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Public Member Functions
Geom2d_TrimmedCurve Class Reference

Defines a portion of a curve limited by two values of <br>

parameters inside the parametric domain of the curve.
The trimmed curve is defined by:
More...

#include <Geom2d_TrimmedCurve.hxx>

Inheritance diagram for Geom2d_TrimmedCurve:
Inheritance graph
[legend]

Public Member Functions

 Geom2d_TrimmedCurve (const Handle< Geom2d_Curve > &C, const Standard_Real U1, const Standard_Real U2, const Standard_Boolean Sense=Standard_True)
 
Creates a trimmed curve from the basis curve C limited between <br>

U1 and U2.

. U1 can be greater or lower than U2.
. The returned curve is oriented from U1 to U2.
. If the basis curve C is periodic there is an ambiguity
because two parts are available. In this case by default
the trimmed curve has the same orientation as the basis
curve (Sense = True). If Sense = False then the orientation
of the trimmed curve is opposite to the orientation of the
basis curve C.
If the curve is closed but not periodic it is not possible
to keep the part of the curve including the junction point
(except if the junction point is at the beginning or
at the end of the trimmed curve) because you could lose the
fundamental characteristics of the basis curve which are
used for example to compute the derivatives of the trimmed
curve. So for a closed curve the rules are the same as for
a open curve.
Warnings :
In this package the entities are not shared. The TrimmedCurve is
built with a copy of the curve C. So when C is modified the
TrimmedCurve is not modified
Warnings :
If is periodic, parametrics bounds of the TrimmedCurve,
can be different to [<U1>;<U2>}, if <U1> or <U2> are not in the
principal period.
Include :
For more explanation see the scheme given with this class.
Raises ConstructionError the C is not periodic and U1 or U2 are out of
the bounds of C.
Raised if U1 = U2.
More...

 
void Reverse ()
 
Changes the direction of parametrization of <me>. The first and <br>

the last parametric values are modified. The "StartPoint"
of the initial curve becomes the "EndPoint" of the reversed
curve and the "EndPoint" of the initial curve becomes the
"StartPoint" of the reversed curve.
Example - If the trimmed curve is defined by:
More...

 
Standard_Real ReversedParameter (const Standard_Real U) const
 
 Returns the  parameter on the  reversed  curve for <br>
     the point of parameter U on <me>. <br>


returns UFirst + ULast - U
More...

 
void SetTrim (const Standard_Real U1, const Standard_Real U2, const Standard_Boolean Sense=Standard_True)
 
 Changes this trimmed curve, by redefining the <br>

parameter values U1 and U2, which limit its basis curve.
Note: If the basis curve is periodic, the trimmed curve
has the same orientation as the basis curve if Sense
is true (default value) or the opposite orientation if Sense is false.
Warning
If the basis curve is periodic, the bounds of the
trimmed curve may be different from U1 and U2 if the
parametric origin of the basis curve is within the arc
of the trimmed curve. In this case, the modified
parameter will be equal to U1 or U2 plus or minus the period.
Exceptions
Standard_ConstructionError if:
More...

 
Handle_Geom2d_Curve BasisCurve () const
 
 Returns the basis curve. <br>

Warning
This function does not return a constant reference.
Consequently, any modification of the returned value
directly modifies the trimmed curve.
More...

 
GeomAbs_Shape Continuity () const
 
Returns the global continuity of the basis curve of this trimmed curve. <br>

C0 : only geometric continuity,
C1 : continuity of the first derivative all along the Curve,
C2 : continuity of the second derivative all along the Curve,
C3 : continuity of the third derivative all along the Curve,
CN : the order of continuity is infinite.
More...

 
Standard_Boolean IsCN (const Standard_Integer N) const
 — Purpose
Returns True if the order of continuity of the
trimmed curve is N. A trimmed curve is at least "C0" continuous.
Warnings :
The continuity of the trimmed curve can be greater than
the continuity of the basis curve because you consider
only a part of the basis curve.
//! Raised if N < 0.
More...
 
gp_Pnt2d EndPoint () const
 Returns the end point of <me>. This point is the
evaluation of the curve for the "LastParameter".
More...
 
Standard_Real FirstParameter () const
 Returns the value of the first parameter of <me>.
The first parameter is the parameter of the "StartPoint"
of the trimmed curve.
More...
 
Standard_Boolean IsClosed () const
 Returns True if the distance between the StartPoint and
the EndPoint is lower or equal to Resolution from package
gp.
More...
 
Standard_Boolean IsPeriodic () const
 Returns true if the basis curve of this trimmed curve is periodic.
More...
 
virtual Standard_Real Period () const
 
 Returns the period of the basis curve of this trimmed curve. <br>

Exceptions
Standard_NoSuchObject if the basis curve is not periodic.
More...

