DD::Image::LightOp Class Reference

LightOp defines a 3D light. More...

Inherits DD::Image::CameraOp.

List of all members.

Public Types
enum	{ eNoFalloff, eLinearFalloff, eQuadraticFalloff, eCubicFalloff }
enum	LightType { ePointLight, eDirectionalLight, eSpotLight, eOtherLight }
Public Member Functions
	LightOp (Node *node)
int	samples () const
void	set_samples (int n)
float	sample_width () const
void	set_sample_width (float width)
const Pixel &	color () const
void	color (const Pixel &v)
float	intensity () const
void	set_intensity (float v)
bool	falloff () const
void	set_falloff (bool b)
int	falloffType () const
void	set_falloffType (int b)
bool	cast_shadows () const
void	set_cast_shadows (bool b)
float	depthmap_bias () const
void	set_depthmap_bias (float v)
float	shadow_jitter_scale () const
void	set_shadow_jitter_scale (float v)
int	depthmap_width () const
void	set_depthmap_width (int n)
void	setShadowMaskChannel (Channel &channel)
Channel	getShadowMaskChannel ()
virtual bool	is_delta_light () const
virtual void	get_L_vector (LightContext &ltx, const Vector3 &P, const Vector3 &N, Vector3 &L, float &D) const
virtual float	get_shadowing (const LightContext &ltx, const Vector3 &P, Pixel &out)
virtual void	get_color (LightContext &ltx, const Vector3 &P, const Vector3 &N, const Vector3 &L, float D, Pixel &out)
virtual double	hfov () const
virtual double	vfov () const
virtual double	aspect () const
virtual int	lightType () const
void	_validate (bool for_real)
virtual void	request (ChannelMask, int count)
void	knobs (Knob_Callback)
void	color_knobs (Knob_Callback)
void	attenuation_knobs (Knob_Callback)
void	shadow_knobs (Knob_Callback)
unsigned	node_color () const
void	build_handles (ViewerContext *)
void	draw_handle (ViewerContext *)
virtual void	shade_GL (ViewerContext *, int light_num)
const char *	node_help () const
	This is the light node help.
const char *	displayName () const
	This is the node display name.
const char *	Class () const
Static Public Attributes
static const Description	description
Protected Attributes
Pixel	color_
	Color of the light (can be >3 channels!).
float	intensity_
	Global intensity.
bool	falloff_
	Whether to factor in physical falloff.
int	falloffType_
	falloff type
int	samples_
	The number of samples (for area testing).
float	sample_width_
	sample width (for shadowing)
bool	cast_shadows_
	Whether light casts shadows.
float	depthmap_bias_
	Offset in Z of shadow buffer.
float	shadow_jitter_scale_
	Size of shadow jitter.
int	depthmap_width_
	Size in pixels of shadow buffer.
Channel	_shadowMaskChannel
	Output the shadow mask to this channel.

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Detailed Description

LightOp defines a 3D light.

Light base class which defaults to point source lighting with falloff.

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Member Function Documentation

bool LightOp::is_delta_light

(

)

const [virtual]

Whether the light has a delta distribution (point/spot/direct lights)

Whether the light has a delta distribution (point/spot/direct lights).

Referenced by DD::Image::Iop::fragment_shader().

void LightOp::get_L_vector	(	LightContext &	ltx,
		const Vector3 &	P,
		const Vector3 &	N,
		Vector3 &	L,
		float &	D
	)			const [virtual]

Calculate direction vector and distance from this light to P.

Calculate a normalized direction vector L and distance D to surface point P. Surface normal N is passed to allow lights like area lights to simulate a large emission surface.

References DD::Image::Vector3::fast_normalize(), DD::Image::Vector3::normalize(), and DD::Image::LightContext::p().

