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TPolygon2

[TPolygon2](API\Runtime\GeometryCore\TPolygon2) is a 2D polygon represented as a list of Vertices.

API > API/Runtime > API/Runtime/GeometryCore

TPolygon2 is a 2D polygon represented as a list of Vertices.

   
Name TPolygon2
Type class
Header File /Engine/Source/Runtime/GeometryCore/Public/Polygon2.h
Include Path #include "Polygon2.h"
Source /Engine/Source/Runtime/GeometryCore/Public/CompGeom/Delaunay2.h

Syntax

template<typename T>  
class TPolygon2

Constructors

Name Remarks Include Path Unreal Specifiers

TPolygon2 ( const TArray< TVector2< T > >& VertexList
)

 Construct polygon with given list of vertices Polygon2.h  
  Polygon2.h  

TPolygon2 ( const TArray< OtherVertexType >& VertexList
)

   Polygon2.h  

TPolygon2 ( TArrayView< const TVector2< T > > VertexArray,
TArrayView< const int32 > VertexIndices
)

 Construct polygon with given indices into a vertex array Polygon2.h  

Classes

Name Remarks
SegmentEnumerable Wrapper around SegmentIterator that has begin() and end() suitable for range-based for loop
SegmentIterator SegmentIterator is used to iterate over the TSegment2 segments of the polygon

Functions

Public

Name Remarks Include Path Unreal Specifiers

void AppendVertex ( const TVector2< T >& Position
)

 Add a vertex to the Polygon Polygon2.h  

void AppendVertices ( const TArray< TVector2< T > >& NewVertices
)

 Add a list of Vertices to the Polygon Polygon2.h  

T Area()

   Polygon2.h  

T AverageEdgeLength()

   Polygon2.h  

TAxisAlignedBox2< T > Bounds()

   Polygon2.h  

void Chamfer ( T ChamferDist,
T MinConvexAngleDeg,
T MinConcaveAngleDeg
)

 Chamfer each vertex corner of the Polygon Polygon2.h  

void ClipConvex ( const TAxisAlignedBox2< T >& Bounds
)

 Clip polygon to the given bounds. Polygon2.h  

bool Contains ( const TSegment2< T >& Segment
) const

   Polygon2.h  

bool Contains ( const TPolygon2< T >& OtherPoly
) const

   Polygon2.h  

bool Contains ( const TVector2< T >& QueryPoint
) const

   Polygon2.h  

T DistanceSquared ( const TVector2< T >& QueryPoint,
int& NearestSegIndexOut,
T& NearestSegParamOut
) const

 Calculate the squared distance from a point to the polygon Polygon2.h  

T DistanceSquared ( const TVector2< T >& QueryPoint
) const

 Calculate the squared distance from a point to the polygon Polygon2.h  

bool FindIntersections ( const TPolygon2< T >& OtherPoly,
TArray< TVector2< T > >& OutArray
) const

 Find all the points where an edge of the Polygon intersects an edge of the OtherPolygon Polygon2.h  

TVector2< T > GetNormal ( int iSeg,
T SegmentParam
) const

   Polygon2.h  

TVector2< T > GetNormal ( int VertexIndex
) const

 Get the normal vector at a vertex of the polygon, which is perpendicular to GetTangent() Points "inward" for a Clockwise Polygon, and outward for CounterClockwise Polygon2.h  

TVector2< T > GetNormal_FaceAvg ( int VertexIndex
) const

 Construct a normal at a vertex of the Polygon by averaging the adjacent face normals. Polygon2.h  

TVector2< T > GetSegmentPoint ( int SegmentIndex,
T SegmentParam
) const

   Polygon2.h  

TVector2< T > GetSegmentPointUnitParam ( int SegmentIndex,
T SegmentParam
) const

   Polygon2.h  

TVector2< T > GetTangent ( int VertexIndex
) const

 Get the tangent vector at a vertex of the polygon, which is the normalized vector from the previous vertex to the next vertex Polygon2.h  

const TArray< TVector2< T > > & GetVertices()

   Polygon2.h  

bool Intersects ( const TPolygon2< T >& OtherPoly
) const

   Polygon2.h  

bool Intersects ( const TSegment2< T >& Segment
) const

   Polygon2.h  

bool IsClockwise()

