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PLib::HNurbsSurface Class Template Reference

A hierarchichal NURBS surface class. More...

#include <hnurbsS.h>

Inheritance diagram for PLib::HNurbsSurface:

List of all members.

Public Methods
	HNurbsSurface ()
	HNurbsSurface (const NurbsSurface< T, N > &S)
	HNurbsSurface (const HNurbsSurface< T, N > &S)
	HNurbsSurface (HNurbsSurface< T, N > *base)
	HNurbsSurface (HNurbsSurface< T, N > *base, const Vector< T > &xU, const Vector< T > &xV)
	HNurbsSurface (HNurbsSurface< T, N > *base, const HNurbsSurface< T, N > &surf)
virtual	~HNurbsSurface ()
HNurbsSurface< T, N > *	baseLevel () const
HNurbsSurface< T, N > *	nextLevel () const
HNurbsSurface< T, N > *	firstLevel () const
HNurbsSurface< T, N > *	lastLevel () const
void	splitUV (int nu, int nv, Vector< T > &nU, Vector< T > &nV)
void	splitUV (int nu, int su, int nv, int sv, Vector< T > &nU, Vector< T > &nV)
virtual HNurbsSurface< T, N > *	addLevel (int nsplit)
virtual HNurbsSurface< T, N > *	addLevel ()
virtual void	copy (const HNurbsSurface< T, N > &nS)
int	modifies (T u, T v)
HPoint_nD< T, N >	operator() (T u, T v) const
HPoint_nD< T, N >	hpointAt (T u, T v, int lod=-1) const
void	deriveAtH (T u, T v, int, Matrix< HPoint_nD< T, N > > &, int lod=-1) const
void	deriveAt (T u, T v, int, Matrix< Point_nD< T, N > > &, int lod=-1) const
int	movePointOffset (T u, T v, const Point_nD< T, N > &delta)
void	scale (const Point_nD< T, N > &s)
int	initBase (int force=0)
virtual void	updateSurface (int i0=-1, int j0=-1)
virtual void	updateLevels (int updateLevel=-1)
int	isoCurveU (T u, NurbsCurve< T, N > &c, int lod=-1) const
int	isoCurveV (T v, NurbsCurve< T, N > &c, int lod=-1) const
int	read (const char *filename)
int	write (const char *filename) const
virtual int	read (ifstream &fin)
int	write (ofstream &fout) const
int	level () const
int	maxLevel () const
int	modifiedN () const
void	refineKnots (const Vector< T > &nU, const Vector< T > &nV)
void	refineKnotU (const Vector< T > &X)
void	refineKnotV (const Vector< T > &X)
void	axis (int i, int j, Point_nD< T, N > &xaxis, Point_nD< T, N > &yaxis, Point_nD< T, N > &zaxis) const
void	setFixedOffsetVector (const Point_nD< T, N > &I, const Point_nD< T, N > &J, const Point_nD< T, N > &K)
void	setVariableOffsetVector ()
Public Attributes
Matrix< HPoint_nD< T, N > >	offset
Vector< T >	rU
Vector< T >	rV
Protected Attributes
NurbsSurface< T, N >	baseSurf
HNurbsSurface< T, N > *	baseLevel_
HNurbsSurface< T, N > *	nextLevel_
HNurbsSurface< T, N > *	firstLevel_
HNurbsSurface< T, N > *	lastLevel_
Matrix< Point_nD< T, N > >	ivec
Matrix< Point_nD< T, N > >	jvec
Matrix< Point_nD< T, N > >	kvec
int	level_
int	updateN
int	baseUpdateN
int	update_
T	uS_
T	uE_
T	vS_
T	vE_
T	uD
T	vD
int	fixedOffset

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Detailed Description

template<class T, int N>
class PLib::HNurbsSurface< T, N >

A hierarchichal NURBS surface class.

This class can represent and manipulate a hierarchical NURBS surface. The surface is composed of points in homogenous space. It can have any degree and have any number of control points.

This does not correspond to the HBsplines given by Forsey. However I hope that it will be usefull for interactive manipulations of NURBS surfaces.

Other aspects of my implementation are different. They will be documented when the class is fully functionnal.

Presently there is only a limited set of functions available for this class. And honestly, until I can optimize the space requirement of the class I don't think you should build anything critical with a HNurbsSurface.

Author:

Philippe Lavoie

Date:

28 September 1997

Definition at line 60 of file hnurbsS.h.

