jv.geom

Class PgVectorField

java.lang.Object

jv.object.PsObject

jv.project.PgGeometry

jv.geom.PgVectorField

All Implemented Interfaces:

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

public class PgVectorField
extends PgGeometry

Vector field along a point set, polygon or surface. Each vector has a vertex or element center of the associated geometry as base point. The base points must be implicitly reconstructed from the associated geometry and the flag 'basedOn'.

Note, usually the vector field should also be registered in the geometry.

Usage example:

   ...
   PgElementSet surf = new PgElementSet(...
   ...
   PgVectorField field = new PgVectorField(3);
   field.setType(PgVectorField.ELEMENT_BASED);  // base points are element midpoints of surface
   field.setGeometry(surf);                                                             // register geometry to use base points from geometry
   
   surf.addVectorField(field);                                          // assign vector field to surface, otherwise vector field is not visible
   ...
 

See Also:

PgPointSet, PgElementSet, Serialized Form

Author:

Konrad Polthier

Version:

04.10.19, 2.81 revised (jr) Bug fix: in PgVectorField.project parallelity check.
07.07.13, 2.80 revised (kp) Unused methods computeGradient() removed where function was given as PgPointSet.
29.08.09, 2.72 revised (fk) implemented add(PgVectorField).
29.08.09, 2.71 revised (fk) changed method signature from PgVF.sub(v1, v2) to v1.sub(v2).
29.02.04, 2.70 revised (kp) Dimension of vectors better separated from m_dim, method blend() and clone() improved.
10.02.03, 2.60 revised (ep) MakeTangent for 2-dim surfaces in arbitrary dimensional ambient space and for vertex and element based. JavaDoc.
23.01.03, 2.50 revised (kp) Individual material properties activated.
24.06.02, 2.10 revised (ep) getInterpolatedElementSet moved to PwVectorField. New method getGeometry.
09.06.02, 2.00 revised (ep) New methods setDimOfVectors() and getInterpolatedElementBased().
22.03.02, 1.90 revised (ur) Internationalization.
13.09.01, 1.80 revised (ep) setVectors now behaves like documented.
20.05.01, 1.70 revised (kp) Minor revisions in a few methods.
19.05.01, 1.60 revised (kp) Vector field handling slightly revised.
10.12.00, 1.50 revised (ep) Method getDimOfVectors() added.
18.07.00, 1.40 revised (kp) Instance variable m_useGlobalVectorColor renamed to m_bShowVectorColors.
26.06.00, 1.30 revised (ep) Copy() method added.
09.04.00, 1.20 revised (kp) Name changed to PgVectorField_IP from PgVectorField_IP.
20.11.99, 1.10 revised (ep) Removed reference to vertices.
00.00.98, 1.00 created (kp)

Field Summary

Fields

Modifier and Type	Field and Description
static int	ELEMENT_BASED VectorField is given at element centers.
static int	VERTEX_BASED VectorField is given at vertices.

Fields inherited from class jv.object.PsObject

HAS_BOUNDARY_PANEL, HAS_CONFIG_PANEL, HAS_INFO_PANEL, HAS_LABEL_PANEL, HAS_MATERIAL_PANEL, HAS_TEXTURE_PANEL, HAS_VECTOR_PANEL, INSPECTOR_INFO, INSPECTOR_INFO_EXT, IS_DELETED, IS_FIXED, IS_FOCUSSED, IS_PICKED, IS_SELECTED, IS_USED, NUM_TAGS