Referenced by DD::Image::Iop::fragment_shader().

float LightOp::get_shadowing	(	const LightContext &	ltx,
		const Vector3 &	P,
		Pixel &	out
	)			[virtual]

Return the amount of shadowing the light creates at surface point P. and optionally copies the shadow mask to the output pixel

Project surface point P into light's view aperture and test if it's further in Z than the shadow buffer sample. Jittered multi- sampling of the shadow buffer is supported when samples is greater than 1 which produces soft edged shadows.

References _shadowMaskChannel, DD::Image::Op::aborted(), cast_shadows_, clamp(), DD::Image::LightContext::depthmap(), depthmap_bias_, fast_floor(), DD::Image::LightContext::matrix(), shadow_jitter_scale_, DD::Image::Matrix4::transform(), DD::Image::Vector4::w, DD::Image::Vector4::x, DD::Image::Vector4::y, and DD::Image::Vector4::z.

Referenced by DD::Image::Iop::fragment_shader().

void LightOp::get_color	(	LightContext &	ltx,
		const Vector3 &	P,
		const Vector3 &	N,
		const Vector3 &	L,
		float	D,
		Pixel &	out
	)			[virtual]

Return the color of this light. The light vector and distance are passed.

Returns the color of the light (possibly) using the current surface point and normal to calculate attenuation and penumbra. The base class returns a point source attenuated by the inverse squared distance.

References DD::Image::Pixel::channels, color_, falloffType_, and intensity_.

Referenced by DD::Image::Iop::fragment_shader().

virtual double DD::Image::LightOp::hfov

(

)

const [inline, virtual]

field-of-view methods.

Referenced by _validate().

void LightOp::_validate

(

bool

for_real

)

[virtual]

Reimplemented from DD::Image::CameraOp.

References depthmap_width_, hfov(), DD::Image::CameraOp::LENS_ORTHOGRAPHIC, DD::Image::CameraOp::LENS_PERSPECTIVE, MAX(), MIN(), and samples_.

void LightOp::request	(	ChannelMask	channels,
		int	count
	)			[virtual]

Handle channel requests. Base class does nothing, but Lights that read imagery such as environment maps will need to implement this.

Referenced by DD::Image::Scene::request().

void LightOp::knobs

(

Knob_Callback

f

)

[virtual]

Reimplemented from DD::Image::CameraOp.

References DD::Image::Divider(), DD::Image::Newline(), and DD::Image::Tab_knob().

void LightOp::draw_handle

(

ViewerContext *

ctx

)

[virtual]

Draws a picture of a point light.

Reimplemented from DD::Image::CameraOp.

References DD::Image::Matrix4::array(), color_, DD::Image::ViewerContext::draw_knobs(), DD::Image::ViewerContext::fg_color(), DD::Image::gl_sphere(), DD::Image::gl_text(), DD::Image::glColor(), DD::Image::ViewerContext::icon_size(), DD::Image::ViewerContext::modelmatrix, DD::Image::ViewerContext::node_color(), DD::Image::Op::node_disabled(), DD::Image::Op::node_selected(), and DD::Image::Op::print_name().

void LightOp::shade_GL	(	ViewerContext *	ctx,
		int	light_num
	)			[virtual]

Point light OpenGL settings.

References DD::Image::Matrix4::a03, DD::Image::Matrix4::a13, DD::Image::Matrix4::a23, DD::Image::Vector4::array(), color_, falloffType_, intensity_, DD::Image::Op::node_disabled(), DD::Image::Vector4::set(), and DD::Image::Vector4::w.

const char * LightOp::node_help

(

)

const [virtual]

This is the light node help.

This is the light node help.

Reimplemented from DD::Image::CameraOp.

const char * LightOp::displayName

(

)

const [virtual]

This is the node display name.

This is the node display name

Reimplemented from DD::Image::Op.

References Class(), and DD::Image::Op::Description::name.

const char * LightOp::Class

(

)

const [virtual]

Reimplemented from DD::Image::CameraOp.

References DD::Image::Op::Description::name.

Referenced by displayName().