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Constructor & Destructor Documentation

template<class T, int N> PLib::HNurbsSurface< T, N >::HNurbsSurface (    )

The basic constructor. Author: Philippe Lavoie Date: 7 October 1997 Definition at line 39 of file hnurbsS.cpp. Referenced by addLevel, and copy.

template<class T, int N> PLib::HNurbsSurface< T, N >::HNurbsSurface (  const NurbsSurface< T, N > &    S )

Constructs a base HNURBS. Constructs a base HNURBS. This HNURBS surface is set to level 0. And it corresponds to the NURBS surface. This constructor does not transform the NURBS surface into a HNURBS surface. It only copies the values from the NURBS surface as it's base offset values. Parameters: S  the NURBS surface at level 0 Author: Philippe Lavoie Date: 7 October 1997 Definition at line 190 of file hnurbsS.cpp. References PLib::NurbsSurface::P.

template<class T, int N> PLib::HNurbsSurface< T, N >::HNurbsSurface (  const HNurbsSurface< T, N > &    S )

The copy constructor. Parameters: S  the HNURBS surface to copy Author: Philippe Lavoie Date: 7 October 1997 Definition at line 215 of file hnurbsS.cpp. References copy.

template<class T, int N> PLib::HNurbsSurface< T, N >::HNurbsSurface (  HNurbsSurface< T, N > *    base )

Constructor with a base level. Parameters: base  the base level xU  the U knots to insert in this level xV  the V knots to insert in this level Warning: The base pointer must be pointing to a valid object Author: Philippe Lavoie Date: 7 October 1997 Definition at line 129 of file hnurbsS.cpp. References PLib::NurbsSurface::degU, PLib::NurbsSurface::degV, initBase, PLib::NurbsSurface::P, PLib::NurbsSurface::U, and PLib::NurbsSurface::V.

template<class T, int N> PLib::HNurbsSurface< T, N >::HNurbsSurface (  HNurbsSurface< T, N > *    base, const Vector< T > &    xU, const Vector< T > &    xV )

Constructor with a base level. Parameters: base  the base level xU  the U knots to insert in this level xV  the V knots to insert in this level Warning: The base pointer must be pointing to a valid object Author: Philippe Lavoie Date: 7 October 1997 Definition at line 66 of file hnurbsS.cpp. References PLib::NurbsSurface::degU, PLib::NurbsSurface::degV, initBase, PLib::NurbsSurface::P, PLib::NurbsSurface::U, and PLib::NurbsSurface::V.

template<class T, int N> PLib::HNurbsSurface< T, N >::HNurbsSurface (  HNurbsSurface< T, N > *    base, const HNurbsSurface< T, N > &    surf )

A level constructor. Parameters: base  the base of this level the  values for this new level Warning: The base pointer must be pointing to a valid object Author: Philippe Lavoie Date: 7 October 1997 Definition at line 245 of file hnurbsS.cpp. References copy, and initBase.

template<class T, int N> PLib::HNurbsSurface< T, N >::~HNurbsSurface (    )  [virtual]

Destructor. Deletes all the levels. Author: Philippe Lavoie Date: 7 October 1997 Definition at line 685 of file hnurbsS.cpp.

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Member Function Documentation

template<class T, int N> HNurbsSurface< T, N > * PLib::HNurbsSurface< T, N >::addLevel (    )  [virtual]

Adds a level to this HNURBS surface. Parameters: n  the number of new knots between each knots. Returns: a pointer to the new level or 0 if there was an error. Warning: returns 0, if there is already a nextlevel. Author: Philippe Lavoie Date: 7 October 1997 Reimplemented in PLib::HNurbsSurfaceSP. Definition at line 897 of file hnurbsS.cpp. References HNurbsSurface. Referenced by read.

template<class T, int N> HNurbsSurface< T, N > * PLib::HNurbsSurface< T, N >::addLevel (  int    n )  [virtual]

Adds a level to this HNURBS surface. Parameters: n  the number of new knots between each knots. Returns: a pointer to the new level or 0 if there was an error. Warning: returns 0, if there is already a nextlevel. Author: Philippe Lavoie Date: 7 October 1997 Definition at line 869 of file hnurbsS.cpp. References HNurbsSurface, and splitUV.

template<class T, int N> void PLib::HNurbsSurface< T, N >::copy (  const HNurbsSurface< T, N > &    nS )  [virtual]

Copies a HNurbs Surface and all it children. Parameters: ns  the HNurbs surface to copy Author: Philippe Lavoie Date: 7 October 1997 Reimplemented in PLib::HNurbsSurfaceSP. Definition at line 292 of file hnurbsS.cpp. References HNurbsSurface. Referenced by HNurbsSurface.

