crystalspace.jbind.impl.csgeom.poly2d
Class csPoly2D

java.lang.Object
  crystalspace.jbind.impl.csNativeObject
      crystalspace.jbind.impl.csgeom.poly2d.csPoly2D

All Implemented Interfaces:

iPointer

public class csPoly2D

extends csNativeObject

The following class represents a general 2D polygon with a bounding box.

Author:

Java wrapper - Quentin Anciaux, c++ version - http://crystal.sourceforge.net/docs/online/pubapi/classcsPoly2D.php

Field Summary

Fields inherited from class crystalspace.jbind.impl.csNativeObject

ImplFactory, nPointer

Constructor Summary

csPoly2D()
Make a new empty polygon.

csPoly2D(csPoly2D copy)
Copy constructor.

csPoly2D(int start_size)
Make a new empty polygon.

csPoly2D(iPointer nPointer)

Method Summary

int	addVertex(csVector2 v) Add a vertex (2D) to the polygon.
int	addVertex(float x, float y) Add a vertex (2D) to the polygon.
boolean	clipAgainst(iClipper2D view) Clipping routines.
void	clipPlane(csPlane2 plane, csPoly2D right) This routine is similar to Intersect but it only returns the polygon on the 'right' (positive) side of the plane.
void	extendConvex(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.
csBox2	getBoundingBox() Get the bounding box (in 2D space) for this polygon.
csVector2	getFirst() Get the first vertex.
csVector2	getLast() Get the last vertex.
float	getSignedArea() Calculate the signed area of this polygon.
csVector2	getVertex(int i) Get the specified vertex.
int	getVertexCount() Get the number of vertices.
csVector2Array	getVertices() Get the array with all vertices.
boolean	in(csVector2 v) Test if this vector is inside the polygon.
static boolean	in(csVector2Array poly, csVector2 v) Test if a vector is inside the given polygon.
void	intersect(csPlane2 plane, csPoly2D left, csPoly2D right) Intersect this polygon with a given plane and return the two resulting polygons in left and right.
protected boolean	isNativePointerValidSafe(long nPointer)
csVector2	item(int i) Get the specified vertex.
void	makeEmpty() Initialize the polygon to empty.
void	makeRoom(int new_max) Make room for at least the specified number of vertices.
protected void	nDelete(long pointer)
void	random(int num, csBox2 max_bbox) Generate a random convex polygon with the specified number of vertices.
csPoly2D	set(csPoly2D other) Assignment operator.
void	setVertexCount(int n) Set the number of vertices.
void	setVertices(csVector2Array v) Set all polygon vertices at once.
void	updateBoundingBox() Update the bounding box (useful after SetVertices).

Methods inherited from class crystalspace.jbind.impl.csNativeObject

changePointer, equals, finalize, getPointer, getPointer, getPointerArray, hashCode, isMemoryOwner, isNativePointerValid, newNativeObject, setMemoryOwner, toString

Methods inherited from class java.lang.Object

clone, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

csPoly2D

public csPoly2D(iPointer nPointer)

Parameters:

nPointer -

csPoly2D

public csPoly2D()

Make a new empty polygon.

csPoly2D

public csPoly2D(int start_size)

Make a new empty polygon.

Parameters:

start_size -

csPoly2D

public csPoly2D(csPoly2D copy)

Copy constructor.

Parameters:

copy -

Method Detail

nDelete

protected void nDelete(long pointer)

Specified by:

nDelete in class csNativeObject

See Also:

csNativeObject.nDelete(long)

isNativePointerValidSafe

protected boolean isNativePointerValidSafe(long nPointer)

Specified by:

isNativePointerValidSafe in class csNativeObject

See Also:

crystalspace.jbind.impl.csNativeObject#isNativePointerValidSafe()

addVertex

public int addVertex(float x,
                     float y)

Add a vertex (2D) to the polygon. Return index of added vertex.

Parameters:

x -

y -

Returns:

addVertex

public int addVertex(csVector2 v)

Add a vertex (2D) to the polygon. Return index of added vertex. Definition at line 157 of file poly2d.h. References csVector2::x, and csVector2::y.

Parameters:

v -

Returns:

clipAgainst

public boolean 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.

Parameters:

view -

Returns:

clipPlane

public void clipPlane(csPlane2 plane,
                      csPoly2D right)

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

Parameters:

plane -

right -

extendConvex

public void extendConvex(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.

Parameters:

other -

this_edge -

getBoundingBox

public csBox2 getBoundingBox()

Get the bounding box (in 2D space) for this polygon. Definition at line 176 of file poly2d.h.

Returns:

getFirst

public csVector2 getFirst()

Get the first vertex. Definition at line 120 of file poly2d.h.

Returns:

getLast

public csVector2 getLast()

Get the last vertex. Definition at line 126 of file poly2d.h.

Returns:

getSignedArea

public float getSignedArea()

Calculate the signed area of this polygon.

Returns:

getVertex

public csVector2 getVertex(int i)

Get the specified vertex. Definition at line 93 of file poly2d.h.

Parameters:

i -

Returns:

getVertexCount

public int getVertexCount()

Get the number of vertices. Definition at line 78 of file poly2d.h.

Returns:

getVertices

public csVector2Array getVertices()

Get the array with all vertices. Definition at line 88 of file poly2d.h.

Returns:

in

public static boolean in(csVector2Array poly,
                         csVector2 v)

Test if a vector is inside the given polygon.

Parameters:

poly -

v -

Returns:

in

public boolean in(csVector2 v)

Test if this vector is inside the polygon.

Parameters:

v -

Returns:

intersect

public void intersect(csPlane2 plane,
                      csPoly2D left,
                      csPoly2D right)

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.

Parameters:

plane -

left -

right -

makeEmpty

public void makeEmpty()

Initialize the polygon to empty.

makeRoom

public void makeRoom(int new_max)

Make room for at least the specified number of vertices. Referenced by SetVertexCount(), and SetVertices().

Parameters:

new_max -

set

public csPoly2D set(csPoly2D other)

Assignment operator.

Parameters:

other -

Returns:

item

public csVector2 item(int i)

Get the specified vertex. Definition at line 111 of file poly2d.h.

Parameters:

i -

Returns:

random

public void random(int num,
                   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.

Parameters:

num -

max_bbox -

setVertexCount

public void setVertexCount(int n)

Set the number of vertices. Definition at line 147 of file poly2d.h. References MakeRoom().

Parameters:

n -

setVertices

public void setVertices(csVector2Array v)

Set all polygon vertices at once. Copies the array. Note! This doesn't update the bounding box! Definition at line 169 of file poly2d.h. References MakeRoom().

Parameters:

v -

updateBoundingBox

public void updateBoundingBox()

Update the bounding box (useful after SetVertices).