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Public Member Functions
Geom_OffsetSurface Class Reference

Describes an offset surface in 3D space.
An offset surface is defined by:
More...

#include <Geom_OffsetSurface.hxx>

Inheritance diagram for Geom_OffsetSurface:
Inheritance graph
[legend]

Public Member Functions

 Geom_OffsetSurface (const Handle< Geom_Surface > &S, const Standard_Real Offset)
 
 Constructs a surface offset from the basis surface <br>

S, where Offset is the distance between the offset
surface and the basis surface at any point.
A point on the offset surface is built by measuring
the offset value along a normal vector at a point on
S. This normal vector is given by the cross product
D1u^D1v, where D1u and D1v are the vectors
tangential to the basis surface in the u and v
parametric directions at this point. The side of S on
which the offset value is measured is indicated by
this normal vector if Offset is positive, or is the
inverse sense if Offset is negative.
Warnings :
More...

 
void SetBasisSurface (const Handle< Geom_Surface > &S)
 
 Raised if S is not at least C1. <br>

Warnings :
No check is done to verify that a unique normal direction is
defined at any point of the basis surface S.
Exceptions
Standard_ConstructionError if the surface S is not
at least "C1" continuous.
More...

 
void SetOffsetValue (const Standard_Real D)
 Changes this offset surface by assigning D as the offset value.
More...
 
Standard_Real Offset () const
 Returns the offset value of this offset surface.
More...
 
Handle_Geom_Surface BasisSurface () const
 
Returns the basis surface of this offset surface. <br>

Note: The basis surface can be an offset surface.
More...

 
void UReverse ()
 
 Changes the orientation of this offset surface in the u <br>

parametric direction. The bounds of the surface
are not changed but the given parametric direction is reversed.
More...

 
Standard_Real UReversedParameter (const Standard_Real U) const
 
 Computes the u  parameter on the modified <br>

surface, produced by reversing the u
parametric direction of this offset surface, for any
point of u parameter U on this offset surface.
More...

 
void VReverse ()
 
  Changes the orientation of this offset surface in the v parametric direction. The bounds of the surface <br>

are not changed but the given parametric direction is reversed.
More...

 
Standard_Real VReversedParameter (const Standard_Real V) const
 
 Computes the  v parameter on the modified <br>

surface, produced by reversing the or v
parametric direction of this offset surface, for any
point of v parameter V on this offset surface.
More...

 
void Bounds (Standard_Real &U1, Standard_Real &U2, Standard_Real &V1, Standard_Real &V2) const
 
 Returns the parametric bounds U1, U2, V1 and V2 of <br>

this offset surface.
If the surface is infinite, this function can return:
More...

 
GeomAbs_Shape Continuity () const
 
This method returns the continuity of the basis surface - 1. <br>

Continuity of the Offset surface :
C0 : only geometric continuity,
C1 : continuity of the first derivative all along the Surface,
C2 : continuity of the second derivative all along the Surface,
C3 : continuity of the third derivative all along the Surface,
CN : the order of continuity is infinite.
Example :
If the basis surface is C2 in the V direction and C3 in the U
direction Shape = C1.
Warnings :
If the basis surface has a unique normal direction defined at
any point this method gives the continuity of the offset
surface otherwise the effective continuity can be lower than
the continuity of the basis surface - 1.
More...

 
Standard_Boolean IsCNu (const Standard_Integer N) const
 This method answer True if the continuity of the basis surface
is N + 1 in the U parametric direction. We suppose in this
class that a unique normal is defined at any point on the basis
surface.
//! Raised if N <0.
More...
 
Standard_Boolean IsCNv (const Standard_Integer N) const
 This method answer True if the continuity of the basis surface
is N + 1 in the V parametric direction. We suppose in this
class that a unique normal is defined at any point on the basis
surface.
//! Raised if N <0.
More...
 
Standard_Boolean IsUClosed () const
 
 Checks whether this offset surface is closed in the u <br>

parametric direction.
Returns true if, taking uFirst and uLast as
the parametric bounds in the u parametric direction,
the distance between the points P(uFirst,v)
and P(uLast,v) is less than or equal to
gp::Resolution() for each value of the parameter v.
More...

 
Standard_Boolean IsVClosed () const
 
 Checks whether this offset surface is closed in the u <br>

or v parametric direction. Returns true if taking vFirst and vLast as the
parametric bounds in the v parametric direction, the
distance between the points P(u,vFirst) and
P(u,vLast) is less than or equal to
gp::Resolution() for each value of the parameter u.
More...