template<class T, int N> void PLib::HNurbsSurface< T, N >::deriveAt (  T    u, T    v, int    d, Matrix< Point_nD< T, N > > &    ders, int    lod = -1 )  const

Finds the derivative of the point (u,v). Computes the matrix of derivatives at u,v. The value of skl(k,l) represents the derivative of the surface S(u,v) with respect to u, k times and to v, l times. Parameters: u  the u parametric value v  the v parametric value ders  the Matrix of derivatives. Author: Philippe Lavoie Date: 7 October 1997 Definition at line 662 of file hnurbsS.cpp.

template<class T, int N> void PLib::HNurbsSurface< T, N >::deriveAtH (  T    u, T    v, int    d, Matrix< HPoint_nD< T, N > > &    ders, int    lod = -1 )  const

Finds the derivative of the point (u,v). Computes the matrix of derivatives at (u,v) . The value of skl(k,l) represents the derivative of the surface $S(u,v)$ with respect to u, k times and to v, l times. Parameters: u  the u parametric value v  the v parametric value ders  the Matrix of derivatives. Author: Philippe Lavoie Date: 7 October 1997 Definition at line 632 of file hnurbsS.cpp.

template<class T, int N> HPoint_nD< T, N > PLib::HNurbsSurface< T, N >::hpointAt (  T    u, T    v, int    lod = -1 )  const

finds the homogenous point at (u,v) for a certain level of detail. Parameters: u  the u parametric value v  the v parametric value lod  the level of detail3 Returns: the homogenous point at (u,v) and at the level of detail specivied by lod. Author: Philippe Lavoie Date: 7 October 1997 Definition at line 588 of file hnurbsS.cpp. Referenced by PLib::HNurbsSurface< float, N >::operator().

template<class T, int N> int PLib::HNurbsSurface< T, N >::initBase (  int    force = 0 )

Initialize the base surface. Initialize the base surface from the previous level if it has been modified. Parameters: force  if set, this forces an update of the base surface Returns: 1 if the base surface is modified, 0 otherwise. Author: Philippe Lavoie Date: 15 April 1998 Definition at line 411 of file hnurbsS.cpp. Referenced by HNurbsSurface, refineKnots, setFixedOffsetVector, setVariableOffsetVector, PLib::HNurbsSurfaceSP::updateSurface, and updateSurface.

template<class T, int N> int PLib::HNurbsSurface< T, N >::isoCurveU (  T    u, NurbsCurve< T, N > &    c, int    lod = -1 )  const

generates an iso curve in the U direction. Generates an iso-parametric curve which goes through the parametric value u along the U direction. Parameters: u  the U parametric value c  the iso-parametric curve lod  the level of detail to draw the curve with Returns: 0 if an error occured, 1 otherwise. Warning: the parametric value u must be in a valid range Author: Philippe Lavoie Date: 7 October, 1997 Definition at line 926 of file hnurbsS.cpp.

template<class T, int N> int PLib::HNurbsSurface< T, N >::isoCurveV (  T    v, NurbsCurve< T, N > &    c, int    lod = -1 )  const

generates an iso curve in the V direction. Generates an iso-parametric curve which goes through the parametric value v along the V direction. Parameters: v  the V parametric value c  the iso-parametric curve lod  the level of detail to draw the curve with Returns: 0 if an error occured, 1 otherwise Warning: the parametric value v must be in a valid range Author: Philippe Lavoie Date: 7 October, 1997 Definition at line 959 of file hnurbsS.cpp.

template<class T, int N> int PLib::HNurbsSurface< T, N >::maxLevel (    )  const

the maximum level of detail. Finds the maximum level of detail available from this HNURBS surface Returns: the maximum level of detail. Author: Philippe Lavoie Date: 7 October 1997 Definition at line 610 of file hnurbsS.cpp.

template<class T, int N> int PLib::HNurbsSurface< T, N >::modifies (  T    u, T    v )

Specifies the level that modifies the point. Specifies what level modifies the point (u,v) Parameters: u  the u parametric value v  the v parametric value Author: Philippe Lavoie Date: 7 October 1997 Definition at line 550 of file hnurbsS.cpp. References PLib::NurbsSurface::degU, PLib::NurbsSurface::degV, PLib::NurbsSurface::findSpanU, PLib::NurbsSurface::findSpanV, PLib::NurbsSurface::knotU, and PLib::NurbsSurface::knotV.

template<class T, int N> int PLib::HNurbsSurface< T, N >::movePointOffset (  T    u, T    v, const Point_nD< T, N > &    delta )

