V3d_PositionalLight Class Reference

Creation and modification of an isolated (positional) light source. It is also defined by the color and two attenuation factors ConstAttentuation() and LinearAttentuation(). The resulting attenuation factor determining the illumination of a surface depends on the following formula: More...

#include <V3d_PositionalLight.hxx>

Inheritance diagram for V3d_PositionalLight:

Public Member Functions
	V3d_PositionalLight (const gp_Pnt &thePos, const Quantity_Color &theColor=Quantity_NOC_WHITE)
	Creates an isolated light source in the viewer with default attenuation factors (1.0, 0.0).
const gp_Pnt &	Position () const
	Returns location of positional/spot light; (0, 0, 0) by default.
void	Position (Standard_Real &theX, Standard_Real &theY, Standard_Real &theZ) const
	Returns location of positional/spot light.
void	SetPosition (const gp_Pnt &thePosition)
	Setup location of positional/spot light.
void	SetPosition (Standard_Real theX, Standard_Real theY, Standard_Real theZ)
	Setup location of positional/spot light.
Public Member Functions inherited from Graphic3d_CLight
	Graphic3d_CLight (Graphic3d_TypeOfLightSource theType)
	Empty constructor, which should be followed by light source properties configuration.
void	CopyFrom (const Handle< Graphic3d_CLight > &theLight)
	Copy parameters from another light source excluding source type.
Graphic3d_TypeOfLightSource	Type () const
	Returns the Type of the Light, cannot be changed after object construction.
const TCollection_AsciiString &	Name () const
	Returns light source name; empty string by default.
void	SetName (const TCollection_AsciiString &theName)
	Sets light source name.
const Quantity_Color &	Color () const
	Returns the color of the light source; WHITE by default.
void	SetColor (const Quantity_Color &theColor)
	Defines the color of a light source by giving the basic color.
Standard_Boolean	IsEnabled () const
	Check that the light source is turned on; TRUE by default. This flag affects all occurrences of light sources, where it was registered and activated; so that it is possible defining an active light in View which is actually in disabled state.
void	SetEnabled (Standard_Boolean theIsOn)
	Change enabled state of the light state. This call does not remove or deactivate light source in Views/Viewers; instead it turns it OFF so that it just have no effect.
Standard_Boolean	ToCastShadows () const
	Return TRUE if shadow casting is enabled; FALSE by default. Has no effect in Ray-Tracing rendering mode.
void	SetCastShadows (Standard_Boolean theToCast)
	Enable/disable shadow casting.
Standard_Boolean	IsHeadlight () const
	Returns true if the light is a headlight; FALSE by default. Headlight flag means that light position/direction are defined not in a World coordinate system, but relative to the camera orientation.
Standard_Boolean	Headlight () const
	Alias for IsHeadlight().
void	SetHeadlight (Standard_Boolean theValue)
	Setup headlight flag.
const gp_Pnt &	Position () const
	Returns location of positional/spot light; (0, 0, 0) by default.
void	SetPosition (const gp_Pnt &thePosition)
	Setup location of positional/spot light.
void	Position (Standard_Real &theX, Standard_Real &theY, Standard_Real &theZ) const
	Returns location of positional/spot light.
void	SetPosition (Standard_Real theX, Standard_Real theY, Standard_Real theZ)
	Setup location of positional/spot light.
Standard_ShortReal	ConstAttenuation () const
	Returns constant attenuation factor of positional/spot light source; 1.0f by default. Distance attenuation factors of reducing positional/spot light intensity depending on the distance from its position:
Standard_ShortReal	LinearAttenuation () const
	Returns linear attenuation factor of positional/spot light source; 0.0 by default. Distance attenuation factors of reducing positional/spot light intensity depending on the distance from its position:
void	Attenuation (Standard_Real &theConstAttenuation, Standard_Real &theLinearAttenuation) const
	Returns the attenuation factors.
void	SetAttenuation (Standard_ShortReal theConstAttenuation, Standard_ShortReal theLinearAttenuation)
	Defines the coefficients of attenuation; values should be >= 0.0 and their summ should not be equal to 0.
gp_Dir	Direction () const
	Returns direction of directional/spot light.
void	SetDirection (const gp_Dir &theDir)
	Sets direction of directional/spot light.
void	Direction (Standard_Real &theVx, Standard_Real &theVy, Standard_Real &theVz) const
	Returns the theVx, theVy, theVz direction of the light source.
void	SetDirection (Standard_Real theVx, Standard_Real theVy, Standard_Real theVz)