 
Standard_Boolean IsUPeriodic () const
 Returns true if this offset surface is periodic in the u
parametric direction, i.e. if the basis
surface of this offset surface is periodic in this direction.
More...
 
virtual Standard_Real UPeriod () const
 
 Returns the period of this offset surface in the u <br>

parametric direction respectively, i.e. the period of the
basis surface of this offset surface in this parametric direction.
//! raises if the surface is not uperiodic.
More...

 
Standard_Boolean IsVPeriodic () const
 Returns true if this offset surface is periodic in the v
parametric direction, i.e. if the basis
surface of this offset surface is periodic in this direction.
More...
 
virtual Standard_Real VPeriod () const
 
 Returns the period of this offset surface in the v <br>

parametric direction respectively, i.e. the period of the
basis surface of this offset surface in this parametric direction.
//! raises if the surface is not vperiodic.
More...

 
Handle_Geom_Curve UIso (const Standard_Real U) const
 Computes the U isoparametric curve.
More...
 
Handle_Geom_Curve VIso (const Standard_Real V) const
 
 Computes the V isoparametric curve. <br>

Te followings methods compute value and derivatives.

Warnings
An exception is raised if a unique normal vector is
not defined on the basis surface for the parametric
value (U,V).
No check is done at the creation time and we suppose
in this package that the offset surface can be defined
at any point.
More...

 
void D0 (const Standard_Real U, const Standard_Real V, gp_Pnt &P) const
 P (U, V) = Pbasis + Offset * Ndir where
Ndir = D1Ubasis ^ D1Vbasis / ||D1Ubasis ^ D1Vbasis|| is the
normal direction of the basis surface. Pbasis, D1Ubasis,
D1Vbasis are the point and the first derivatives on the basis
surface.
If Ndir is undefined this method computes an approched normal
direction using the following limited development :
Ndir = N0 + DNdir/DU + DNdir/DV + Eps with Eps->0 which
requires to compute the second derivatives on the basis surface.
If the normal direction cannot be approximate for this order
of derivation the exception UndefinedValue is raised.
Raised if the continuity of the basis surface is not C1.
Raised if the order of derivation required to compute the
normal direction is greater than the second order.
More...
 
void D1 (const Standard_Real U, const Standard_Real V, gp_Pnt &P, gp_Vec &D1U, gp_Vec &D1V) const
 Raised if the continuity of the basis surface is not C2.
More...
 
void D2 (const Standard_Real U, const Standard_Real V, gp_Pnt &P, gp_Vec &D1U, gp_Vec &D1V, gp_Vec &D2U, gp_Vec &D2V, gp_Vec &D2UV) const
 —Purpose ;
Raised if the continuity of the basis surface is not C3.
More...
 
void D3 (const Standard_Real U, const Standard_Real V, gp_Pnt &P, gp_Vec &D1U, gp_Vec &D1V, gp_Vec &D2U, gp_Vec &D2V, gp_Vec &D2UV, gp_Vec &D3U, gp_Vec &D3V, gp_Vec &D3UUV, gp_Vec &D3UVV) const
 Raised if the continuity of the basis surface is not C4.
More...
 
gp_Vec DN (const Standard_Real U, const Standard_Real V, const Standard_Integer Nu, const Standard_Integer Nv) const
 
Computes the derivative of order Nu in the direction u and Nv <br>

in the direction v.
//!—Purpose ;
Raised if the continuity of the basis surface is not CNu + 1
in the U direction and CNv + 1 in the V direction.
//! Raised if Nu + Nv < 1 or Nu < 0 or Nv < 0.
The following methods compute the value and derivatives
on the offset surface and returns the derivatives on the
basis surface too.
The computation of the value and derivatives on the basis
surface are used to evaluate the offset surface.

