ProjectorLight Class

Represents a light that projects a texture.

Inheritance Hierarchy

SystemObject
DigitalRune.GraphicsLight
DigitalRune.GraphicsProjectorLight

Namespace: DigitalRune.Graphics
Assembly: DigitalRune.Graphics (in DigitalRune.Graphics.dll) Version: 1.2.0.0 (1.2.1.14562)

Syntax

C++

Copy

public class ProjectorLight : Light

Public Class ProjectorLight
	Inherits Light

public ref class ProjectorLight : public Light

type ProjectorLight =  
    class
        inherit Light
    end

The ProjectorLight type exposes the following members.

Constructors

	Name	Description
	ProjectorLight	Initializes a new instance of the ProjectorLight class.
	ProjectorLight(Texture2D, Projection)	Initializes a new instance of the ProjectorLight class.

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Methods

	Name	Description
	Clone	Creates a new Light that is a clone (deep copy) of the current instance. (Inherited from Light.)
	CloneCore	Makes the instance a clone (deep copy) of the specified Light. (Overrides LightCloneCore(Light).)
	CreateInstanceCore	When implemented in a derived class, creates a new instance of the Light derived class. (Overrides LightCreateInstanceCore.)
	Equals	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetIntensity	Gets the (approximated) light intensity at the given distance. (Overrides LightGetIntensity(Single).)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)

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Properties

	Name	Description
	Attenuation	Gets or sets the attenuation exponent for the distance attenuation.
	Color	Gets or sets the RGB color of the light.
	DiffuseIntensity	Gets or sets the diffuse intensity of the light.
	HdrScale	Gets or sets the HDR scale of the light.
	Name	Gets or sets the name of the light. (Inherited from Light.)
	Projection	Gets or sets the projection.
	Shape	Gets (or sets) the shape of the light volume. (Inherited from Light.)
	SpecularIntensity	Gets or sets the specular intensity of the light.
	Texture	Gets or sets the texture.

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Remarks

A projector light is similar to a Spotlight, but is usually used to project a texture. The light emitted is shaped like a view frustum and not like a cone. And the light does not have the typical "spotlight falloff".

A Projection defines the shape of the light. Usually, a PerspectiveProjection is used, but it is also possible to use a OrthographicProjection.

Projector lights have color, intensity, position, direction and range. The ProjectorLight object defines the light properties of a projector light positioned at the origin (0, 0, 0) that shines in forward direction (0, 0, -1) - see Forward. A LightNode needs to be created to position and orient a projector light within a 3D scene.

Color, DiffuseIntensity/SpecularIntensity, HdrScale, and the light distance attenuation factor (see GetDistanceAttenuation(Single, Single, Single)) are multiplied to get the final diffuse and specular light intensities which can be used in the lighting equations.

When using a low dynamic range lighting (LDR lighting) the light intensities are

Diffuse light intensity L_diffuse = Color_RGB · DiffuseIntensity
Specular light intensity L_specular = Color_RGB · SpecularIntensity

When using a high dynamic range lighting (HDR lighting) the light intensities are

Diffuse light intensity L_diffuse = Color_RGB · DiffuseIntensity · HdrScale
Specular light intensity L_specular = Color_RGB · SpecularIntensity · HdrScale

A 2D texture (see Texture) must be assigned to the projector light. If a texture is set, the light intensity is modulated with the texture to project the texture onto the lit surroundings. By default no texture is assigned. If no texture is set, the projector light does not emit any light.

Cloning: When the ProjectorLight is cloned the Texture is not duplicated. The Texture is copied by reference.

Reference

DigitalRune.Graphics Namespace