	Sets direction of directional/spot light.
const gp_Pnt &	DisplayPosition () const
	Returns location of positional/spot/directional light, which is the same as returned by Position().
void	SetDisplayPosition (const gp_Pnt &thePosition)
	Setup location of positional/spot/directional light, which is the same as SetPosition() but allows directional light source (technically having no position, but this point can be used for displaying light source presentation).
Standard_ShortReal	Angle () const
	Returns an angle in radians of the cone created by the spot; 30 degrees by default.
void	SetAngle (Standard_ShortReal theAngle)
	Angle in radians of the cone created by the spot, should be within range (0.0, M_PI).
Standard_ShortReal	Concentration () const
	Returns intensity distribution of the spot light, within [0.0, 1.0] range; 1.0 by default. This coefficient should be converted into spotlight exponent within [0.0, 128.0] range:
void	SetConcentration (Standard_ShortReal theConcentration)
	Defines the coefficient of concentration; value should be within range [0.0, 1.0].
Standard_ShortReal	Intensity () const
	Returns the intensity of light source; 1.0 by default.
void	SetIntensity (Standard_ShortReal theValue)
	Modifies the intensity of light source, which should be > 0.0.
Standard_ShortReal	Smoothness () const
	Returns the smoothness of light source (either smoothing angle for directional light or smoothing radius in case of positional light); 0.0 by default.
void	SetSmoothRadius (Standard_ShortReal theValue)
	Modifies the smoothing radius of positional/spot light; should be >= 0.0.
void	SetSmoothAngle (Standard_ShortReal theValue)
	Modifies the smoothing angle (in radians) of directional light source; should be within range [0.0, M_PI/2].
bool	HasRange () const
	Returns TRUE if maximum distance of point light source is defined.
Standard_ShortReal	Range () const
	Returns maximum distance on which point light source affects to objects and is considered during illumination calculations. 0.0 means disabling range considering at all without any distance limits. Has sense only for point light sources (positional and spot).
void	SetRange (Standard_ShortReal theValue)
	Modifies maximum distance on which point light source affects to objects and is considered during illumination calculations. Positional and spot lights are only point light sources. 0.0 means disabling range considering at all without any distance limits.
const TCollection_AsciiString &	GetId () const
const Graphic3d_Vec4 &	PackedParams () const
	Packed light parameters.
const Graphic3d_Vec4 &	PackedColor () const
	Returns the color of the light source with dummy Alpha component, which should be ignored.
const Graphic3d_Vec4 &	PackedDirectionRange () const
	Returns direction of directional/spot light and range for positional/spot light in alpha channel.
Graphic3d_Vec3	PackedDirection () const
	Returns direction of directional/spot light.
Standard_Size	Revision () const
void	DumpJson (Standard_OStream &theOStream, Standard_Integer theDepth=-1) const
	Dumps the content of me into the stream.
Public Member Functions inherited from Standard_Transient
	Standard_Transient ()
	Empty constructor.
	Standard_Transient (const Standard_Transient &)
	Copy constructor – does nothing.
Standard_Transient &	operator= (const Standard_Transient &)
	Assignment operator, needed to avoid copying reference counter.
virtual	~Standard_Transient ()
	Destructor must be virtual.
virtual const opencascade::handle< Standard_Type > &	DynamicType () const
	Returns a type descriptor about this object.
Standard_Boolean	IsInstance (const opencascade::handle< Standard_Type > &theType) const
	Returns a true value if this is an instance of Type.
Standard_Boolean	IsInstance (const Standard_CString theTypeName) const
	Returns a true value if this is an instance of TypeName.
Standard_Boolean	IsKind (const opencascade::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.
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.
Standard_Transient *	This () const
	Returns non-const pointer to this object (like const_cast). For protection against creating handle to objects allocated in stack or call from constructor, it will raise exception Standard_ProgramError if reference counter is zero.
Standard_Integer	GetRefCount () const noexcept
	Get the reference counter of this object.
void	IncrementRefCounter () noexcept
	Increments the reference counter of this object.
Standard_Integer	DecrementRefCounter () noexcept
	Decrements the reference counter of this object; returns the decremented value.
virtual void	Delete () const
	Memory deallocator for transient classes.