Warnings :
The exception UndefinedValue or UndefinedDerivative is
raised if it is not possible to compute a unique offset
direction.
More...

 
void Value (const Standard_Real U, const Standard_Real V, gp_Pnt &P, gp_Pnt &Pbasis, gp_Vec &D1Ubasis, gp_Vec &D1Vbasis) const
 P (U, V) = Pbasis + Offset * Ndir where
Ndir = D1Ubasis ^ D1Vbasis / ||D1Ubasis ^ D1Vbasis|| is
the normal direction of the surface.
If Ndir is undefined this method computes an approched normal
direction using the following limited development :
Ndir = N0 + DNdir/DU + DNdir/DV + Eps with Eps->0 which
requires to compute the second derivatives on the basis surface.
If the normal direction cannot be approximate for this order
of derivation the exception UndefinedValue is raised.
Raised if the continuity of the basis surface is not C1.
Raised if the order of derivation required to compute the normal
direction is greater than the second order.
More...
 
void D1 (const Standard_Real U, const Standard_Real V, gp_Pnt &P, gp_Pnt &Pbasis, gp_Vec &D1U, gp_Vec &D1V, gp_Vec &D1Ubasis, gp_Vec &D1Vbasis, gp_Vec &D2Ubasis, gp_Vec &D2Vbasis, gp_Vec &D2UVbasis) const
 Raised if the continuity of the basis surface is not C2.
More...
 
void D2 (const Standard_Real U, const Standard_Real V, gp_Pnt &P, gp_Pnt &Pbasis, gp_Vec &D1U, gp_Vec &D1V, gp_Vec &D2U, gp_Vec &D2V, gp_Vec &D2UV, gp_Vec &D1Ubasis, gp_Vec &D1Vbasis, gp_Vec &D2Ubasis, gp_Vec &D2Vbasis, gp_Vec &D2UVbasis, gp_Vec &D3Ubasis, gp_Vec &D3Vbasis, gp_Vec &D3UUVbasis, gp_Vec &D3UVVbasis) const
 Raised if the continuity of the basis surface is not C3.
//! The following private methods
includes common part of local and global methods
of derivative evaluations.
More...
 
void LocalD0 (const Standard_Real U, const Standard_Real V, const Standard_Integer USide, const Standard_Integer VSide, gp_Pnt &P) const
 
void LocalD1 (const Standard_Real U, const Standard_Real V, const Standard_Integer USide, const Standard_Integer VSide, gp_Pnt &P, gp_Vec &D1U, gp_Vec &D1V) const
 
void LocalD2 (const Standard_Real U, const Standard_Real V, const Standard_Integer USide, const Standard_Integer VSide, gp_Pnt &P, gp_Vec &D1U, gp_Vec &D1V, gp_Vec &D2U, gp_Vec &D2V, gp_Vec &D2UV) const
 
void LocalD3 (const Standard_Real U, const Standard_Real V, const Standard_Integer USide, const Standard_Integer VSide, gp_Pnt &P, gp_Vec &D1U, gp_Vec &D1V, gp_Vec &D2U, gp_Vec &D2V, gp_Vec &D2UV, gp_Vec &D3U, gp_Vec &D3V, gp_Vec &D3UUV, gp_Vec &D3UVV) const
 
gp_Vec LocalDN (const Standard_Real U, const Standard_Real V, const Standard_Integer USide, const Standard_Integer VSide, const Standard_Integer Nu, const Standard_Integer Nv) const
 
void Transform (const gp_Trsf &T)
 Applies the transformation T to this offset surface.
Note: the basis surface is also modified.
More...
 
virtual void TransformParameters (Standard_Real &U, Standard_Real &V, const gp_Trsf &T) const
 
 Computes the  parameters on the  transformed  surface for <br>
     the transform of the point of parameters U,V on <me>. <br>


me->Transformed(T)->Value(U',V')

is the same point as

me->Value(U,V).Transformed(T)

Where U',V' are the new values of U,V after calling

me->TranformParameters(U,V,T)
This methods calls the basis surface method.
More...

 
virtual gp_GTrsf2d ParametricTransformation (const gp_Trsf &T) const
 
 Returns a 2d transformation  used to find the  new <br>
     parameters of a point on the transformed surface. <br>


me->Transformed(T)->Value(U',V')

is the same point as

me->Value(U,V).Transformed(T)

Where U',V' are obtained by transforming U,V with
th 2d transformation returned by

me->ParametricTransformation(T)

This methods calls the basis surface method.
More...

 
Handle_Geom_Geometry Copy () const
 Creates a new object which is a copy of this offset surface.
More...
 
Handle_Geom_Surface Surface () const
 returns an equivalent surface of the offset surface
when the basis surface is a canonic surface or a
rectangular limited surface on canonic surface or if
the offset is null.
More...
 