Fields inherited from interface jv.project.PgGeometryIf

AMBIENT_H2_HYPERBOLIC, AMBIENT_H3_HYPERBOLIC, AMBIENT_H4_HYPERBOLIC, AMBIENT_PROJECTIONS, AMBIENT_R1_EUCLIDEAN, AMBIENT_R2_EUCLIDEAN, AMBIENT_R3_EUCLIDEAN, AMBIENT_R4_EUCLIDEAN, AMBIENT_R5_EUCLIDEAN, AMBIENT_S1_SPHERE, AMBIENT_S2_SPHERE, AMBIENT_S3_SPHERE, AMBIENT_S4_SPHERE, AMBIENT_SPACES, BLEND_ALPHA, BLEND_MATERIAL, BLEND_REPLACE, FILTER_DIRECT, FILTER_LINEAR, FILTER_QUADRATIC, HAS_METHOD_MENU, INSPECTOR_CONTROL, INSPECTOR_CONTROL_EXT, INSPECTOR_MATERIAL, INSPECTOR_MATERIAL_EXT, INSPECTOR_TEXTURE, INSPECTOR_TEXTURE_EXT, LABEL_BASE, LABEL_CENTER, LABEL_HEAD, LABEL_MIDDLE, LABEL_TAIL, LABEL_TOP, m_numLabelTypes, METHOD_EXT, PERIODIC_BOTH, PERIODIC_HEIGHT, PERIODIC_NONE, PERIODIC_WIDTH, PROJ_KLEIN_BALL, PROJ_PARALLEL, PROJ_POINCARE_BALL, PROJ_STEREOGRAPHIC, PROJ_UPPER_HALFSPACE, SIDE_BACK, SIDE_BOTH, SIDE_FRONT, SIDE_NONE

Constructor Summary

Constructors

Constructor and Description
PgVectorField(int aVectorDim) Constructor of an empty vector field which is VERTEX_BASED on default.
PgVectorField(int aVectorDim, int basedOn) Constructor of an empty vector field which is VERTEX_BASED on default.

Method Summary

Modifier and Type	Method and Description
void	add(PgVectorField field) Add a vector field to this.
boolean	applyModelingMatrix() Multiply the modeling matrix to all vertices and vectors.
void	assureVectorColors() Ensure that array of colors for each vector exists and its size is equal to number of vectors.
boolean	blend(double s, PgGeometry ag, double t, PgGeometry bg) Blend between two vector fields this = s*a + t*b, e.g. used in interpolation.
void	clearTagVector(int anIndex, int aTag) Removes the given tag from a vector.
java.lang.Object	clone() Duplicate geometry by recursively cloning all instance variables except inspector panels and lists of registered listeners.
boolean	computeGradient(PgElementSet domain, PdVector image) Compute vector field as the gradient of a map from a domain triangulation to R.
boolean	computeGradient(PgElementSet domain, PdVector[] image, int coordinate) Compute vector field as the gradient (of one coordinate) of a map from a domain triangulation to R^n.
void	copy(PsObject object) Copy instance variables by duplication, not by copying a reference.
int	getBasedOn() Get flag whether vector field is vertex or element based.
int	getDimOfVectors() Get the dimension of vectors, i.e. the number of coordinates of each vector.
PgPointSet	getGeometry() If vector field lies on an element set, then this element set is delivered by this method (so the return value might in fact be an PgElementSet).
java.awt.Color	getGlobalVectorColor() Get global vector color which is used if no local colors are available.
double	getGlobalVectorLength() Get length factor of vectors when drawn in display.
double	getGlobalVectorSize() Get thickness in pixels of vectors when drawn in display.
int	getNumVectors() Get the number of used vectors.
PdVector	getVector(int anIndex) Returns a reference to one specific vector.
java.awt.Color[]	getVectorColors() Get array of vector colors.
PdVector[]	getVectors() Get vertex array for read and write access, but do not modify the size of any vector.
PdVector[]	getVertices() Get array of base vertices for read access.
void	init() Initializes and resets geometry.
boolean	isShowingIndividualMaterial() Get flag if this vector field uses its own material properties instead of inheriting material properties of the base geometry.
boolean	isShowingVectorArrows() Get flag if this vector field shows an arrow at the tip of each vector.
boolean	isShowingVectorColors() Determine whether showing of individual vector colors is enabled.
void	makeTangent() Projects the vectors into plane of their base elements (element based vector fields), or to the plane orthogonal to the vertex normal (vertex based vector fields, geometry must have vertex normals, otherwise this method simply returns).
boolean	merge(PgGeometryIf aField) Merge vector field with current object and store union of both objects in 'this'.
void	multScalar(double scalar) Scale all vectors in the field by a constant factor.
void	paint(PvGeometryIf dc) Major rendering method fills an internal container class supplied by the display.
PgGeometry	reflect(PdMatrix mat, boolean bOrient, boolean bVector) Generate a cloned geometry and transform vertices by a matrix.
boolean	removeVector(int anIndex)
void	setBasedOn(int basedOn) Specifies the number of vectors this instance can hold and alters the interpretation by the viewer (VERTEX_BASED vectors are shown at the vertices, ELEMENT_BASED vectors are shown at the element centers) and possibly other classes.
void	setDimOfVectors(int aDim) Sets the dimension of all vectors.
void	setGeometry(PgPointSet geom) Assign a geometry to serve as the carrier of this vector field.
void	setGlobalVectorColor(java.awt.Color color) Set global vector color to be used if no local colors are available.
void	setGlobalVectorLength(double length) Set length factor of vectors when drawn in display.
void	setGlobalVectorSize(double size) Set thickness in pixels of vectors when drawn in display.
void	setIndex(int ind) Set the index of this vector field.
void	setMaxNumVectors(int aNumVectors) All vector allocation should be done in 'setMaxNumVectors' method should not be called directly, only subclass#setMaxNumVectors() may call it.
void	setNumVectors(int numVectors) Set number of vectors.
void	setTagVector(int anIndex, int aTag) Sets the given tag for a vector.
void	setVector(int anIndex, double x) Sets vector at given index as scalar value, i.e. as 1-dim vector.
void	setVector(int anIndex, double x, double y) Sets vector at given index to the 2-dim vector (x,y).
void	setVector(int anIndex, double x, double y, double z) Sets vector at given index to the 3-dim vector (x,y,z).
boolean	setVector(int anIndex, PdVector aVector) Copies vector to vector field at specified index.
void	setVectorColors(java.awt.Color[] colorList) Copy vector colors of list to existing array of vector colors.
boolean	setVectors(PdVector[] aVectorList) Copy all vectors of vector list to an existing array of vectors.
void	showIndividualMaterial(boolean flag) Set flag if this vector field uses its own material properties instead of inheriting material properties of the base geometry.
void	showVectorArrows(boolean flag) Set flag if this vector field shows an arrow at the tip of each vector.
void	showVectorColors(boolean flag) Set flag to enable drawing of individual vector colors.
void	sub(PgVectorField field) Subtract vector fields, this = this - field.
java.lang.String	toString() Create a multi-line string representation with detailed information about all instance variables.
boolean	update(java.lang.Object event) Update the class whenever a child has changed.

