A framework to define 3D projectors.
Projector provides services for projecting points from
world-coordinates to a viewing plane. Projection could be defined by
corresponding transformation, or coordinate system. The transformation
could be constructed for a view with transposed view transformation
matrix ( that represents view-orientation ), including, for perspective
view, focal distance ( distance from an eye to the view plane ) and
translational part that represents translation of focal point in
view-coordinate space. The Select3D_Projector class recognizes the
predefined set of popular projections: axonometric, top view, front
view and uses more efficient algorithm for projection computations.
User-defined transformation could be also defined in constructor.
Perspective projection consists of two separate parts, that are
composed together during computation: transformation component and
focale distance.
More...

#include <Select3D_Projector.hxx>

Inheritance diagram for Select3D_Projector:

[legend]

Public Member Functions
	Select3D_Projector (const Handle< V3d_View > &aView)
	Constructs the 3D projector object defined by the 3D view aView. More...

	Select3D_Projector ()

	Select3D_Projector (const gp_Ax2 &CS)
	Creates an axonometric projector. <CS> represents viewing coordinate <br> system and could be constructed from x direction, view plane normal direction, and view point location in world-coordinate space. More...

	Select3D_Projector (const gp_Ax2 &CS, const Standard_Real Focus)
	Creates a perspective projector. <CS> represents viewing <br> coordinate system and could be constructed from x direction, view plane normal direction, and focal point location in world-coordinate space. <Focus> should represent distance of an eye from view plane in world-coordinate space (focal distance). More...

	Select3D_Projector (const gp_Trsf &T, const Standard_Boolean Persp, const Standard_Real Focus)
	build a Projector from the given transformation. <br> In case, when <T> transformation should represent custom view projection, it could be constructed from two separate components: transposed view orientation matrix and translation of focal point in view-coordiante system. <T> could be built up from x direction, up direction, view plane normal direction vectors and translation with SetValues(...) method, where first row arguments (a11, a12, a13, a14) are x, y, z component of x direction vector, and x value of reversed translation vector. Second row arguments, are x y z for up direction and y value of reversed translation, and the third row defined in the same manner. This also suits for simple perspective view, where <Focus> is the focale distance of an eye from view plane in world-space coordiantes. Note, that in that case amount of perspective distortion (perspective angle) should be defined through focal distance. More...

	Select3D_Projector (const gp_GTrsf &GT, const Standard_Boolean Persp, const Standard_Real Focus)
	build a Projector from the given transformation. <br> In case, when <GT> transformation should represent custom view projection, it could be constructed from two separate components: transposed view orientation matrix and translation of a focal point in view-coordinate system. This also suits for perspective view, with <Focus> that could be equal to distance from an eye to a view plane in world-coordinates (focal distance). The 3x3 transformation matrix is built up from three vectors: x direction, up direction and view plane normal vectors, where each vector is a matrix row. Then <GT> is constructed from matrix and reversed translation with methods SetTranslationPart(..) and SetVectorialPart(..). Note, that in that case amount of perspective distortion (perspective angle) should be defined through focal distance. More...

void	Set (const gp_Trsf &T, const Standard_Boolean Persp, const Standard_Real Focus)

void	SetView (const Handle< V3d_View > &V)
	Sets the 3D view V used at the time of construction. More...

const Handle_V3d_View &	View () const
	Returns the 3D view used at the time of construction. More...

virtual void	Scaled (const Standard_Boolean On=Standard_False)
	to compute with the given scale and translation. More...

virtual Standard_Boolean	Perspective () const
	Returns True if there is a perspective transformation. More...

virtual const gp_GTrsf &	Transformation () const
	Returns the active transformation. More...

virtual const gp_GTrsf &	InvertedTransformation () const
	Returns the active inverted transformation. More...

virtual const gp_Trsf &	FullTransformation () const
	Returns the original transformation. More...

virtual Standard_Real	Focus () const
	Returns the focal length. More...

virtual void	Transform (gp_Vec &D) const

virtual void	Transform (gp_Pnt &Pnt) const

virtual void	Project (const gp_Pnt &P, gp_Pnt2d &Pout) const
	Transform and apply perspective if needed. More...

void	Project (const gp_Pnt &P, Standard_Real &X, Standard_Real &Y, Standard_Real &Z) const
	Transform and apply perspective if needed. More...

virtual void	Project (const gp_Pnt &P, const gp_Vec &D1, gp_Pnt2d &Pout, gp_Vec2d &D1out) const
	Transform and apply perspective if needed. More...

virtual gp_Lin	Shoot (const Standard_Real X, const Standard_Real Y) const
	return a line going through the eye towards the 2d point <X,Y>. More...

virtual void	Transform (gp_Pnt &P, const gp_GTrsf &T) const

virtual void	Transform (gp_Lin &D, const gp_GTrsf &T) const

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	Delete () const
	Memory deallocator for transient classes. 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...

Protected Attributes
Standard_Boolean	myPersp

Standard_Real	myFocus

gp_Trsf	myScaledTrsf

gp_GTrsf	myGTrsf

gp_GTrsf	myInvTrsf

Detailed Description

A framework to define 3D projectors.
Projector provides services for projecting points from
world-coordinates to a viewing plane. Projection could be defined by
corresponding transformation, or coordinate system. The transformation
could be constructed for a view with transposed view transformation
matrix ( that represents view-orientation ), including, for perspective
view, focal distance ( distance from an eye to the view plane ) and
translational part that represents translation of focal point in
view-coordinate space. The Select3D_Projector class recognizes the
predefined set of popular projections: axonometric, top view, front
view and uses more efficient algorithm for projection computations.
User-defined transformation could be also defined in constructor.
Perspective projection consists of two separate parts, that are
composed together during computation: transformation component and
focale distance.