Standard_Boolean UOsculatingSurface (const Standard_Real U, const Standard_Real V, Standard_Boolean &IsOpposite, Handle< Geom_BSplineSurface > &UOsculSurf) const
 
 if Standard_True, L is  the local osculating surface <br>
     along U at  the point U,V.   It means that  DL/DU is <br>
     collinear to DS/DU .  If IsOpposite == Standard_True <br>
     these vectors have opposite direction. <br>


More...

 
Standard_Boolean VOsculatingSurface (const Standard_Real U, const Standard_Real V, Standard_Boolean &IsOpposite, Handle< Geom_BSplineSurface > &VOsculSurf) const
 if Standard_True, L is the local osculating surface
along V at the point U,V.
It means that DL/DV is
collinear to DS/DV . If IsOpposite == Standard_True
these vectors have opposite direction.
More...
 
- Public Member Functions inherited from Geom_Surface
Handle_Geom_Surface UReversed () const
 Reverses the U direction of parametrization of <me>.
The bounds of the surface are not modified.
A copy of <me> is returned.
More...
 
Handle_Geom_Surface VReversed () const
 Reverses the V direction of parametrization of <me>.
The bounds of the surface are not modified.
A copy of <me> is returned.
More...
 
gp_Pnt Value (const Standard_Real U, const Standard_Real V) const
 
Computes the point of parameter U on the surface. <br>


It is implemented with D0
Raised only for an "OffsetSurface" if it is not possible to
compute the current point.
More...

 
- Public Member Functions inherited from Geom_Geometry
void Mirror (const gp_Pnt &P)
 Performs the symmetrical transformation of a Geometry
with respect to the point P which is the center of the
symmetry.
More...
 
void Mirror (const gp_Ax1 &A1)
 Performs the symmetrical transformation of a Geometry
with respect to an axis placement which is the axis of the
symmetry.
More...
 
void Mirror (const gp_Ax2 &A2)
 Performs the symmetrical transformation of a Geometry
with respect to a plane. The axis placement A2 locates
the plane of the symmetry : (Location, XDirection, YDirection).
More...
 
void Rotate (const gp_Ax1 &A1, const Standard_Real Ang)
 Rotates a Geometry. A1 is the axis of the rotation.
Ang is the angular value of the rotation in radians.
More...
 
void Scale (const gp_Pnt &P, const Standard_Real S)
 Scales a Geometry. S is the scaling value.
More...
 
void Translate (const gp_Vec &V)
 Translates a Geometry. V is the vector of the tanslation.
More...
 
void Translate (const gp_Pnt &P1, const gp_Pnt &P2)
 Translates a Geometry from the point P1 to the point P2.
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Handle_Geom_Geometry Mirrored (const gp_Pnt &P) const
 
Handle_Geom_Geometry Mirrored (const gp_Ax1 &A1) const
 
Handle_Geom_Geometry Mirrored (const gp_Ax2 &A2) const
 
Handle_Geom_Geometry Rotated (const gp_Ax1 &A1, const Standard_Real Ang) const
 
Handle_Geom_Geometry Scaled (const gp_Pnt &P, const Standard_Real S) const
 
Handle_Geom_Geometry Transformed (const gp_Trsf &T) const
 
Handle_Geom_Geometry Translated (const gp_Vec &V) const
 
Handle_Geom_Geometry Translated (const gp_Pnt &P1, const gp_Pnt &P2) const
 
- Public Member Functions inherited from MMgt_TShared
virtual void Delete () const
 Memory deallocator for transient classes. More...
 
- Public Member Functions inherited from Standard_Transient
 Standard_Transient ()
 Empty constructor. More...
 
 Standard_Transient (const Standard_Transient &)
 Copy constructor – does nothing. More...
 
Standard_Transient & operator= (const Standard_Transient &)
 Assignment operator, needed to avoid copying reference counter. More...
 
virtual ~Standard_Transient ()
 Destructor must be virtual. More...
 
virtual void ShallowDump (Standard_OStream &) const
 
virtual const
Handle_Standard_Type & 		DynamicType () const
 Returns a type information object about this object. More...
 
Standard_Boolean IsInstance (const Handle_Standard_Type &theType) const
 Returns a true value if this is an instance of Type. More...
 
Standard_Boolean IsInstance (const Standard_CString theTypeName) const
 Returns a true value if this is an instance of TypeName. More...
 