Methods inherited from class jv.project.PgGeometry

addDisplay, addElement, addPolygon, addVertex, applyAmbientMatrix, clearTagElement, clearTagPolygon, clearTagVertex, convertWorldToModel, fillMethodMenu, fillMethodMenu, getAmbientBounds, getAmbientInvMatrix, getAmbientMatrix, getAmbientProjection, getAmbientSpace, getAuthorInfo, getAuthors, getBounds, getCenter, getCenterOfElement, getControlPanel, getDiameter, getDimOfSimplex, getDimOfVertices, getDisplayList, getDisplays, getElement, getGeometryInfo, getJvx, getLabelAttribute, getLabelColor, getLabelFont, getLabelSize, getLabelStyle, getMaterialPanel, getModelMatrix, getPolygon, getState, getTextureImage, getTextureImageName, getTitle, getType, getVersion, getVersionType, getVertex, hasAmbientMatrix, hasDisplay, hasModelMatrix, hasTagElement, hasTagPolygon, hasTagVertex, intersectionWithLine, isConfigurable, isEnabledInstanceSharing, isShowingBndBox, isShowingCenter, isShowingName, isShowingTitle, isVisible, projectFromAmbientSpace, removeDisplay, removeElement, removeMethodMenus, removePolygon, removeVertex, setAmbientMatrix, setAmbientProjection, setAmbientSpace, setAuthorInfo, setAuthors, setCenter, setDimOfSimplex, setDimOfVertices, setElement, setEnabledInstanceSharing, setGeometryInfo, setJvx, setLabelAttribute, setLabelAttribute, setLabelColor, setLabelFont, setLabelSize, setLabelStyle, setModelMatrix, setPolygon, setState, setTagElement, setTagPolygon, setTagVertex, setTextureImage, setTextureImageName, setTitle, setType, setVersion, setVersionType, setVertex, setVisible, showBndBox, showCenter, showName, showTitle

