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csPoly2D Class Reference
[Geometry utilities]

The following class represents a general 2D polygon. More...

#include <csgeom/poly2d.h>

List of all members.

Public Member Functions

 csPoly2D (int start_size=10)
 Make a new empty polygon.
 csPoly2D (const csPoly2D &copy)
 Copy constructor.
 ~csPoly2D ()
 Destructor.
csPoly2Doperator= (const csPoly2D &other)
 Assignment operator.
void MakeEmpty ()
 Initialize the polygon to empty.
int GetVertexCount () const
 Get the number of vertices.
csVector2GetVertices ()
 Get the array with all vertices.
const csVector2GetVertices () const
 Get the array with all vertices.
csVector2GetVertex (int i)
 Get the specified vertex.
csVector2operator[] (int i)
 Get the specified vertex.
const csVector2operator[] (int i) const
 Get the specified vertex.
csVector2GetFirst ()
 Get the first vertex.
csVector2GetLast ()
 Get the last vertex.
bool In (const csVector2 &v)
 Test if this vector is inside the polygon.
void MakeRoom (int new_max)
 Make room for at least the specified number of vertices.
void SetVertexCount (int n)
 Set the number of vertices.
int AddVertex (const csVector2 &v)
 Add a vertex (2D) to the polygon.
int AddVertex (float x, float y)
 Add a vertex (2D) to the polygon.
void SetVertices (csVector2 const *v, int num)
 Set all polygon vertices at once.
bool ClipAgainst (iClipper2D *view)
 Clipping routines.
void Intersect (const csPlane2 &plane, csPoly2D &left, csPoly2D &right) const
 Intersect this polygon with a given plane and return the two resulting polygons in left and right.
void ClipPlane (const csPlane2 &plane, csPoly2D &right) const
 This routine is similar to Intersect but it only returns the polygon on the 'right' (positive) side of the plane.
void ExtendConvex (const csPoly2D &other, int this_edge)
 Extend this polygon with another polygon so that the resulting polygon is: (a) still convex, (b) fully contains this polygon, and (c) contains as much as possible of the other polgon.
float GetSignedArea ()
 Calculate the signed area of this polygon.
void Random (int num, const csBox2 &max_bbox)
 Generate a random convex polygon with the specified number of vertices.

Static Public Member Functions

bool In (csVector2 *poly, int num_poly, const csVector2 &v)
 Test if a vector is inside the given polygon.

Protected Attributes

csVector2vertices
 The 2D vertices.


Detailed Description

The following class represents a general 2D polygon.

Definition at line 38 of file poly2d.h.


Constructor & Destructor Documentation

csPoly2D::csPoly2D int  start_size = 10  ) 
 

Make a new empty polygon.

csPoly2D::csPoly2D const csPoly2D copy  ) 
 

Copy constructor.

csPoly2D::~csPoly2D  ) 
 

Destructor.


Member Function Documentation

int csPoly2D::AddVertex float  x,
float  y
 

Add a vertex (2D) to the polygon.

Return index of added vertex.

int csPoly2D::AddVertex const csVector2 v  )  [inline]
 

Add a vertex (2D) to the polygon.

Return index of added vertex.

Definition at line 149 of file poly2d.h.

References csVector2::x, and csVector2::y.

bool csPoly2D::ClipAgainst iClipper2D view  ) 
 

Clipping routines.

They return false if the resulting polygon is not visible for some reason. Note that these routines must not be called if the polygon is not visible. These routines will not check that. Note that these routines will put the resulting clipped 2D polygon in place of the original 2D polygon.

void csPoly2D::ClipPlane const csPlane2 plane,
csPoly2D right
const
 

This routine is similar to Intersect but it only returns the polygon on the 'right' (positive) side of the plane.

void csPoly2D::ExtendConvex const csPoly2D other,
int  this_edge
 

Extend this polygon with another polygon so that the resulting polygon is: (a) still convex, (b) fully contains this polygon, and (c) contains as much as possible of the other polgon.

'this_edge' is the index of the common edge for this polygon. Edges are indexed with 0 being the edge from 0 to 1 and n-1 being the edge from n-1 to 0.

csVector2* csPoly2D::GetFirst  )  [inline]
 

Get the first vertex.

Definition at line 112 of file poly2d.h.

csVector2* csPoly2D::GetLast  )  [inline]
 

Get the last vertex.

Definition at line 118 of file poly2d.h.

References vertices.

float csPoly2D::GetSignedArea  ) 
 

Calculate the signed area of this polygon.

csVector2* csPoly2D::GetVertex int  i  )  [inline]
 

Get the specified vertex.

Definition at line 85 of file poly2d.h.

References vertices.

int csPoly2D::GetVertexCount  )  const [inline]
 

Get the number of vertices.

Definition at line 70 of file poly2d.h.

const csVector2* csPoly2D::GetVertices  )  const [inline]
 

Get the array with all vertices.

Definition at line 80 of file poly2d.h.

csVector2* csPoly2D::GetVertices  )  [inline]
 

Get the array with all vertices.

Definition at line 75 of file poly2d.h.

bool csPoly2D::In csVector2 poly,
int  num_poly,
const csVector2 v
[static]
 

Test if a vector is inside the given polygon.

bool csPoly2D::In const csVector2 v  ) 
 

Test if this vector is inside the polygon.

void csPoly2D::Intersect const csPlane2 plane,
csPoly2D left,
csPoly2D right
const
 

Intersect this polygon with a given plane and return the two resulting polygons in left and right.

This version is robust. If one of the edges of this polygon happens to be on the same plane as 'plane' then the edge will go to the polygon which already has most edges. i.e. you will not get degenerate polygons.

void csPoly2D::MakeEmpty  ) 
 

Initialize the polygon to empty.

void csPoly2D::MakeRoom int  new_max  ) 
 

Make room for at least the specified number of vertices.

Referenced by SetVertexCount(), and SetVertices().

csPoly2D& csPoly2D::operator= const csPoly2D other  ) 
 

Assignment operator.

const csVector2& csPoly2D::operator[] int  i  )  const [inline]
 

Get the specified vertex.

Definition at line 103 of file poly2d.h.

References vertices.

csVector2& csPoly2D::operator[] int  i  )  [inline]
 

Get the specified vertex.

Definition at line 94 of file poly2d.h.

References vertices.

void csPoly2D::Random int  num,
const csBox2 max_bbox
 

Generate a random convex polygon with the specified number of vertices.

The polygon will be inside the given bounding box. @@ Currently only triangles are supported.

void csPoly2D::SetVertexCount int  n  )  [inline]
 

Set the number of vertices.

Definition at line 139 of file poly2d.h.

References MakeRoom().

void csPoly2D::SetVertices csVector2 const *  v,
int  num
[inline]
 

Set all polygon vertices at once.

Copies the array. Note! This doesn't update the bounding box!

Definition at line 161 of file poly2d.h.

References MakeRoom(), and vertices.


Member Data Documentation

csVector2* csPoly2D::vertices [protected]
 

The 2D vertices.

Definition at line 42 of file poly2d.h.

Referenced by GetLast(), GetVertex(), operator[](), and SetVertices().


The documentation for this class was generated from the following file:
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