Standard_Boolean IsKind (const Handle_Standard_Type &theType) const
 Returns true if this is an instance of Type or an instance of any class that inherits from Type. Note that multiple inheritance is not supported by OCCT RTTI mechanism. More...
 
Standard_Boolean IsKind (const Standard_CString theTypeName) const
 Returns true if this is an instance of TypeName or an instance of any class that inherits from TypeName. Note that multiple inheritance is not supported by OCCT RTTI mechanism. More...
 
virtual Handle_Standard_Transient This () const
 Returns a Handle which references this object. Must never be called to objects created in stack. More...
 
Standard_Integer GetRefCount () const
 Get the reference counter of this object. More...
 

Detailed Description

Describes an offset surface in 3D space.
An offset surface is defined by:

Constructor & Destructor Documentation

Geom_OffsetSurface::Geom_OffsetSurface ( const Handle< Geom_Surface > &  S,
const Standard_Real  Offset 
) 

 Constructs a surface offset from the basis surface <br>

S, where Offset is the distance between the offset
surface and the basis surface at any point.
A point on the offset surface is built by measuring
the offset value along a normal vector at a point on
S. This normal vector is given by the cross product
D1u^D1v, where D1u and D1v are the vectors
tangential to the basis surface in the u and v
parametric directions at this point. The side of S on
which the offset value is measured is indicated by
this normal vector if Offset is positive, or is the
inverse sense if Offset is negative.
Warnings :

  • The offset surface is built with a copy of the
    surface S. Therefore, when S is modified the
    offset surface is not modified.
  • No check is made at the time of construction to
    detect points on S with multiple possible normal directions.
    //! Raised if S is not at least C1.
    Warnings :
    No check is done to verify that a unique normal direction is
    defined at any point of the basis surface S.

Member Function Documentation

Handle_Geom_Surface Geom_OffsetSurface::BasisSurface ( ) const 

Returns the basis surface of this offset surface. <br>

Note: The basis surface can be an offset surface.

void Geom_OffsetSurface::Bounds ( Standard_Real &  U1,
Standard_Real &  U2,
Standard_Real &  V1,
Standard_Real &  V2 
) const
virtual 

 Returns the parametric bounds U1, U2, V1 and V2 of <br>

this offset surface.
If the surface is infinite, this function can return:

  • Standard_Real::RealFirst(), or
  • Standard_Real::RealLast().

Implements Geom_Surface.

GeomAbs_Shape Geom_OffsetSurface::Continuity ( ) const
virtual 

This method returns the continuity of the basis surface - 1. <br>

Continuity of the Offset surface :
C0 : only geometric continuity,
C1 : continuity of the first derivative all along the Surface,
C2 : continuity of the second derivative all along the Surface,
C3 : continuity of the third derivative all along the Surface,
CN : the order of continuity is infinite.
Example :
If the basis surface is C2 in the V direction and C3 in the U
direction Shape = C1.
Warnings :
If the basis surface has a unique normal direction defined at
any point this method gives the continuity of the offset
surface otherwise the effective continuity can be lower than
the continuity of the basis surface - 1.

Implements Geom_Surface.

Handle_Geom_Geometry Geom_OffsetSurface::Copy ( ) const
virtual

Creates a new object which is a copy of this offset surface.

Implements Geom_Geometry.

void Geom_OffsetSurface::D0 ( const Standard_Real  U,
const Standard_Real  V,
gp_Pnt &  P 
) const
virtual

P (U, V) = Pbasis + Offset * Ndir where
Ndir = D1Ubasis ^ D1Vbasis / ||D1Ubasis ^ D1Vbasis|| is the
normal direction of the basis surface. Pbasis, D1Ubasis,
D1Vbasis are the point and the first derivatives on the basis
surface.
If Ndir is undefined this method computes an approched normal
direction using the following limited development :
Ndir = N0 + DNdir/DU + DNdir/DV + Eps with Eps->0 which
requires to compute the second derivatives on the basis surface.
If the normal direction cannot be approximate for this order
of derivation the exception UndefinedValue is raised.
Raised if the continuity of the basis surface is not C1.
Raised if the order of derivation required to compute the
normal direction is greater than the second order.

Implements Geom_Surface.

void Geom_OffsetSurface::D1 ( const Standard_Real  U,
const Standard_Real  V,
gp_Pnt &  P,
gp_Vec &  D1U,
gp_Vec &  D1V 
) const
virtual

Raised if the continuity of the basis surface is not C2.