Methods inherited from class jv.object.PsObject

addInspector, addUpdateListener, assureInspector, clearTag, clone, clone, getFather, getInfoPanel, getInspector, getName, getNumObjects, getSymbol, hasInspector, hasTag, hasUpdateListener, instanceOf, instanceOf, newInspector, newInspector, removeInspector, removeInspector, removeUpdateListener, setName, setParent, setSymbol, setTag, updatePanels

Methods inherited from class java.lang.Object

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

Methods inherited from interface jv.project.PgGeometryIf

assureInspector, getInfoPanel, getName, hasTag, setName

Methods inherited from interface jv.object.PsUpdateIf

getFather, setParent

Field Detail

VERTEX_BASED

public static final int VERTEX_BASED

VectorField is given at vertices.

See Also:

Constant Field Values

ELEMENT_BASED

public static final int ELEMENT_BASED

VectorField is given at element centers.

See Also:

Constant Field Values

Constructor Detail

PgVectorField

public PgVectorField(int aVectorDim)

Constructor of an empty vector field which is VERTEX_BASED on default. The dimension of each vector may differ from the dimension of the underlying geometry.

Parameters:

aVectorDim - uniform number of components of all vectors

See Also:

PgVectorField(int, int)

PgVectorField

public PgVectorField(int aVectorDim,
                     int basedOn)

Constructor of an empty vector field which is VERTEX_BASED on default.

The parameter 'basedOn' must be VERTEX_BASED or ELEMENT_BASED. Specifies the number of vectors this instance can hold and alters the interpretation by the viewer (VERTEX_BASED vectors are shown at the vertices, ELEMENT_BASED vectors are shown at the element centers) and possibly other classes.

The dimension of each vector may differ from the dimension of the underlying geometry.

Parameters:

aVectorDim - uniform number of components of all vectors

basedOn - flag determining how to compute the vector base point from geometry

Version:

20.11.99, 1.00 created (ep)

Method Detail

init

public void init()

Description copied from class: PgGeometry

Initializes and resets geometry.

Overrides:

init in class PgGeometry

toString

public java.lang.String toString()

Create a multi-line string representation with detailed information about all instance variables.

Specified by:

toString in interface PgGeometryIf

Overrides:

toString in class PgGeometry

clone

public java.lang.Object clone()

Duplicate geometry by recursively cloning all instance variables except inspector panels and lists of registered listeners. The parent relationship is maintained only within this class but not to external classes. In general, all links of the clone to external objects are set to null.

Link to associated point set and element set is set to null.

Specified by:

clone in interface PgGeometryIf

Overrides:

clone in class PgGeometry

See Also:

copy(PsObject)

Version:

21.10.00, 1.00 created (kp)

copy

public void copy(PsObject object)

Copy instance variables by duplication, not by copying a reference.

The base surface and base points are kept unchanged, and they must typically be set by hand using setGeometry().

The argument was changed from PgGeometry to PsObject since there were problems in J/Link which preferred to use PsObject#copy(PsObject) instead of PgGeometry#copy(PsObject).

Overrides:

copy in class PgGeometry

See Also:

PsObject.clone()

Author:

Eike Preuss

Version:

08.11.02, 1.10 revised (kp) Argument changed to PsObject from PgGeometry.
26.06.00, 1.00 created (ep)

update

public boolean update(java.lang.Object event)

Update the class whenever a child has changed. Method is usually invoked from the children.

Specified by:

update in interface PsUpdateIf

Overrides:

update in class PgGeometry

Parameters:

event - carries a lot of information

Returns:

true if event has been handled, otherwise false

See Also:

PsObject.setParent(PsUpdateIf), PsObject.getFather(), PsObject.addUpdateListener(PsUpdateIf)

setGeometry

public void setGeometry(PgPointSet geom)

Assign a geometry to serve as the carrier of this vector field. If the vector field is element based then the geometry must be instance of class PgElementSet, if it is vertex based then the geometry must be instance of class PgPointSet.
You should probably also call addVectorField(PgVectorField) of the geometry.