Move a point on the surface. This moves the point s(u,v) by delta. As this is a HNURBS surface. It moves the offset surface by delta, it doesn't move the surface point per say. Parameters: u  the parameter in the u direction v  the parameter in the v direction delta  the displacement of the point s(u,v) Returns: 1 if the operation was succesfull, 0 otherwise Warning: u and v must be in a valid range. Author: Philippe Lavoie Date: 3 June 1998 Definition at line 1372 of file hnurbsS.cpp. References PLib::NurbsSurface::P, and updateSurface.

template<class T, int N> HPoint_nD<T,N> PLib::HNurbsSurface< T, N >::operator() (  T    u, T    v )  const [inline, virtual]

Returns the point on the surface at u,v. Returns the point on the surface at u,v Parameters: u  the u parametric value v  the v parametric value Returns: The homogenous point at u,v Author: Philippe Lavoie Date: 24 January, 1997 Reimplemented from PLib::NurbsSurface. Definition at line 86 of file hnurbsS.h.

template<class T, int N> int PLib::HNurbsSurface< T, N >::read (  ifstream &    fin )  [virtual]

Read a HNURBS surface from a file stream. Parameters: fin  the input file stream Returns: 0 if an error occurs, 1 otherwise Author: Philippe Lavoie Date: 7 October 1997 Reimplemented from PLib::NurbsSurface. Reimplemented in PLib::HNurbsSurfaceSP. Definition at line 988 of file hnurbsS.cpp. References addLevel, PLib::NurbsSurface::P, PLib::NurbsSurface::resize, PLib::NurbsSurface::U, updateSurface, and PLib::NurbsSurface::V.

template<class T, int N> int PLib::HNurbsSurface< T, N >::read (  const char *    filename )

Reads a HNURBS surface from a file. Parameters: filename  the filename to read from Returns: 0 if an error occurs, 1 otherwise Author: Philippe Lavoie Date: 7 October 1997 Reimplemented from PLib::NurbsSurface. Reimplemented in PLib::HNurbsSurfaceGL. Definition at line 1123 of file hnurbsS.cpp.

template<class T, int N> void PLib::HNurbsSurface< T, N >::refineKnots (  const Vector< T > &    nU, const Vector< T > &    nV )  [virtual]

Refine both knot vectors. Parameters: nU  the U knot vector to refine from nV  the V knot vector to refine from Author: Philippe Lavoie Date: 24 January, 1997 Reimplemented from PLib::NurbsSurface. Reimplemented in PLib::HNurbsSurfaceSP. Definition at line 1260 of file hnurbsS.cpp. References initBase, refineKnotU, and refineKnotV.

template<class T, int N> void PLib::HNurbsSurface< T, N >::refineKnotU (  const Vector< T > &    X )  [virtual]

Refines the U knot vector. Parameters: X  the knot vector to refine from Author: Philippe Lavoie Date: 24 January, 1997 Reimplemented from PLib::NurbsSurface. Reimplemented in PLib::HNurbsSurfaceSP. Definition at line 1279 of file hnurbsS.cpp. References PLib::NurbsSurface::degU, PLib::NurbsSurface::degV, PLib::NurbsSurface::U, updateSurface, and PLib::NurbsSurface::V. Referenced by refineKnots.

template<class T, int N> void PLib::HNurbsSurface< T, N >::refineKnotV (  const Vector< T > &    X )  [virtual]

Refines the V knot vector. Parameters: X  the knot vector to refine from Author: Philippe Lavoie Date: 24 January, 1997 Reimplemented from PLib::NurbsSurface. Reimplemented in PLib::HNurbsSurfaceSP. Definition at line 1321 of file hnurbsS.cpp. References PLib::NurbsSurface::degU, PLib::NurbsSurface::degV, PLib::NurbsSurface::U, updateSurface, and PLib::NurbsSurface::V. Referenced by refineKnots.

template<class T, int N> void PLib::HNurbsSurface< T, N >::scale (  const Point_nD< T, N > &    s )

Scales the object. Parameters: s  the scaling factor Author: Philippe Lavoie Date: 11 June 1998 Definition at line 1409 of file hnurbsS.cpp.

template<class T, int N> void PLib::HNurbsSurface< T, N >::setFixedOffsetVector (  const Point_nD< T, N > &    I, const Point_nD< T, N > &    J, const Point_nD< T, N > &    K )

The offset vector are fixed. Fixes the offset vector direction to a unique value. The offset vector's direction won't depend on its base layer. Parameters: I  the i vector J  the j vector K  the k vector Author: Philippe Lavoie Date: 11 June 1998 Definition at line 1437 of file hnurbsS.cpp. References initBase, and updateSurface.