   Polygon2.h  

bool IsConvex ( T RadiansTolerance,
bool bDegenerateIsConvex
) const

   Polygon2.h  

void NeighbourPoints ( int VertexIdx,
TVector2< T >& OutPrevNbr,
TVector2< T >& OutNextNbr
) const

 Get the previous and next vertex positions for a given vertex of the Polygon Polygon2.h  

void NeighbourVectors ( int VertexIdx,
TVector2< T >& OutToPrev,
TVector2< T >& OutToNext,
bool bNormalize
) const

 Get the vectors from a given vertex to the previous and next Vertices, optionally normalized Polygon2.h  

T OpeningAngleDeg ( int iVertex
) const

   Polygon2.h  

bool Overlaps ( const TPolygon2< T >& OtherPoly
) const

 Check for polygon overlap, aka solid intersection. Polygon2.h  

T Perimeter()

   Polygon2.h  

void PolyOffset ( T OffsetDistance
)

 Offset polygon by fixed distance, by offsetting and intersecting edges. Polygon2.h  

void RemoveVertex ( int VertexIndex
)

 Remove a vertex of the Polygon (existing Vertices are shifted) Polygon2.h  

void Reverse()

 Reverse the order of the Vertices in the Polygon (ie switch between Clockwise and CounterClockwise) Polygon2.h  

TPolygon2< T > & Scale ( const TVector2< T >& Scale,
const TVector2< T >& Origin
)

 Scale the Polygon relative to a given point Polygon2.h  

TSegment2< T > Segment ( int SegmentIndex
) const

   Polygon2.h  

SegmentIterator SegmentItr()

   Polygon2.h  

SegmentEnumerable Segments()

   Polygon2.h  

void Set ( int VertexIndex,
const TVector2< T >& Position
)

 Set vertex at given index to a new Position Polygon2.h  

void SetVertices ( const TArray< TVector2< T > >& NewVertices
)

 Replace the list of Vertices with a new list Polygon2.h  

T SignedArea()

   Polygon2.h  

void Simplify ( T ClusterTolerance,
T LineDeviationTolerance
)

 Simplify the Polygon to reduce the vertex count Polygon2.h  

const TVector2< T > & Start()

   Polygon2.h  

TPolygon2< T > & Transform ( const TFunction< TVector2< T >(const TVector2< T >&)>& TransformFunc
)

 Apply an arbitrary transformation to the Polygon Polygon2.h  

TPolygon2< T > & Translate ( const TVector2< T >& Translate
)

 Translate the polygon Polygon2.h  

int VertexCount()

   Polygon2.h  

void VtxNormalOffset ( T OffsetDistance,
bool bUseFaceAvg
)

 Offset each point by the given Distance along vertex "normal" direction Polygon2.h  

T WindingIntegral ( const TVector2< T >& QueryPoint
) const

   Polygon2.h  

Static

Name Remarks Include Path Unreal Specifiers

static TPolygon2< T > MakeCircle ( T Radius,
int Steps,
T AngleShiftRadians
)

 Construct a circular polygon Polygon2.h  

static TPolygon2< T > MakeRectangle ( const TVector2< T >& Center,
T Width,
T Height
)

 Construct a four-vertex rectangle polygon Polygon2.h  

static TPolygon2< T > MakeRoundedRectangle ( const TVector2< T >& Center,
T Width,
T Height,
T Corner,
int CornerSteps
)

 Construct a rounded rectangle polygon Polygon2.h  

static void SimplifyDouglasPeucker ( T Tolerance,
const TArray< TVector2< T > >& Vertices,
int j,
int k,
TArray< bool >& Marked
)

 Polygon simplification code adapted from: http://softsurfer.com/Archive/algorithm_0205/algorithm_0205.htm simplifyDP(): This is the Douglas-Peucker recursive simplification routine It just marks Vertices that are part of the simplified polyline for approximating the polyline subchain v[j] to v[k]. Polygon2.h  

Operators

Name Remarks Include Path Unreal Specifiers

const TVector2< T > & operator[] ( int Index
) const

 Get the vertex at a given index Polygon2.h  

TVector2< T > & operator[] ( int Index
)

 Get the vertex at a given index Polygon2.h  

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