Implements Geom_Surface.

void Geom_OffsetSurface::D1 ( const Standard_Real  U,
const Standard_Real  V,
gp_Pnt &  P,
gp_Pnt &  Pbasis,
gp_Vec &  D1U,
gp_Vec &  D1V,
gp_Vec &  D1Ubasis,
gp_Vec &  D1Vbasis,
gp_Vec &  D2Ubasis,
gp_Vec &  D2Vbasis,
gp_Vec &  D2UVbasis 
) const

Raised if the continuity of the basis surface is not C2.

void Geom_OffsetSurface::D2 ( const Standard_Real  U,
const Standard_Real  V,
gp_Pnt &  P,
gp_Vec &  D1U,
gp_Vec &  D1V,
gp_Vec &  D2U,
gp_Vec &  D2V,
gp_Vec &  D2UV 
) const
virtual

—Purpose ;
Raised if the continuity of the basis surface is not C3.

Implements Geom_Surface.

void Geom_OffsetSurface::D2 ( const Standard_Real  U,
const Standard_Real  V,
gp_Pnt &  P,
gp_Pnt &  Pbasis,
gp_Vec &  D1U,
gp_Vec &  D1V,
gp_Vec &  D2U,
gp_Vec &  D2V,
gp_Vec &  D2UV,
gp_Vec &  D1Ubasis,
gp_Vec &  D1Vbasis,
gp_Vec &  D2Ubasis,
gp_Vec &  D2Vbasis,
gp_Vec &  D2UVbasis,
gp_Vec &  D3Ubasis,
gp_Vec &  D3Vbasis,
gp_Vec &  D3UUVbasis,
gp_Vec &  D3UVVbasis 
) const

Raised if the continuity of the basis surface is not C3.
//! The following private methods
includes common part of local and global methods
of derivative evaluations.

void Geom_OffsetSurface::D3 ( const Standard_Real  U,
const Standard_Real  V,
gp_Pnt &  P,
gp_Vec &  D1U,
gp_Vec &  D1V,
gp_Vec &  D2U,
gp_Vec &  D2V,
gp_Vec &  D2UV,
gp_Vec &  D3U,
gp_Vec &  D3V,
gp_Vec &  D3UUV,
gp_Vec &  D3UVV 
) const
virtual

Raised if the continuity of the basis surface is not C4.

Implements Geom_Surface.

gp_Vec Geom_OffsetSurface::DN ( const Standard_Real  U,
const Standard_Real  V,
const Standard_Integer  Nu,
const Standard_Integer  Nv 
) const
virtual 

Computes the derivative of order Nu in the direction u and Nv <br>

in the direction v.
//!—Purpose ;
Raised if the continuity of the basis surface is not CNu + 1
in the U direction and CNv + 1 in the V direction.
//! Raised if Nu + Nv < 1 or Nu < 0 or Nv < 0.
The following methods compute the value and derivatives
on the offset surface and returns the derivatives on the
basis surface too.
The computation of the value and derivatives on the basis
surface are used to evaluate the offset surface.

Warnings :
The exception UndefinedValue or UndefinedDerivative is
raised if it is not possible to compute a unique offset
direction.

Implements Geom_Surface.

Standard_Boolean Geom_OffsetSurface::IsCNu ( const Standard_Integer  N) const
virtual

This method answer True if the continuity of the basis surface
is N + 1 in the U parametric direction. We suppose in this
class that a unique normal is defined at any point on the basis
surface.
//! Raised if N <0.

Implements Geom_Surface.

Standard_Boolean Geom_OffsetSurface::IsCNv ( const Standard_Integer  N) const
virtual

This method answer True if the continuity of the basis surface
is N + 1 in the V parametric direction. We suppose in this
class that a unique normal is defined at any point on the basis
surface.
//! Raised if N <0.

Implements Geom_Surface.

Standard_Boolean Geom_OffsetSurface::IsUClosed ( ) const
virtual 

 Checks whether this offset surface is closed in the u <br>

parametric direction.
Returns true if, taking uFirst and uLast as
the parametric bounds in the u parametric direction,
the distance between the points P(uFirst,v)
and P(uLast,v) is less than or equal to
gp::Resolution() for each value of the parameter v.

Implements Geom_Surface.

