VTK  9.3.0
vtkPolygon.h
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1 // SPDX-FileCopyrightText: Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
2 // SPDX-License-Identifier: BSD-3-Clause
25 #ifndef vtkPolygon_h
26 #define vtkPolygon_h
27 
28 #include "vtkCell.h"
29 #include "vtkCommonDataModelModule.h" // For export macro
30 
31 VTK_ABI_NAMESPACE_BEGIN
32 class vtkDoubleArray;
33 class vtkIdTypeArray;
34 class vtkLine;
35 class vtkPoints;
36 class vtkQuad;
37 class vtkTriangle;
39 
40 class VTKCOMMONDATAMODEL_EXPORT vtkPolygon : public vtkCell
41 {
42 public:
43  static vtkPolygon* New();
44  vtkTypeMacro(vtkPolygon, vtkCell);
45  void PrintSelf(ostream& os, vtkIndent indent) override;
46 
48 
51  int GetCellType() override { return VTK_POLYGON; }
52  int GetCellDimension() override { return 2; }
53  int GetNumberOfEdges() override { return this->GetNumberOfPoints(); }
54  int GetNumberOfFaces() override { return 0; }
55  vtkCell* GetEdge(int edgeId) override;
56  vtkCell* GetFace(int) override { return nullptr; }
57  int CellBoundary(int subId, const double pcoords[3], vtkIdList* pts) override;
58  void Contour(double value, vtkDataArray* cellScalars, vtkIncrementalPointLocator* locator,
59  vtkCellArray* verts, vtkCellArray* lines, vtkCellArray* polys, vtkPointData* inPd,
60  vtkPointData* outPd, vtkCellData* inCd, vtkIdType cellId, vtkCellData* outCd) override;
61  void Clip(double value, vtkDataArray* cellScalars, vtkIncrementalPointLocator* locator,
62  vtkCellArray* tris, vtkPointData* inPd, vtkPointData* outPd, vtkCellData* inCd,
63  vtkIdType cellId, vtkCellData* outCd, int insideOut) override;
64  int EvaluatePosition(const double x[3], double closestPoint[3], int& subId, double pcoords[3],
65  double& dist2, double weights[]) override;
66  void EvaluateLocation(int& subId, const double pcoords[3], double x[3], double* weights) override;
67  int IntersectWithLine(const double p1[3], const double p2[3], double tol, double& t, double x[3],
68  double pcoords[3], int& subId) override;
69  int Triangulate(int index, vtkIdList* ptIds, vtkPoints* pts) override;
71  int subId, const double pcoords[3], const double* values, int dim, double* derivs) override;
72  int IsPrimaryCell() override { return 0; }
74 
81  double ComputeArea();
82 
92  void InterpolateFunctions(const double x[3], double* sf) override;
93 
95 
99  static void ComputeNormal(vtkPoints* p, int numPts, const vtkIdType* pts, double n[3]);
100  static void ComputeNormal(vtkPoints* p, double n[3]);
101  static void ComputeNormal(vtkIdTypeArray* ids, vtkPoints* pts, double n[3]);
103 
108  static void ComputeNormal(int numPts, double* pts, double n[3]);
109 
116  bool IsConvex();
117 
119 
123  static bool IsConvex(vtkPoints* p, int numPts, const vtkIdType* pts);
124  static bool IsConvex(vtkIdTypeArray* ids, vtkPoints* p);
125  static bool IsConvex(vtkPoints* p);
127 
129 
133  static bool ComputeCentroid(vtkPoints* p, int numPts, const vtkIdType* pts, double centroid[3]);
134  static bool ComputeCentroid(vtkIdTypeArray* ids, vtkPoints* pts, double centroid[3]);
136 
145  static double ComputeArea(vtkPoints* p, vtkIdType numPts, const vtkIdType* pts, double normal[3]);
146 
155  double p0[3], double p10[3], double& l10, double p20[3], double& l20, double n[3]);
156 
168  static int PointInPolygon(double x[3], int numPts, double* pts, double bounds[6], double n[3]);
169 
178  int Triangulate(vtkIdList* outTris);
179 
185 
193  int BoundedTriangulate(vtkIdList* outTris, double tol);
194 
200  static double DistanceToPolygon(
201  double x[3], int numPts, double* pts, double bounds[6], double closest[3]);
202 
211  static int IntersectPolygonWithPolygon(int npts, double* pts, double bounds[6], int npts2,
212  double* pts2, double bounds2[6], double tol, double x[3]);
213 
226  vtkCell* cell1, vtkCell* cell2, double tol, double p0[3], double p1[3]);
227 
229 
235  vtkGetMacro(UseMVCInterpolation, bool);
236  vtkSetMacro(UseMVCInterpolation, bool);
238 
240 
248  vtkSetClampMacro(Tolerance, double, 0.0, 1.0);
249  vtkGetMacro(Tolerance, double);
251 
252 protected:
254  ~vtkPolygon() override;
255 
256  // Compute the interpolation functions using Mean Value Coordinate.