HACK: Automatically adjust the number of vectors either to the number of vertices or elements of the geometry depending on the value of getBasedOn().

Version:

20.05.01, 2.00 revised (kp) Both setGeometry() methods merged. No longer adjust dimension of vectors.
20.11.99, 1.10 created (ep) Method setGeometry(PgElementSet).
00.00.98, 1.00 created (kp) Method setGeometry(PgPointSet).

getGeometry

public PgPointSet getGeometry()

If vector field lies on an element set, then this element set is delivered by this method (so the return value might in fact be an PgElementSet). Otherwise it returns the base points as a PgPointSet.

applyModelingMatrix

public boolean applyModelingMatrix()

Multiply the modeling matrix to all vertices and vectors. The modeling matrix of this geometry is set to the identity matrix.

Overrides:

applyModelingMatrix in class PgGeometry

Returns:

true if operation was applied successfully.

Since:

JavaView 2.36

Version:

04.09.02, 1.00 created (kp)

getBasedOn

public int getBasedOn()

Get flag whether vector field is vertex or element based.

Returns:

either VERTEX_BASED or ELEMENT_BASED

setBasedOn

public void setBasedOn(int basedOn)

Specifies the number of vectors this instance can hold and alters the interpretation by the viewer (VERTEX_BASED vectors are shown at the vertices, ELEMENT_BASED vectors are shown at the element centers) and possibly other classes.

Parameters:

basedOn - must be VERTEX_BASED or ELEMENT_BASED.

Version:

20.11.99, 1.00 created (ep)

getGlobalVectorLength

public double getGlobalVectorLength()

Get length factor of vectors when drawn in display.

getGlobalVectorSize

public double getGlobalVectorSize()

Get thickness in pixels of vectors when drawn in display.

getGlobalVectorColor

public java.awt.Color getGlobalVectorColor()

Get global vector color which is used if no local colors are available.

setGlobalVectorLength

public void setGlobalVectorLength(double length)

Set length factor of vectors when drawn in display.

setGlobalVectorSize

public void setGlobalVectorSize(double size)

Set thickness in pixels of vectors when drawn in display.

setGlobalVectorColor

public void setGlobalVectorColor(java.awt.Color color)

Set global vector color to be used if no local colors are available.

getVectors

public PdVector[] getVectors()

Get vertex array for read and write access, but do not modify the size of any vector. Note, that the actual size of the vector array may differ from getNumVectors() for efficiency reasons. Therefore, do not use vector.length but use getNumVectors().

setVectors

public boolean setVectors(PdVector[] aVectorList)

Copy all vectors of vector list to an existing array of vectors. Length of argument vector list must be equal or larger than getNumVectors(). All vectors are copied. The dimension of all argument vectors must be equal to PgPointSet.getDimOfVectors() of the geometry.

Dimension of vectors of this vector field is adjusted.

Parameters:

aVectorList - array with new vectors

isShowingVectorArrows

public boolean isShowingVectorArrows()

Get flag if this vector field shows an arrow at the tip of each vector.

Returns:

true if arrows are shown

Since:

JavaView 2.49.005

Version:

23.01.03, 1.00 created (kp)

showVectorArrows

public void showVectorArrows(boolean flag)

Set flag if this vector field shows an arrow at the tip of each vector.

Parameters:

flag - true if arrows are shown

Since:

JavaView 2.49.005

Version:

23.01.03, 1.00 created (kp)

isShowingIndividualMaterial

public boolean isShowingIndividualMaterial()

Get flag if this vector field uses its own material properties instead of inheriting material properties of the base geometry.

Returns:

true if individual material of this vector field is used

Since:

JavaView 2.49.005

Version:

23.01.03, 1.00 created (kp)

showIndividualMaterial

public void showIndividualMaterial(boolean flag)

Set flag if this vector field uses its own material properties instead of inheriting material properties of the base geometry.

