de.grogra.ray.physics
Interface Light

All Superinterfaces:

Emitter, Scattering

All Known Subinterfaces:

Light

All Known Implementing Classes:

AmbientLight, DirectionalLight, LightBase, Parallelogram, PhysicalLight, PointLight, Sky, SpectralLight, SpotLight, SunSkyLight, SunSkyToDirectionalLightWrapper

public interface Light
extends Emitter

A Light instance represents a light source. The interface specializes the common methods of the Emitter interface for light sources.

Author:

Ole Kniemeyer

Field Summary

static int	AMBIENT This return value for getLightType() indicates an ambient light.
static int	AREA This return value for getLightType() indicates an area light.
static int	DIRECTIONAL This return value for getLightType() indicates a directional light.
static int	NO_LIGHT This return value for getLightType() indicates that this light should actually be ignored.
static int	POINT This return value for getLightType() indicates a point light, i.e., a light source whose rays emanate from a single point.
static int	SKY This return value for getLightType() indicates a sky light.

Fields inherited from interface de.grogra.ray.physics.Scattering

DELTA_FACTOR, IS_NON_OPAQUE, MIN_UNUSED_FLAG, NEEDS_NORMAL, NEEDS_POINT, NEEDS_TANGENTS, NEEDS_TRANSFORMATION, NEEDS_UV, RANDOM_RAYS_GENERATE_ORIGINS

Method Summary

int	getLightType() Determines the type of light source which is represented by this light.
double	getTotalPower(Environment env) Computes the total power of this light source which is emitted to the region defined by env.bounds.
boolean	isIgnoredWhenHit() Determines whether the light source shall be ignored when a shot ray happens to hit the geometry of the light source.
boolean	isShadowless() Determines whether the light source casts shadows or not.

Methods inherited from interface de.grogra.ray.physics.Emitter

completeRay, computeExitance, generateRandomOrigins

Methods inherited from interface de.grogra.ray.physics.Scattering

computeBSDF, generateRandomRays, getAverageColor, getFlags

Field Detail

AMBIENT

static final int AMBIENT

This return value for getLightType() indicates an ambient light. Ambient lights have no physically plausible counterpart in the real world and, thus, should not be considered in physically based rendering at all.

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Constant Field Values

AREA

static final int AREA

This return value for getLightType() indicates an area light.

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Constant Field Values

DIRECTIONAL

static final int DIRECTIONAL

This return value for getLightType() indicates a directional light.

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Constant Field Values

NO_LIGHT

static final int NO_LIGHT

This return value for getLightType() indicates that this light should actually be ignored.

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Constant Field Values

POINT

static final int POINT

This return value for getLightType() indicates a point light, i.e., a light source whose rays emanate from a single point. This includes the usual point lights which radiate equally in all directions, but also more general lights with a direction-dependent radiant intensity, e.g., spot lights.

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Constant Field Values

SKY

static final int SKY

This return value for getLightType() indicates a sky light.

See Also:

Constant Field Values

Method Detail

getLightType

int getLightType()

Determines the type of light source which is represented by this light.

Returns:

one of NO_LIGHT, POINT, AREA, DIRECTIONAL, SKY, AMBIENT.

getTotalPower

double getTotalPower(Environment env)

Computes the total power of this light source which is emitted to the region defined by env.bounds. Note that the computed value is not necessarily exact: It should be used just as a hint, e.g., when one of a set of lights has to be chosen randomly on the basis of their relative power.

Parameters:

env - environment which defines the bounds of the scene

Returns:

total power emitted to the region env.bounds

isIgnoredWhenHit

boolean isIgnoredWhenHit()

Determines whether the light source shall be ignored when a shot ray happens to hit the geometry of the light source.

Returns:

true iff the light source shall be ignored

isShadowless

boolean isShadowless()

Determines whether the light source casts shadows or not.

Returns:

true iff the light source does not cast shadows