jvx.geom
Class PgPolygonOnElementSet

java.lang.Object
  |
  +--jv.object.PsObject
        |
        +--jvx.geom.PgPolygonOnElementSet

All Implemented Interfaces:

java.lang.Cloneable, PsUpdateIf, java.io.Serializable

public class PgPolygonOnElementSet

extends PsObject

A polygon that lives on an element set. Every point of a PolygonOnElementSet is given by the element index of the element the point lies on, and the barycentric coordinates in respect to this triangle. Only for triangulations.

Version:

28.09.00, 1.40 revised (ep) Changed handling of null-parameter in constructor.
28.08.00, 1.30 revised (ep) Added setAccuracy(double) and corresponding variable m_eps. Changed method exp(...) to match that.
28.08.00, 1.20 revised (ep) Added getGeometry().
21.11.99, 1.01 removed static methods to class PwBary (ep)
30.06.99, 1.00 created (ep)

Author:

Eike Preuß

See Also:

PgPolygon, PgElementSet, Serialized Form

Field Summary

static double	BARYEPS Accuracy used at checks for zero in barycentric coordinates as default (used e.g. in exp(...)).
protected PiVector	m_elem Global element indices as in underlying element set.
double	m_eps This accuracy is actually used for zero-checks in barycentric coordinates (used e.g. in exp(...)).
protected PgElementSet	m_geom Underlying element set.
protected int	m_maxNum Maximum number of vertices, internal use only.
protected PdBary[]	m_pos Barycentric coordinates of the points.
protected int	m_size Number of vertices, do not set directly, use setNumVertices().

Fields inherited from class jv.object.PsObject

HAS_CONFIG_PANEL, HAS_INFO_PANEL, HAS_MATERIAL_PANEL, INSPECTOR_INFO, INSPECTOR_INFO_EXT, IS_DELETED, IS_FIXED, IS_SELECTED, IS_USED, m_infoPanel, m_name, m_panelList, m_parent, m_tag, m_updateList, NUM_TAGS

Constructor Summary

PgPolygonOnElementSet(PgElementSet geom)
Constructs a new polygon on an element set.

Method Summary

void	addPolygon(PgPolygonOnElementSet poly) Concatenates two polygons on element sets, ignoring the underlying geometries.
double	eval(PdVector bary1, PdVector bary2, PdVector bary3, PiVector outelem, double step) Evaluates the polygon in given steps and returns the calculated points in order.
PdBaryDir	exp(int iniElem, PdBary iniBary, PdBaryDir iniDir, double length) Makes discret exponential map, i.e. the straightest geodesic from given initial values.
PdBaryDir	exp(int iniElem, PdBary iniBary, PdBaryDir iniDir, double length, PgPolygon outpoly) Makes discret exponential map, i.e. the straightest geodesic from given initial values.
PdBary[]	getBary() Returns a reference to the barycentric coordinates.
PdBary	getBary(int index) Returns barycentric coordinates of the vertex at given index
PiVector	getElemInd() Returns a reference to the global element indices.
int	getElemInd(int index) Returns global element index of the element the vertex at given index lies on
PgElementSet	getGeometry()
double	getLength() Shortcut to getPolygon().getLength().
int	getNumVertices() Returns the number of points of the polygon.
PgPolygon	getPolygon() Returns polygon in world coordinates.
boolean	getPolygon(PgPolygon out)
void	setAccuracy(double newacc) Sets the accuracy that is used at checks for zero in barycentric coordinates.
void	setGeometry(PgElementSet geom) Changes the underlying geometry.
protected void	setMaxNumVertices(int max) Method should not be called directly, only subclass.setMaxNumVertices may call it.
void	setNumVertices(int num) Existing vertices keep their values (if their position is less than num).
void	setVertex(int index, int elem, PdBary bary) Sets vertex at given index to be on given element with given barycentric coordinates.
java.lang.String	toString() a long long description

Methods inherited from class jv.object.PsObject

addInspector, addUpdateListener, clearTag, clone, clone, clone, copy, getFather, getInfoPanel, getInspector, getName, getNumObjects, hasInspector, hasTag, hasUpdateListener, init, instanceOf, instanceOf, removeInspector, removeUpdateListener, setName, setParent, setTag, update, updatePanels

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

BARYEPS

public static double BARYEPS

Accuracy used at checks for zero in barycentric coordinates as default (used e.g. in exp(...)).

m_eps

public double m_eps

This accuracy is actually used for zero-checks in barycentric coordinates (used e.g. in exp(...)).

m_geom

protected PgElementSet m_geom

Underlying element set.

m_maxNum

protected int m_maxNum

Maximum number of vertices, internal use only.

m_size

protected int m_size

Number of vertices, do not set directly, use setNumVertices().

m_elem

protected PiVector m_elem

Global element indices as in underlying element set.

m_pos

protected PdBary[] m_pos

Barycentric coordinates of the points.