Standard_Boolean Geom_OffsetSurface::IsUPeriodic ( ) const
virtual

Returns true if this offset surface is periodic in the u
parametric direction, i.e. if the basis
surface of this offset surface is periodic in this direction.

Implements Geom_Surface.

Standard_Boolean Geom_OffsetSurface::IsVClosed ( ) const
virtual 

 Checks whether this offset surface is closed in the u <br>

or v parametric direction. Returns true if taking vFirst and vLast as the
parametric bounds in the v parametric direction, the
distance between the points P(u,vFirst) and
P(u,vLast) is less than or equal to
gp::Resolution() for each value of the parameter u.

Implements Geom_Surface.

Standard_Boolean Geom_OffsetSurface::IsVPeriodic ( ) const
virtual

Returns true if this offset surface is periodic in the v
parametric direction, i.e. if the basis
surface of this offset surface is periodic in this direction.

Implements Geom_Surface.

void Geom_OffsetSurface::LocalD0 ( const Standard_Real  U,
const Standard_Real  V,
const Standard_Integer  USide,
const Standard_Integer  VSide,
gp_Pnt &  P 
) const
void Geom_OffsetSurface::LocalD1 ( const Standard_Real  U,
const Standard_Real  V,
const Standard_Integer  USide,
const Standard_Integer  VSide,
gp_Pnt &  P,
gp_Vec &  D1U,
gp_Vec &  D1V 
) const
void Geom_OffsetSurface::LocalD2 ( const Standard_Real  U,
const Standard_Real  V,
const Standard_Integer  USide,
const Standard_Integer  VSide,
gp_Pnt &  P,
gp_Vec &  D1U,
gp_Vec &  D1V,
gp_Vec &  D2U,
gp_Vec &  D2V,
gp_Vec &  D2UV 
) const
void Geom_OffsetSurface::LocalD3 ( const Standard_Real  U,
const Standard_Real  V,
const Standard_Integer  USide,
const Standard_Integer  VSide,
gp_Pnt &  P,
gp_Vec &  D1U,
gp_Vec &  D1V,
gp_Vec &  D2U,
gp_Vec &  D2V,
gp_Vec &  D2UV,
gp_Vec &  D3U,
gp_Vec &  D3V,
gp_Vec &  D3UUV,
gp_Vec &  D3UVV 
) const
gp_Vec Geom_OffsetSurface::LocalDN ( const Standard_Real  U,
const Standard_Real  V,
const Standard_Integer  USide,
const Standard_Integer  VSide,
const Standard_Integer  Nu,
const Standard_Integer  Nv 
) const
Standard_Real Geom_OffsetSurface::Offset ( ) const

Returns the offset value of this offset surface.

virtual gp_GTrsf2d Geom_OffsetSurface::ParametricTransformation ( const gp_Trsf &  T) const
virtual 

 Returns a 2d transformation  used to find the  new <br>
     parameters of a point on the transformed surface. <br>


me->Transformed(T)->Value(U',V')

is the same point as

me->Value(U,V).Transformed(T)

Where U',V' are obtained by transforming U,V with
th 2d transformation returned by

me->ParametricTransformation(T)

This methods calls the basis surface method.

Reimplemented from Geom_Surface.

void Geom_OffsetSurface::SetBasisSurface ( const Handle< Geom_Surface > &  S) 

 Raised if S is not at least C1. <br>

Warnings :
No check is done to verify that a unique normal direction is
defined at any point of the basis surface S.
Exceptions
Standard_ConstructionError if the surface S is not
at least "C1" continuous.

void Geom_OffsetSurface::SetOffsetValue ( const Standard_Real  D)

Changes this offset surface by assigning D as the offset value.

Handle_Geom_Surface Geom_OffsetSurface::Surface ( ) const

returns an equivalent surface of the offset surface
when the basis surface is a canonic surface or a
rectangular limited surface on canonic surface or if
the offset is null.

void Geom_OffsetSurface::Transform ( const gp_Trsf &  T)
virtual

Applies the transformation T to this offset surface.
Note: the basis surface is also modified.

Implements Geom_Geometry.

virtual void Geom_OffsetSurface::TransformParameters ( Standard_Real &  U,
Standard_Real &  V,
const gp_Trsf &  T 
) const
virtual 

 Computes the  parameters on the  transformed  surface for <br>
     the transform of the point of parameters U,V on <me>. <br>


me->Transformed(T)->Value(U',V')

is the same point as

me->Value(U,V).Transformed(T)

Where U',V' are the new values of U,V after calling

me->TranformParameters(U,V,T)
This methods calls the basis surface method.