Parameters:

flag - true if individual material of this vector field is used

Since:

JavaView 2.49.005

Version:

07.10.17, 1.10 revised (kp) Update showing of vector arrows.
23.01.03, 1.00 created (kp)

isShowingVectorColors

public boolean isShowingVectorColors()

Determine whether showing of individual vector colors is enabled.

showVectorColors

public void showVectorColors(boolean flag)

Set flag to enable drawing of individual vector colors.

assureVectorColors

public void assureVectorColors()

Ensure that array of colors for each vector exists and its size is equal to number of vectors.

Version:

19.07.00, 1.10 revised (kp) Allocate m_maxNumVectors colors instead of m_numVertices.

getVectorColors

public java.awt.Color[] getVectorColors()

Get array of vector colors.

setVectorColors

public void setVectorColors(java.awt.Color[] colorList)

Copy vector colors of list to existing array of vector colors. Length of argument list must be equal or larger than getNumVertices(). All vertex colors are copied. The dimension of all argument colors must be equal to getDimOfColors() of the geometry.

Parameters:

colorList - array with new vertex colors

getVertices

public PdVector[] getVertices()

Get array of base vertices for read access.

getDimOfVectors

public int getDimOfVectors()

Get the dimension of vectors, i.e. the number of coordinates of each vector. This number may differ from the dimension of the underlying geometry.

setMaxNumVectors

public void setMaxNumVectors(int aNumVectors)

All vector allocation should be done in 'setMaxNumVectors' method should not be called directly, only subclass#setMaxNumVectors() may call it. The user should change the number of vectors via setNumVectors().

Version:

22.06.07, 1.20 revised (kp) Method made public to allow better control of allocations.
19.07.00, 1.10 revised (kp) Adjust m_numVectors if smaller than new m_maxNumVectors.

getNumVectors

public int getNumVectors()

Get the number of used vectors.

setNumVectors

public void setNumVectors(int numVectors)

Set number of vectors. In general, the number should either be equal to the number of base vertices or base elements.

Version:

05.08.04, 1.60 revised (kp) No action if same number is requested.

setDimOfVectors

public void setDimOfVectors(int aDim)

Sets the dimension of all vectors. Higher entries are simply cut off. Additional entries are set to zero as in PdVector.

See Also:

PdVector.setSize(int)

setIndex

public void setIndex(int ind)

Set the index of this vector field. Method is solely used by the paint() method of the associated geometry.

paint

public void paint(PvGeometryIf dc)

Major rendering method fills an internal container class supplied by the display. This method is called by geometry container paint methods when they want this vector field to be displayed.

Specified by:

paint in interface PgGeometryIf

Overrides:

paint in class PgGeometry

See Also:

PgPointSet.paint(PvGeometryIf)

clearTagVector

public void clearTagVector(int anIndex,
                           int aTag)

Removes the given tag from a vector.

setTagVector

public void setTagVector(int anIndex,
                         int aTag)

Sets the given tag for a vector.

getVector

public PdVector getVector(int anIndex)

Returns a reference to one specific vector. Nevertheless you should use setVector(int, PdVector) to change values of vectors.

removeVector

public boolean removeVector(int anIndex)

setVector

public boolean setVector(int anIndex,
                         PdVector aVector)

Copies vector to vector field at specified index.

Parameters:

aVector - vector to be copied

anIndex - index beginning with 0

setVector

public void setVector(int anIndex,
                      double x)

Sets vector at given index as scalar value, i.e. as 1-dim vector.

Version:

21.02.04, 1.00 created (kp)

setVector

public void setVector(int anIndex,
                      double x,
                      double y)

Sets vector at given index to the 2-dim vector (x,y).

setVector

public void setVector(int anIndex,
                      double x,
                      double y,
                      double z)

Sets vector at given index to the 3-dim vector (x,y,z).

merge

public boolean merge(PgGeometryIf aField)

Merge vector field with current object and store union of both objects in 'this'. Number of vectors is the sum of both objects.