 
Standard_Real LastParameter () const
 Returns the value of the last parameter of <me>.
The last parameter is the parameter of the "EndPoint" of the
trimmed curve.
More...
 
gp_Pnt2d StartPoint () const
 
Returns the start point of <me>. <br>

This point is the evaluation of the curve from the
"FirstParameter".
//! value and derivatives
Warnings :
The returned derivatives have the same orientation as the
derivatives of the basis curve.
More...

 
void D0 (const Standard_Real U, gp_Pnt2d &P) const
 If the basis curve is an OffsetCurve sometimes it is not
possible to do the evaluation of the curve at the parameter
U (see class OffsetCurve).
More...
 
void D1 (const Standard_Real U, gp_Pnt2d &P, gp_Vec2d &V1) const
 Raised if the continuity of the curve is not C1.
More...
 
void D2 (const Standard_Real U, gp_Pnt2d &P, gp_Vec2d &V1, gp_Vec2d &V2) const
 Raised if the continuity of the curve is not C2.
More...
 
void D3 (const Standard_Real U, gp_Pnt2d &P, gp_Vec2d &V1, gp_Vec2d &V2, gp_Vec2d &V3) const
 Raised if the continuity of the curve is not C3.
More...
 
gp_Vec2d DN (const Standard_Real U, const Standard_Integer N) const
 
 For the point of parameter U of this trimmed curve, <br>

computes the vector corresponding to the Nth derivative.
Warning
The returned derivative vector has the same
orientation as the derivative vector of the basis curve,
even if the trimmed curve does not have the same
orientation as the basis curve.
Exceptions
Standard_RangeError if N is less than 1.
//! geometric transformations
More...

 
void Transform (const gp_Trsf2d &T)
 
 Applies the transformation T to this trimmed curve. <br>

Warning The basis curve is also modified.
More...

 
virtual Standard_Real TransformedParameter (const Standard_Real U, const gp_Trsf2d &T) const
 
 Returns the  parameter on the  transformed  curve for <br>
     the transform of the point of parameter U on <me>. <br>


me->Transformed(T)->Value(me->TransformedParameter(U,T))

is the same point as

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

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

 
virtual Standard_Real ParametricTransformation (const gp_Trsf2d &T) const
 
 Returns a  coefficient to compute the parameter on <br>
     the transformed  curve  for  the transform  of the <br>
     point on <me>. <br>


Transformed(T)->Value(U * ParametricTransformation(T))

is the same point as

Value(U).Transformed(T)

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

 
Handle_Geom2d_Geometry Copy () const
 Creates a new object, which is a copy of this trimmed curve.
More...
 
- Public Member Functions inherited from Geom2d_Curve
Handle_Geom2d_Curve Reversed () const
 
 Creates a reversed duplicate Changes the orientation of this curve. The first and <br>

last parameters are not changed, but the parametric
direction of the curve is reversed.
If the curve is bounded:
More...

 
gp_Pnt2d Value (const Standard_Real U) const
 
 Computes the point of parameter U on <me>. <br>

If the curve is periodic then the returned point is P(U) with
U = Ustart + (U - Uend) where Ustart and Uend are the
parametric bounds of the curve.

it is implemented with D0.
Raised only for the "OffsetCurve" if it is not possible to
compute the current point. For example when the first
derivative on the basis curve and the offset direction
are parallel.
More...

 
- Public Member Functions inherited from Geom2d_Geometry
void Mirror (const gp_Pnt2d &P)
 
Performs the symmetrical transformation of a Geometry <br>

with respect to the point P which is the center of the
symmetry and assigns the result to this geometric object.
More...

 
void Mirror (const gp_Ax2d &A)
 
Performs the symmetrical transformation of a Geometry <br>

with respect to an axis placement which is the axis of the symmetry.
More...

 
void Rotate (const gp_Pnt2d &P, const Standard_Real Ang)
 
Rotates a Geometry. P is the center of the rotation. <br>

Ang is the angular value of the rotation in radians.
More...

 
void Scale (const gp_Pnt2d &P, const Standard_Real S)
 Scales a Geometry. S is the scaling value.
More...
 
void Translate (const gp_Vec2d &V)
 Translates a Geometry. V is the vector of the tanslation.
More...
 
void Translate (const gp_Pnt2d &P1, const gp_Pnt2d &P2)
 Translates a Geometry from the point P1 to the point P2.
More...
 