Constructor Detail

PgPolygonOnElementSet

public PgPolygonOnElementSet(PgElementSet geom)

Constructs a new polygon on an element set. If geometry is null, then the method setGeometry has to be called before it is useful to use the instance of this class.

Parameters:

geom - Underlying element set. Must be a triangulation. It is possible to triangulate an element set by the method PgElementSet.triangulate(...).

See Also:

PgElementSet.triangulate(jv.geom.PgElementSet)

Method Detail

setGeometry

public void setGeometry(PgElementSet geom)

Changes the underlying geometry.

Parameters:

geom - new underlying triangulation

getGeometry

public PgElementSet getGeometry()

Returns:

reference to underlying triangulation

setMaxNumVertices

protected void setMaxNumVertices(int max)

Method should not be called directly, only subclass.setMaxNumVertices may call it. The user should change the number of vertices via setNumVertices().

See Also:

#setNumVertices()

setNumVertices

public void setNumVertices(int num)

Existing vertices keep their values (if their position is less than num). Necessary memory is allocated.

setVertex

public void setVertex(int index,
                      int elem,
                      PdBary bary)

Sets vertex at given index to be on given element with given barycentric coordinates.

Parameters:

index - vertex index in vertex arrays

elem - global element index where the vertex shall lie on

bary - barycentric coordinates of vertex in element

getBary

public PdBary[] getBary()

Returns a reference to the barycentric coordinates.

getElemInd

public PiVector getElemInd()

Returns a reference to the global element indices.

getNumVertices

public int getNumVertices()

Returns the number of points of the polygon.

getBary

public PdBary getBary(int index)

Returns barycentric coordinates of the vertex at given index

getElemInd

public int getElemInd(int index)

Returns global element index of the element the vertex at given index lies on

eval

public double eval(PdVector bary1,
                   PdVector bary2,
                   PdVector bary3,
                   PiVector outelem,
                   double step)

Evaluates the polygon in given steps and returns the calculated points in order.

Parameters:

bary1 - output: contains the first barycentric coordinate of all evaluated points

bary1 - output: contains the second barycentric coordinate of all evaluated points

bary1 - output: contains the third barycentric coordinate of all evaluated points

outelem - output: element indices of all evaluated points

step - stepsize in world metrics

Returns:

distance of last step (that is less than step)

getPolygon

public PgPolygon getPolygon()

Returns polygon in world coordinates.

getPolygon

public boolean getPolygon(PgPolygon out)

Parameters:

out - output: here the polygon is put

Returns:

true at success

getLength

public double getLength()

Shortcut to getPolygon().getLength().

Returns:

length of polygon in world metrics

addPolygon

public void addPolygon(PgPolygonOnElementSet poly)

Concatenates two polygons on element sets, ignoring the underlying geometries.

Parameters:

poly - vertices of poly are added to the polygon

toString

public java.lang.String toString()

a long long description

Overrides:

toString in class PsObject

exp

public PdBaryDir exp(int iniElem,
                     PdBary iniBary,
                     PdBaryDir iniDir,
                     double length)

Makes discret exponential map, i.e. the straightest geodesic from given initial values.

Parameters:

geom - ElementSet on which the geodesic lives. must be a triangulation.

iniElem - index of starting point's element

iniBary - the barycentric coordinates of the initial point

iniDir - the initial direction in barycentric notation

length - the euclidian length of the geodesic is length*norm(iniDir)

Returns:

null at an error; else the last barycentric direction that was used

exp

public PdBaryDir exp(int iniElem,
                     PdBary iniBary,
                     PdBaryDir iniDir,
                     double length,
                     PgPolygon outpoly)

Makes discret exponential map, i.e. the straightest geodesic from given initial values.

Parameters:

geom - ElementSet on which the geodesic lives. Must be a triangulation.

iniElem - index of starting point's element

iniBary - barycentric coordinates of the initial point

iniDir - initial direction in barycentric notation

length - euclidian length of the geodesic is length*norm(iniDir)

outpoly - if outpoly is not null the method puts the whole geodesic here

Returns:

null at an error; else the last barycentric direction that was used

setAccuracy

public void setAccuracy(double newacc)

Sets the accuracy that is used at checks for zero in barycentric coordinates. Default is defined in static field BARYEPS.