Additional Inherited Members
Public Types inherited from Standard_Transient
typedef void	base_type
	Returns a type descriptor about this object.
Static Public Member Functions inherited from Standard_Transient
static constexpr const char *	get_type_name ()
	Returns a type descriptor about this object.
static const opencascade::handle< Standard_Type > &	get_type_descriptor ()
	Returns type descriptor of Standard_Transient class.
Protected Member Functions inherited from V3d_PositionLight
	V3d_PositionLight (Graphic3d_TypeOfLightSource theType)
	Protected constructor.
const gp_Pnt &	Position () const
	Returns location of positional/spot light; (0, 0, 0) by default.
void	Position (Standard_Real &theX, Standard_Real &theY, Standard_Real &theZ) const
	Returns location of positional/spot light.
void	SetPosition (const gp_Pnt &thePosition)
	Setup location of positional/spot light.
void	SetPosition (Standard_Real theX, Standard_Real theY, Standard_Real theZ)
	Setup location of positional/spot light.
Protected Attributes inherited from Graphic3d_CLight
TCollection_AsciiString	myId
	resource id
TCollection_AsciiString	myName
	user given name
gp_Pnt	myPosition
	light position
Quantity_ColorRGBA	myColor
	light color
Graphic3d_Vec4	myDirection
	direction of directional/spot light
Graphic3d_Vec4	myParams
	packed light parameters
Standard_ShortReal	mySmoothness
	radius for point light or cone angle for directional light
Standard_ShortReal	myIntensity
	intensity multiplier for light
const Graphic3d_TypeOfLightSource	myType
	Graphic3d_TypeOfLightSource enumeration.
Standard_Size	myRevision
	modification counter
Standard_Boolean	myIsHeadlight
	flag to mark head light
Standard_Boolean	myIsEnabled
	enabled state
Standard_Boolean	myToCastShadows
	casting shadows is requested

Detailed Description

Creation and modification of an isolated (positional) light source. It is also defined by the color and two attenuation factors ConstAttentuation() and LinearAttentuation(). The resulting attenuation factor determining the illumination of a surface depends on the following formula:

F = 1 / (ConstAttenuation() + LinearAttenuation() * Distance)

Where Distance is the distance of the isolated source from the surface.

Constructor & Destructor Documentation

V3d_PositionalLight()

V3d_PositionalLight::V3d_PositionalLight	(	const gp_Pnt &	thePos,
		const Quantity_Color &	theColor = Quantity_NOC_WHITE
	)

Creates an isolated light source in the viewer with default attenuation factors (1.0, 0.0).

Member Function Documentation

Position() [1/2]

const gp_Pnt & Graphic3d_CLight::Position ( ) const

inline

Returns location of positional/spot light; (0, 0, 0) by default.

Position() [2/2]

void Graphic3d_CLight::Position ( Standard_Real &  theX, Standard_Real &  theY, Standard_Real &  theZ  ) const

inline

Returns location of positional/spot light.

SetPosition() [1/2]

void Graphic3d_CLight::SetPosition

(

const gp_Pnt &

thePosition

)

Setup location of positional/spot light.

SetPosition() [2/2]

void Graphic3d_CLight::SetPosition ( Standard_Real  theX, Standard_Real  theY, Standard_Real  theZ  )

inline

Setup location of positional/spot light.

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

• V3d_PositionalLight.hxx