Handle_Geom2d_Geometry Mirrored (const gp_Pnt2d &P) const
 
Handle_Geom2d_Geometry Mirrored (const gp_Ax2d &A) const
 
Handle_Geom2d_Geometry Rotated (const gp_Pnt2d &P, const Standard_Real Ang) const
 
Handle_Geom2d_Geometry Scaled (const gp_Pnt2d &P, const Standard_Real S) const
 
Handle_Geom2d_Geometry Transformed (const gp_Trsf2d &T) const
 
Handle_Geom2d_Geometry Translated (const gp_Vec2d &V) const
 
Handle_Geom2d_Geometry Translated (const gp_Pnt2d &P1, const gp_Pnt2d &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_Transientoperator= (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

Defines a portion of a curve limited by two values of <br>

parameters inside the parametric domain of the curve.
The trimmed curve is defined by:

Constructor & Destructor Documentation

Geom2d_TrimmedCurve::Geom2d_TrimmedCurve ( const Handle< Geom2d_Curve > &  C,
const Standard_Real  U1,
const Standard_Real  U2,
const Standard_Boolean  Sense = Standard_True 
)

Creates a trimmed curve from the basis curve C limited between <br>

U1 and U2.

. U1 can be greater or lower than U2.
. The returned curve is oriented from U1 to U2.
. If the basis curve C is periodic there is an ambiguity
because two parts are available. In this case by default
the trimmed curve has the same orientation as the basis
curve (Sense = True). If Sense = False then the orientation
of the trimmed curve is opposite to the orientation of the
basis curve C.
If the curve is closed but not periodic it is not possible
to keep the part of the curve including the junction point
(except if the junction point is at the beginning or
at the end of the trimmed curve) because you could lose the
fundamental characteristics of the basis curve which are
used for example to compute the derivatives of the trimmed
curve. So for a closed curve the rules are the same as for
a open curve.
Warnings :
In this package the entities are not shared. The TrimmedCurve is
built with a copy of the curve C. So when C is modified the
TrimmedCurve is not modified
Warnings :
If is periodic, parametrics bounds of the TrimmedCurve,
can be different to [<U1>;<U2>}, if <U1> or <U2> are not in the
principal period.
Include :
For more explanation see the scheme given with this class.
Raises ConstructionError the C is not periodic and U1 or U2 are out of
the bounds of C.
Raised if U1 = U2.

Member Function Documentation

Handle_Geom2d_Curve Geom2d_TrimmedCurve::BasisCurve ( ) const

 Returns the basis curve. <br>

Warning
This function does not return a constant reference.
Consequently, any modification of the returned value
directly modifies the trimmed curve.

GeomAbs_Shape Geom2d_TrimmedCurve::Continuity ( ) const
virtual

Returns the global continuity of the basis curve of this trimmed curve. <br>

C0 : only geometric continuity,
C1 : continuity of the first derivative all along the Curve,
C2 : continuity of the second derivative all along the Curve,
C3 : continuity of the third derivative all along the Curve,
CN : the order of continuity is infinite.

Implements Geom2d_Curve.

Handle_Geom2d_Geometry Geom2d_TrimmedCurve::Copy ( ) const
virtual

Creates a new object, which is a copy of this trimmed curve.

Implements Geom2d_Geometry.

void Geom2d_TrimmedCurve::D0 ( const Standard_Real  U,
gp_Pnt2d P 
) const
virtual

If the basis curve is an OffsetCurve sometimes it is not
possible to do the evaluation of the curve at the parameter
U (see class OffsetCurve).

Implements Geom2d_Curve.

void Geom2d_TrimmedCurve::D1 ( const Standard_Real  U,
gp_Pnt2d P,
gp_Vec2d V1 
) const
virtual

Raised if the continuity of the curve is not C1.

Implements Geom2d_Curve.

void Geom2d_TrimmedCurve::D2 ( const Standard_Real  U,
gp_Pnt2d P,
gp_Vec2d V1,
gp_Vec2d V2 
) const
virtual

Raised if the continuity of the curve is not C2.

Implements Geom2d_Curve.

void Geom2d_TrimmedCurve::D3 ( const Standard_Real  U,
gp_Pnt2d P,
gp_Vec2d V1,
gp_Vec2d V2,
gp_Vec2d V3 
) const
virtual

Raised if the continuity of the curve is not C3.

Implements Geom2d_Curve.

gp_Vec2d Geom2d_TrimmedCurve::DN ( const Standard_Real  U,
const Standard_Integer  N 
) const
virtual

 For the point of parameter U of this trimmed curve, <br>

computes the vector corresponding to the Nth derivative.
Warning
The returned derivative vector has the same
orientation as the derivative vector of the basis curve,
even if the trimmed curve does not have the same
orientation as the basis curve.
Exceptions
Standard_RangeError if N is less than 1.
//! geometric transformations

Implements Geom2d_Curve.

gp_Pnt2d Geom2d_TrimmedCurve::EndPoint ( ) const
virtual

Returns the end point of <me>. This point is the
evaluation of the curve for the "LastParameter".

Implements Geom2d_BoundedCurve.

Standard_Real Geom2d_TrimmedCurve::FirstParameter ( ) const
virtual

Returns the value of the first parameter of <me>.
The first parameter is the parameter of the "StartPoint"
of the trimmed curve.