257  void InterpolateFunctionsUsingMVC(const double x[3], double* weights);
258 
259  // variables used by instances of this class
260  double Tolerance; // Intersection tolerance set by public API
261  double Tol; // Internal tolerance set by ComputeBounds()
262  void ComputeTolerance(); // Compute the internal tolerance Tol
263 
264  int SuccessfulTriangulation; // Stops recursive triangulation if necessary
265  vtkIdList* Tris; // Output triangulation placed here
266 
267  // These are used for internal computation.
272 
273  // Parameter indicating whether to use Mean Value Coordinate algorithm
274  // for interpolation. The parameter is false by default.
276 
277  // Helper methods for triangulation------------------------------
278  // Made public for external access
279 public:
280  // Ear cut triangulation options. The order in which vertices are
281  // removed are controlled by different measures. Changing this can
282  // make subtle differences in some cases. Historically the
283  // PERIMETER2_TO_AREA_RATIO has been used.
285  {
286  PERIMETER2_TO_AREA_RATIO = 0,
287  DOT_PRODUCT = 1,
288  BEST_QUALITY = 2
289  };
290 
292 
300  int EarCutTriangulation(int measure = PERIMETER2_TO_AREA_RATIO);
301  int EarCutTriangulation(vtkIdList* outTris, int measure = PERIMETER2_TO_AREA_RATIO);
303 
305 
312  int UnbiasedEarCutTriangulation(int seed, int measure = PERIMETER2_TO_AREA_RATIO);
314  int seed, vtkIdList* outTris, int measure = PERIMETER2_TO_AREA_RATIO);
316 
317 private:
318  vtkPolygon(const vtkPolygon&) = delete;
319  void operator=(const vtkPolygon&) = delete;
320 };
321 
322 VTK_ABI_NAMESPACE_END
323 #endif
object to represent cell connectivity
Definition: vtkCellArray.h:185
represent and manipulate cell attribute data
Definition: vtkCellData.h:40
abstract class to specify cell behavior
Definition: vtkCell.h:59
vtkIdType GetNumberOfPoints() const
Return the number of points in the cell.
Definition: vtkCell.h:139
abstract superclass for arrays of numeric data
Definition: vtkDataArray.h:54
dynamic, self-adjusting array of double
list of point or cell ids
Definition: vtkIdList.h:32
dynamic, self-adjusting array of vtkIdType
Abstract class in support of both point location and point insertion.
a simple class to control print indentation
Definition: vtkIndent.h:38
cell represents a 1D line
Definition: vtkLine.h:32
represent and manipulate point attribute data
Definition: vtkPointData.h:39
represent and manipulate 3D points
Definition: vtkPoints.h:38
a cell that represents an n-sided polygon
Definition: vtkPolygon.h:41
int IsPrimaryCell() override
See the vtkCell API for descriptions of these methods.
Definition: vtkPolygon.h:72
static int PointInPolygon(double x[3], int numPts, double *pts, double bounds[6], double n[3])
Determine whether a point is inside the specified polygon.
double ComputeArea()
Compute the area of a polygon.
int GetCellType() override
See the vtkCell API for descriptions of these methods.
Definition: vtkPolygon.h:51
void Clip(double value, vtkDataArray *cellScalars, vtkIncrementalPointLocator *locator, vtkCellArray *tris, vtkPointData *inPd, vtkPointData *outPd, vtkCellData *inCd, vtkIdType cellId, vtkCellData *outCd, int insideOut) override
See the vtkCell API for descriptions of these methods.
vtkTriangle * Triangle
Definition: vtkPolygon.h:268
static bool IsConvex(vtkPoints *p, int numPts, const vtkIdType *pts)
Determine whether or not a polygon is convex.
int CellBoundary(int subId, const double pcoords[3], vtkIdList *pts) override
See the vtkCell API for descriptions of these methods.
vtkCell * GetFace(int) override
See the vtkCell API for descriptions of these methods.
Definition: vtkPolygon.h:56
static void ComputeNormal(int numPts, double *pts, double n[3])
Compute the polygon normal from an array of points.
int UnbiasedEarCutTriangulation(int seed, int measure=PERIMETER2_TO_AREA_RATIO)
A fast triangulation method.
static int IntersectPolygonWithPolygon(int npts, double *pts, double bounds[6], int npts2, double *pts2, double bounds2[6], double tol, double x[3])
Method intersects two polygons.
int GetNumberOfEdges() override
See the vtkCell API for descriptions of these methods.
