override;
  void RemoveAllProps() override;

  /**
   * Given a renderer and a display position in pixel coordinates,
   * compute the world position and orientation where this point
   * will be placed. This method is typically used by the
   * representation to place the point initially.
   * For the Terrain point placer this computes world points that
   * lie at the specified height above the terrain.
   */
  int ComputeWorldPosition( vtkRenderer *ren,
                                    double displayPos[2],
                                    double worldPos[3],
                                    double worldOrient[9] ) override;

  /**
   * Given a renderer, a display position, and a reference world
   * position, compute the new world position and orientation
   * of this point. This method is typically used by the
   * representation to move the point.
   */
  int ComputeWorldPosition( vtkRenderer *ren,
                                    double displayPos[2],
                                    double refWorldPos[3],
                                    double worldPos[3],
                                    double worldOrient[9] ) override;

  /**
   * Given a world position check the validity of this
   * position according to the constraints of the placer
   */
  int ValidateWorldPosition( double worldPos[3] ) override;

  /**
   * Give the node a chance to update its auxiliary point id.
   */
  int UpdateNodeWorldPosition( double worldPos[3],
                                       vtkIdType nodePointId ) override;

  /**
   * Given a display position, check the validity of this position.
   */
  int ValidateDisplayPosition( vtkRenderer *, double displayPos[2] ) override;

  /**
   * Given a world position and a world orientation,
   * validate it according to the constraints of the placer.
   */
  int ValidateWorldPosition( double worldPos[3],
                                     double worldOrient[9] ) override;

  //@{
  /**
   * Get the Prop picker.
   */
  vtkGetObjectMacro( CellPicker, vtkCellPicker );
  //@}

  //@{
  /**
   * Be sure to add polydata on which you wish to place points to this list
   * or they will not be considered for placement.
   */
  vtkGetObjectMacro( Polys, vtkPolyDataCollection );
  //@}

  //@{
  /**
   * Height offset at which points may be placed on the polygonal surface.
   * If you specify a non-zero value here, be sure to compute cell normals
   * on your input polygonal data (easily done with vtkPolyDataNormals).
   */
  vtkSetMacro( DistanceOffset, double );
  vtkGetMacro( DistanceOffset, double );
  //@}

  //@{
  /**
   * Snap to the closest point on the surface ?
   * This is useful for the vtkPolygonalSurfaceContourLineInterpolator, when
   * drawing contours along the edges of a surface mesh.
   * OFF by default.
   */
  vtkSetMacro( SnapToClosestPoint, int );
  vtkGetMacro( SnapToClosestPoint, int );
  vtkBooleanMacro( SnapToClosestPoint, int );
  //@}

  //@{
  /**
   * Internally used by the interpolator.
   */
  typedef vtkPolygonalSurfacePointPlacerNode Node;
  Node *GetNodeAtWorldPosition( double worldPos[3] );
  //@}

protected:
  vtkPolygonalSurfacePointPlacer();
  ~vtkPolygonalSurfacePointPlacer() override;

  // The props that represents the terrain data (one or more) in a rendered
  // scene
  vtkCellPicker                           *CellPicker;
  vtkPolyDataCollection                   *Polys;
  vtkPolygonalSurfacePointPlacerInternals *Internals;
  double                                   DistanceOffset;
  int                                      SnapToClosestPoint;

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

#endif