Implements Geom2d_Curve.

Standard_Boolean Geom2d_TrimmedCurve::IsClosed ( ) const
virtual

Returns True if the distance between the StartPoint and
the EndPoint is lower or equal to Resolution from package
gp.

Implements Geom2d_Curve.

Standard_Boolean Geom2d_TrimmedCurve::IsCN ( const Standard_Integer  N) const
virtual

— Purpose
Returns True if the order of continuity of the
trimmed curve is N. A trimmed curve is at least "C0" continuous.
Warnings :
The continuity of the trimmed curve can be greater than
the continuity of the basis curve because you consider
only a part of the basis curve.
//! Raised if N < 0.

Implements Geom2d_Curve.

Standard_Boolean Geom2d_TrimmedCurve::IsPeriodic ( ) const
virtual

Returns true if the basis curve of this trimmed curve is periodic.

Implements Geom2d_Curve.

Standard_Real Geom2d_TrimmedCurve::LastParameter ( ) const
virtual

Returns the value of the last parameter of <me>.
The last parameter is the parameter of the "EndPoint" of the
trimmed curve.

Implements Geom2d_Curve.

virtual Standard_Real Geom2d_TrimmedCurve::ParametricTransformation ( const gp_Trsf2d T) const
virtual

 Returns a  coefficient to compute the parameter on <br>
     the transformed  curve  for  the transform  of the <br>
     point on <me>. <br>


Transformed(T)->Value(U * ParametricTransformation(T))

is the same point as

Value(U).Transformed(T)

This methods calls the basis curve method.

Reimplemented from Geom2d_Curve.

virtual Standard_Real Geom2d_TrimmedCurve::Period ( ) const
virtual

 Returns the period of the basis curve of this trimmed curve. <br>

Exceptions
Standard_NoSuchObject if the basis curve is not periodic.

Reimplemented from Geom2d_Curve.

void Geom2d_TrimmedCurve::Reverse ( )
virtual

Changes the direction of parametrization of <me>. The first and <br>

the last parametric values are modified. The "StartPoint"
of the initial curve becomes the "EndPoint" of the reversed
curve and the "EndPoint" of the initial curve becomes the
"StartPoint" of the reversed curve.
Example - If the trimmed curve is defined by:

  • a basis curve whose parameter range is [ 0.,1. ], and
  • the two trim values U1 (first parameter) and U2 (last parameter),
    the reversed trimmed curve is defined by:
  • the reversed basis curve, whose parameter range is still [ 0.,1. ], and
  • the two trim values 1. - U2 (first parameter)
    and 1. - U1 (last parameter).

Implements Geom2d_Curve.

Standard_Real Geom2d_TrimmedCurve::ReversedParameter ( const Standard_Real  U) const
virtual

 Returns the  parameter on the  reversed  curve for <br>
     the point of parameter U on <me>. <br>


returns UFirst + ULast - U

Implements Geom2d_Curve.

void Geom2d_TrimmedCurve::SetTrim ( const Standard_Real  U1,
const Standard_Real  U2,
const Standard_Boolean  Sense = Standard_True 
)

 Changes this trimmed curve, by redefining the <br>

parameter values U1 and U2, which limit its basis curve.
Note: If the basis curve is periodic, the trimmed curve
has the same orientation as the basis curve if Sense
is true (default value) or the opposite orientation if Sense is false.
Warning
If the basis curve is periodic, the bounds of the
trimmed curve may be different from U1 and U2 if the
parametric origin of the basis curve is within the arc
of the trimmed curve. In this case, the modified
parameter will be equal to U1 or U2 plus or minus the period.
Exceptions
Standard_ConstructionError if:

  • the basis curve is not periodic, and either U1 or U2
    are outside the bounds of the basis curve, or
  • U1 is equal to U2.
gp_Pnt2d Geom2d_TrimmedCurve::StartPoint ( ) const
virtual

Returns the start point of <me>. <br>

This point is the evaluation of the curve from the
"FirstParameter".
//! value and derivatives
Warnings :
The returned derivatives have the same orientation as the
derivatives of the basis curve.

Implements Geom2d_BoundedCurve.

void Geom2d_TrimmedCurve::Transform ( const gp_Trsf2d T)
virtual

 Applies the transformation T to this trimmed curve. <br>

Warning The basis curve is also modified.

Implements Geom2d_Geometry.

virtual Standard_Real Geom2d_TrimmedCurve::TransformedParameter ( const Standard_Real  U,
const gp_Trsf2d T 
) const
virtual

 Returns the  parameter on the  transformed  curve for <br>
     the transform of the point of parameter U on <me>. <br>


me->Transformed(T)->Value(me->TransformedParameter(U,T))

is the same point as

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

This methods calls the basis curve method.

Reimplemented from Geom2d_Curve.


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