Reimplemented from Geom_Surface.

Handle_Geom_Curve Geom_OffsetSurface::UIso ( const Standard_Real  U) const
virtual

Computes the U isoparametric curve.

Implements Geom_Surface.

Standard_Boolean Geom_OffsetSurface::UOsculatingSurface ( const Standard_Real  U,
const Standard_Real  V,
Standard_Boolean &  IsOpposite,
Handle< Geom_BSplineSurface > &  UOsculSurf 
) const 

 if Standard_True, L is  the local osculating surface <br>
     along U at  the point U,V.   It means that  DL/DU is <br>
     collinear to DS/DU .  If IsOpposite == Standard_True <br>
     these vectors have opposite direction. <br>


virtual Standard_Real Geom_OffsetSurface::UPeriod ( ) const
virtual 

 Returns the period of this offset surface in the u <br>

parametric direction respectively, i.e. the period of the
basis surface of this offset surface in this parametric direction.
//! raises if the surface is not uperiodic.

Reimplemented from Geom_Surface.

void Geom_OffsetSurface::UReverse ( )
virtual 

 Changes the orientation of this offset surface in the u <br>

parametric direction. The bounds of the surface
are not changed but the given parametric direction is reversed.

Implements Geom_Surface.

Standard_Real Geom_OffsetSurface::UReversedParameter ( const Standard_Real  U) const
virtual 

 Computes the u  parameter on the modified <br>

surface, produced by reversing the u
parametric direction of this offset surface, for any
point of u parameter U on this offset surface.

Implements Geom_Surface.

void Geom_OffsetSurface::Value ( const Standard_Real  U,
const Standard_Real  V,
gp_Pnt &  P,
gp_Pnt &  Pbasis,
gp_Vec &  D1Ubasis,
gp_Vec &  D1Vbasis 
) const

P (U, V) = Pbasis + Offset * Ndir where
Ndir = D1Ubasis ^ D1Vbasis / ||D1Ubasis ^ D1Vbasis|| is
the normal direction of the surface.
If Ndir is undefined this method computes an approched normal
direction using the following limited development :
Ndir = N0 + DNdir/DU + DNdir/DV + Eps with Eps->0 which
requires to compute the second derivatives on the basis surface.
If the normal direction cannot be approximate for this order
of derivation the exception UndefinedValue is raised.
Raised if the continuity of the basis surface is not C1.
Raised if the order of derivation required to compute the normal
direction is greater than the second order.

Handle_Geom_Curve Geom_OffsetSurface::VIso ( const Standard_Real  V) const
virtual 

 Computes the V isoparametric curve. <br>

Te followings methods compute value and derivatives.

Warnings
An exception is raised if a unique normal vector is
not defined on the basis surface for the parametric
value (U,V).
No check is done at the creation time and we suppose
in this package that the offset surface can be defined
at any point.

Implements Geom_Surface.

Standard_Boolean Geom_OffsetSurface::VOsculatingSurface ( const Standard_Real  U,
const Standard_Real  V,
Standard_Boolean &  IsOpposite,
Handle< Geom_BSplineSurface > &  VOsculSurf 
) const

if Standard_True, L is the local osculating surface
along V at the point U,V.
It means that DL/DV is
collinear to DS/DV . If IsOpposite == Standard_True
these vectors have opposite direction.

virtual Standard_Real Geom_OffsetSurface::VPeriod ( ) const
virtual 

 Returns the period of this offset surface in the v <br>

parametric direction respectively, i.e. the period of the
basis surface of this offset surface in this parametric direction.
//! raises if the surface is not vperiodic.

Reimplemented from Geom_Surface.

void Geom_OffsetSurface::VReverse ( )
virtual 

  Changes the orientation of this offset surface in the v parametric direction. The bounds of the surface <br>

are not changed but the given parametric direction is reversed.

Implements Geom_Surface.

Standard_Real Geom_OffsetSurface::VReversedParameter ( const Standard_Real  V) const
virtual 

 Computes the  v parameter on the modified <br>

surface, produced by reversing the or v
parametric direction of this offset surface, for any
point of v parameter V on this offset surface.

Implements Geom_Surface.

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