template<class T, int N> void PLib::HNurbsSurface< T, N >::setVariableOffsetVector (    )

The offset vector are variable. Fixes the offsset vector direction to a variable value. The value depends on its base layer. Author: Philippe Lavoie Date: 11 June 1998 Definition at line 1457 of file hnurbsS.cpp. References initBase, and updateSurface.

template<class T, int N> void PLib::HNurbsSurface< T, N >::splitUV (  int    nu, int    su, int    nv, int    sv, Vector< T > &    nU, Vector< T > &    nV )

Insert n knots betwen each knots. Insert nu knots betwen each knots in the U vector and nv knots between each knots in the V vector. This doesn't not perform a split. It just generates a suitable rU and rV vector. It is suggested that splitting should be done for the level above, not the local level. Parameters: nu  the number of new knots between each knots in U. su  the multiplicity of the each new knot in U nv  the number of new knots between each knots in V. sv  the multiplicity of the each new knot in V nU  the new refinement knot vector in U nV  the new refinement knot vector in V Author: Philippe Lavoie Date: 7 October 1997 Definition at line 803 of file hnurbsS.cpp. References PLib::NurbsSurface::degU, PLib::NurbsSurface::degV, PLib::NurbsSurface::knotU, and PLib::NurbsSurface::knotV.

template<class T, int N> void PLib::HNurbsSurface< T, N >::splitUV (  int    nu, int    nv, Vector< T > &    nU, Vector< T > &    nV )

Insert n knots betwen each knots. Insert nu knots betwen each knots in the U vector and nv knots between each knots in the V vector. This does not perform a split. It just generates a suitable rU and rV vector. It is suggested that splitting should be done for the level above, not the local level. Parameters: nu  the number of new knots between each knots in U. nv  the number of new knots between each knots in V. nU  the new refinement knot vector in U nV  the new refinement knot vector in V Author: Philippe Lavoie Date: 7 October 1997 Definition at line 743 of file hnurbsS.cpp. References PLib::NurbsSurface::knotU, and PLib::NurbsSurface::knotV. Referenced by PLib::HNurbsSurfaceSP::addLevel, and addLevel.

template<class T, int N> void PLib::HNurbsSurface< T, N >::updateLevels (  int    upLevel = -1 )  [virtual]

Update the surface for all the levels. Parameters: upLevel  updates the levels up to this level of detail Author: Philippe Lavoie Date: 7 October 1997 Reimplemented in PLib::HNurbsSurfaceSP. Definition at line 707 of file hnurbsS.cpp. References updateSurface.

template<class T, int N> void PLib::HNurbsSurface< T, N >::updateSurface (  int    i0 = -1, int    j0 = -1 )  [virtual]

updates the NURBS surface. Updates the NURBS surface according to the offset values and its base level. You can update only one control point from the surface if you specify a value for i and j or you can update all the points if i0 or j0 is below 0. Parameters: i0  the row of the control point to update j0  the column of the control point to update Author: Philippe Lavoie Date: 7 October 1997 Reimplemented in PLib::HNurbsSurfaceSP. Definition at line 330 of file hnurbsS.cpp. References PLib::NurbsSurface::degU, PLib::NurbsSurface::degV, initBase, PLib::NurbsSurface::P, PLib::NurbsSurface::U, and PLib::NurbsSurface::V. Referenced by movePointOffset, read, refineKnotU, refineKnotV, setFixedOffsetVector, setVariableOffsetVector, and updateLevels.

template<class T, int N> int PLib::HNurbsSurface< T, N >::write (  ofstream &    fout )  const

Write a HNURBS surface to a file stream. Parameters: fout  the output filestream to write to. Returns: 1 on success, 0 on failure Author: Philippe Lavoie Date: 7 October 1997 Reimplemented from PLib::NurbsSurface. Reimplemented in PLib::HNurbsSurfaceGL. Definition at line 1143 of file hnurbsS.cpp. References PLib::NurbsSurface::degU, PLib::NurbsSurface::degV, PLib::NurbsSurface::P, PLib::NurbsSurface::U, and PLib::NurbsSurface::V.

template<class T, int N> int PLib::HNurbsSurface< T, N >::write (  const char *    filename )  const

write a HNURBS surface to a file. Parameters: filename  the filename to write to Returns: 1 on success, 0 on failure Author: Philippe Lavoie Date: 7 October 1997 Reimplemented from PLib::NurbsSurface. Reimplemented in PLib::HNurbsSurfaceGL. Definition at line 1219 of file hnurbsS.cpp.

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

• hnurbsS.h
• hnurbsS.cpp

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