Tools/Win64/VTK/include/vtk-9.0/vtkExtractSelectedFrustum.h

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

  Program:   Visualization Toolkit
  Module:    vtkExtractSelectedFrustum.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   vtkExtractSelectedFrustum
 * @brief   Returns the portion of the input dataset that
 * lies within a selection frustum.
 *
 *
 * This class intersects the input DataSet with a frustum and determines which
 * cells and points lie within the frustum. The frustum is defined with a
 * vtkPlanes containing six cutting planes. The output is a DataSet that is
 * either a shallow copy of the input dataset with two new "vtkInsidedness"
 * attribute arrays, or a completely new UnstructuredGrid that contains only
 * the cells and points of the input that are inside the frustum. The
 * PreserveTopology flag controls which occurs. When PreserveTopology is off
 * this filter adds a scalar array called vtkOriginalCellIds that says what
 * input cell produced each output cell. This is an example of a Pedigree ID
 * which helps to trace back results.
 *
 * @sa
 * vtkExtractGeometry, vtkAreaPicker, vtkExtractSelection, vtkSelection
 */

#ifndef vtkExtractSelectedFrustum_h
#define vtkExtractSelectedFrustum_h

#include "vtkExtractSelectionBase.h"
#include "vtkFiltersGeneralModule.h" // For export macro

class vtkPlanes;
class vtkInformation;
class vtkInformationVector;
class vtkCell;
class vtkPoints;
class vtkDoubleArray;

class VTKFILTERSGENERAL_EXPORT vtkExtractSelectedFrustum : public vtkExtractSelectionBase
{
public:
  static vtkExtractSelectedFrustum* New();
  vtkTypeMacro(vtkExtractSelectedFrustum, vtkExtractSelectionBase);
  void PrintSelf(ostream& os, vtkIndent indent) override;

  /**
   * Return the MTime taking into account changes to the Frustum
   */
  vtkMTimeType GetMTime() override;

  //@{
  /**
   * Set the selection frustum. The planes object must contain six planes.
   */
  virtual void SetFrustum(vtkPlanes*);
  vtkGetObjectMacro(Frustum, vtkPlanes);
  //@}

  /**
   * Given eight vertices, creates a frustum.
   * each pt is x,y,z,1
   * in the following order
   * near lower left, far lower left
   * near upper left, far upper left
   * near lower right, far lower right
   * near upper right, far upper right
   */
  void CreateFrustum(double vertices[32]);

  //@{
  /**
   * Return eight points that define the selection frustum. Valid if
   * create Frustum was used, invalid if SetFrustum was.
   */
  vtkGetObjectMacro(ClipPoints, vtkPoints);
  //@}

  //@{
  /**
   * Sets/gets the intersection test type.
   */
  vtkSetMacro(FieldType, int);
  vtkGetMacro(FieldType, int);
  //@}

  //@{
  /**
   * Sets/gets the intersection test type. Only meaningful when fieldType is
   * vtkSelection::POINT
   */
  vtkSetMacro(ContainingCells, int);
  vtkGetMacro(ContainingCells, int);
  //@}

  /**
   * Does a quick test on the AABBox defined by the bounds.
   */
  int OverallBoundsTest(double* bounds);

  //@{
  /**
   * When On, this returns an unstructured grid that outlines selection area.
   * Off is the default.
   */
  vtkSetMacro(ShowBounds, vtkTypeBool);
  vtkGetMacro(ShowBounds, vtkTypeBool);
  vtkBooleanMacro(ShowBounds, vtkTypeBool);
  //@}

  //@{
  /**
   * When on, extracts cells outside the frustum instead of inside.
   */
  vtkSetMacro(InsideOut, vtkTypeBool);
  vtkGetMacro(InsideOut, vtkTypeBool);
  vtkBooleanMacro(InsideOut, vtkTypeBool);
  //@}

protected:
  vtkExtractSelectedFrustum(vtkPlanes* f = nullptr);
  ~vtkExtractSelectedFrustum() override;

  // sets up output dataset
  int RequestDataObject(vtkInformation* request, vtkInformationVector** inputVector,
    vtkInformationVector* outputVector) override;

  // execution
  int RequestData(vtkInformation*, vtkInformationVector**, vtkInformationVector*) override;
  int ABoxFrustumIsect(double bounds[], vtkCell* cell);
  int FrustumClipPolygon(int nverts, double* ivlist, double* wvlist, double* ovlist);
  void PlaneClipPolygon(int nverts, double* ivlist, int pid, int& noverts, double* ovlist);
  void PlaneClipEdge(double* V0, double* V1, int pid, int& noverts, double* overts);
  int IsectDegenerateCell(vtkCell* cell);

  // used in CreateFrustum
  void ComputePlane(
    int idx, double v0[3], double v1[2], double v2[3], vtkPoints* points, vtkDoubleArray* norms);

  // modes
  int FieldType;
  int ContainingCells;
  vtkTypeBool InsideOut;

  // used internally
  vtkPlanes* Frustum;
  int np_vertids[6][2];

  // for debugging
  vtkPoints* ClipPoints;
  int NumRejects;
  int NumIsects;
  int NumAccepts;
  vtkTypeBool ShowBounds;

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

#endif