Constructor & Destructor Documentation

Select3D_Projector::Select3D_Projector ( const Handle< V3d_View > & aView )

Constructs the 3D projector object defined by the 3D view aView.

Select3D_Projector::Select3D_Projector ( )

Select3D_Projector::Select3D_Projector ( const gp_Ax2 & CS )

 Creates an axonometric projector. <CS> represents viewing coordinate <br>

system and could be constructed from x direction, view plane normal direction,
and view point location in world-coordinate space.

Select3D_Projector::Select3D_Projector	(	const gp_Ax2 &	CS,
		const Standard_Real	Focus
	)

 Creates  a  perspective  projector. <CS> represents viewing <br>

coordinate system and could be constructed from x direction,
view plane normal direction, and focal point location in world-coordinate
space. <Focus> should represent distance of an eye from view plane
in world-coordinate space (focal distance).

Select3D_Projector::Select3D_Projector	(	const gp_Trsf &	T,
		const Standard_Boolean	Persp,
		const Standard_Real	Focus
	)

 build a Projector from the given transformation. <br>

In case, when <T> transformation should represent custom view projection,
it could be constructed from two separate components: transposed view
orientation matrix and translation of focal point in view-coordiante
system. <T> could be built up from x direction, up direction,
view plane normal direction vectors and translation with SetValues(...)
method, where first row arguments (a11, a12, a13, a14) are x, y, z
component of x direction vector, and x value of reversed translation
vector. Second row arguments, are x y z for up direction and y value of
reversed translation, and the third row defined in the same manner.
This also suits for simple perspective view, where <Focus> is the focale
distance of an eye from view plane in world-space coordiantes.
Note, that in that case amount of perspective distortion (perspective
angle) should be defined through focal distance.

Select3D_Projector::Select3D_Projector	(	const gp_GTrsf &	GT,
		const Standard_Boolean	Persp,
		const Standard_Real	Focus
	)

 build a Projector from the given transformation. <br>

In case, when <GT> transformation should represent custom view
projection, it could be constructed from two separate components:
transposed view orientation matrix and translation of a focal point
in view-coordinate system.
This also suits for perspective view, with <Focus> that could be
equal to distance from an eye to a view plane in
world-coordinates (focal distance).
The 3x3 transformation matrix is built up from three vectors:
x direction, up direction and view plane normal vectors, where each
vector is a matrix row. Then <GT> is constructed from matrix and
reversed translation with methods SetTranslationPart(..) and
SetVectorialPart(..).
Note, that in that case amount of perspective distortion (perspective
angle) should be defined through focal distance.

Member Function Documentation

virtual Standard_Real Select3D_Projector::Focus ( ) const

virtual

Returns the focal length.

virtual const gp_Trsf& Select3D_Projector::FullTransformation ( ) const

virtual

Returns the original transformation.

virtual const gp_GTrsf& Select3D_Projector::InvertedTransformation ( ) const

virtual

Returns the active inverted transformation.

virtual Standard_Boolean Select3D_Projector::Perspective ( ) const

virtual

Returns True if there is a perspective transformation.

virtual void Select3D_Projector::Project	(	const gp_Pnt &	P,
		gp_Pnt2d &	Pout
	)		const

virtual

Transform and apply perspective if needed.

void Select3D_Projector::Project	(	const gp_Pnt &	P,
		Standard_Real &	X,
		Standard_Real &	Y,
		Standard_Real &	Z
	)		const

Transform and apply perspective if needed.

virtual void Select3D_Projector::Project	(	const gp_Pnt &	P,
		const gp_Vec &	D1,
		gp_Pnt2d &	Pout,
		gp_Vec2d &	D1out
	)		const

virtual

Transform and apply perspective if needed.

virtual void Select3D_Projector::Scaled ( const Standard_Boolean On = Standard_False )

virtual

to compute with the given scale and translation.

void Select3D_Projector::Set	(	const gp_Trsf &	T,
		const Standard_Boolean	Persp,
		const Standard_Real	Focus
	)

void Select3D_Projector::SetView ( const Handle< V3d_View > & V )

Sets the 3D view V used at the time of construction.

virtual gp_Lin Select3D_Projector::Shoot	(	const Standard_Real	X,
		const Standard_Real	Y
	)		const

virtual

return a line going through the eye towards the
2d point <X,Y>.

virtual void Select3D_Projector::Transform ( gp_Vec & D ) const

virtual

virtual void Select3D_Projector::Transform ( gp_Pnt & Pnt ) const

virtual

virtual void Select3D_Projector::Transform	(	gp_Pnt &	P,
		const gp_GTrsf &	T
	)		const

virtual

virtual void Select3D_Projector::Transform	(	gp_Lin &	D,
		const gp_GTrsf &	T
	)		const

virtual

virtual const gp_GTrsf& Select3D_Projector::Transformation ( ) const

virtual

Returns the active transformation.

const Handle_V3d_View& Select3D_Projector::View ( ) const

Returns the 3D view used at the time of construction.

Field Documentation

Standard_Real Select3D_Projector::myFocus

protected

gp_GTrsf Select3D_Projector::myGTrsf

protected

gp_GTrsf Select3D_Projector::myInvTrsf

protected

Standard_Boolean Select3D_Projector::myPersp

protected

gp_Trsf Select3D_Projector::myScaledTrsf

protected

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

Select3D_Projector.hxx

Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Field Documentation