Definition: vtkPolygon.h:53
static bool IsConvex(vtkPoints *p)
Determine whether or not a polygon is convex.
int Triangulate(int index, vtkIdList *ptIds, vtkPoints *pts) override
See the vtkCell API for descriptions of these methods.
void ComputeTolerance()
bool UseMVCInterpolation
Definition: vtkPolygon.h:275
static void ComputeNormal(vtkPoints *p, double n[3])
Computes the unit normal to the polygon.
double Tolerance
Definition: vtkPolygon.h:260
void InterpolateFunctionsUsingMVC(const double x[3], double *weights)
int GetNumberOfFaces() override
See the vtkCell API for descriptions of these methods.
Definition: vtkPolygon.h:54
static vtkPolygon * New()
int EvaluatePosition(const double x[3], double closestPoint[3], int &subId, double pcoords[3], double &dist2, double weights[]) override
See the vtkCell API for descriptions of these methods.
int Triangulate(vtkIdList *outTris)
Triangulate this polygon.
void PrintSelf(ostream &os, vtkIndent indent) override
Methods invoked by print to print information about the object including superclasses.
int NonDegenerateTriangulate(vtkIdList *outTris)
Same as Triangulate(vtkIdList *outTris) but with a first pass to split the polygon into non-degenerat...
int GetCellDimension() override
See the vtkCell API for descriptions of these methods.
Definition: vtkPolygon.h:52
static double DistanceToPolygon(double x[3], int numPts, double *pts, double bounds[6], double closest[3])
Compute the distance of a point to a polygon.
int SuccessfulTriangulation
Definition: vtkPolygon.h:264
void EvaluateLocation(int &subId, const double pcoords[3], double x[3], double *weights) override
See the vtkCell API for descriptions of these methods.
vtkQuad * Quad
Definition: vtkPolygon.h:269
void Derivatives(int subId, const double pcoords[3], const double *values, int dim, double *derivs) override
See the vtkCell API for descriptions of these methods.
vtkIdList * Tris
Definition: vtkPolygon.h:265
void Contour(double value, vtkDataArray *cellScalars, vtkIncrementalPointLocator *locator, vtkCellArray *verts, vtkCellArray *lines, vtkCellArray *polys, vtkPointData *inPd, vtkPointData *outPd, vtkCellData *inCd, vtkIdType cellId, vtkCellData *outCd) override
See the vtkCell API for descriptions of these methods.
~vtkPolygon() override
static bool IsConvex(vtkIdTypeArray *ids, vtkPoints *p)
Determine whether or not a polygon is convex.
int IntersectWithLine(const double p1[3], const double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId) override
See the vtkCell API for descriptions of these methods.
int ParameterizePolygon(double p0[3], double p10[3], double &l10, double p20[3], double &l20, double n[3])
Create a local s-t coordinate system for a polygon.
int EarCutTriangulation(vtkIdList *outTris, int measure=PERIMETER2_TO_AREA_RATIO)
A fast triangulation method.
vtkDoubleArray * TriScalars
Definition: vtkPolygon.h:270
static void ComputeNormal(vtkIdTypeArray *ids, vtkPoints *pts, double n[3])
Computes the unit normal to the polygon.
int BoundedTriangulate(vtkIdList *outTris, double tol)
Triangulate polygon and enforce that the ratio of the smallest triangle area to the polygon area is g...
int EarCutTriangulation(int measure=PERIMETER2_TO_AREA_RATIO)
A fast triangulation method.
vtkCell * GetEdge(int edgeId) override
See the vtkCell API for descriptions of these methods.
static bool ComputeCentroid(vtkPoints *p, int numPts, const vtkIdType *pts, double centroid[3])
Compute the centroid of a set of points.
static double ComputeArea(vtkPoints *p, vtkIdType numPts, const vtkIdType *pts, double normal[3])
Compute the area of a polygon in 3D.
void InterpolateFunctions(const double x[3], double *sf) override
Compute the interpolation functions/derivatives.
bool IsConvex()
Determine whether or not a polygon is convex.
vtkLine * Line
Definition: vtkPolygon.h:271
static bool ComputeCentroid(vtkIdTypeArray *ids, vtkPoints *pts, double centroid[3])
Compute the centroid of a set of points.
int UnbiasedEarCutTriangulation(int seed, vtkIdList *outTris, int measure=PERIMETER2_TO_AREA_RATIO)
A fast triangulation method.
double Tol
Definition: vtkPolygon.h:261
static void ComputeNormal(vtkPoints *p, int numPts, const vtkIdType *pts, double n[3])
Computes the unit normal to the polygon.
static int IntersectConvex2DCells(vtkCell *cell1, vtkCell *cell2, double tol, double p0[3], double p1[3])
Intersect two convex 2D polygons to produce a line segment as output.
a cell that represents a 2D quadrilateral
Definition: vtkQuad.h:37
a cell that represents a triangle
Definition: vtkTriangle.h:37
@ value
Definition: vtkX3D.h:220
@ index
Definition: vtkX3D.h:246
@ VTK_POLYGON
Definition: vtkCellType.h:53
int vtkIdType
Definition: vtkType.h:315