Specified by:

merge in interface PgGeometryIf

Overrides:

merge in class PgGeometry

Parameters:

aField - Vector field to be merged into 'this'

Returns:

true if method was successfull

Author:

Konrad Polthier

Version:

22.07.00, 1.10 revised (kp) Argument changed to class PgGeometryIf.
02.08.98, 1.00 created (kp)

blend

public boolean blend(double s,
                     PgGeometry ag,
                     double t,
                     PgGeometry bg)

Blend between two vector fields this = s*a + t*b, e.g. used in interpolation.

Specified by:

blend in interface PgGeometryIf

Overrides:

blend in class PgGeometry

Parameters:

s - weight of vertices of first geometry

ag - first geometry used for blending

t - weight of vertices of second geometry

bg - second geometry used for blending

Returns:

true on success

Author:

Konrad Polthier

Version:

29.02.04, 2.00 revised (kp) Full revision.
31.12.97, 1.00 created (kp)

computeGradient

public boolean computeGradient(PgElementSet domain,
                               PdVector[] image,
                               int coordinate)

Compute vector field as the gradient (of one coordinate) of a map from a domain triangulation to R^n. The image is given as an array of PdVectors, each vector is the image of the vertex of the domain with same index. The parameter coordinate specifies the coordinate of the image the gradient is computed from.

As a result the current vector field becomes the element based gradient of the map, tangential to triangles in the domain.

Parameters:

domain - domain triangulation, may be a curved surface

image - the image values of a vector-valued piecewise linear map at the vertices of the domain

coordinate - index of a coordinate component of the image the gradient is computed from

Version:

20.03.04, 1.20 revised (kh) Moved body to private method computeGradient(PgElementSet, PdVector, PdVector[], int) 01.03.04, 1.10 created (kh) Created from body of computeGradient(PgElementSet, PgPointSet, int).
25.11.99, 1.00 created (kp)

computeGradient

public boolean computeGradient(PgElementSet domain,
                               PdVector image)

Compute vector field as the gradient of a map from a domain triangulation to R. Image is given as a PdVector, each entry of the PdVector is the image of the vertex of the domain with same index.

As a result the current vector field becomes the element based gradient of the map, tangential to triangles in the domain.

Parameters:

domain - domain triangulation, may be a curved surface

image - the image values of a scalar-valued piecewise linear map at the vertices of the domain

Version:

20.03.04, 1.20 revised (kh) Moved body to private method computeGradient(PgElementSet, PdVector, PdVector[], int) 01.03.04, 1.10 revised (kh) Moved body form computeGradient(PgElementSet, PgPointSet, int).
25.11.99, 1.00 created (kp)

makeTangent

public void makeTangent()

Projects the vectors into plane of their base elements (element based vector fields), or to the plane orthogonal to the vertex normal (vertex based vector fields, geometry must have vertex normals, otherwise this method simply returns).

reflect

public PgGeometry reflect(PdMatrix mat,
                          boolean bOrient,
                          boolean bVector)

Generate a cloned geometry and transform vertices by a matrix. For example, this method is called to calculate mirror images of a geometry. Orientation of geometry affects surface vectors.

Specified by:

reflect in interface PgGeometryIf

Overrides:

reflect in class PgGeometry

Parameters:

mat - 3*3 or 4*4 transformation matrix

bOrient - flag whether to keep the orientation of the geometry

bVector - flag whether to keep the orientation of vectors

Returns:

new reflected copy of the geometry

Author:

Konrad Polthier

Version:

27.05.05, 1.00 created (kp)

multScalar

public void multScalar(double scalar)

Scale all vectors in the field by a constant factor.

Author:

Felix Kaelberer

Version:

19.09.2007, 1.00 created (fk)

sub

public void sub(PgVectorField field)

Subtract vector fields, this = this - field.

Since:

JavaView 3.90

Version:

01.09.09, 1.10 revised (fk) made non-static to be consistent with other add/sub-methods. 12.07.05, 1.00 created (kh)

add

public void add(PgVectorField field)

Add a vector field to this.

Since:

JavaView 3.99

Version:

01.09.09, 1.00 created (fk)