API Docs for: 0.7.0

Lights

Extends Component
Module: lighting
Parent Module: xeogl

A Lights defines a group of light sources within a Scene.

Overview

A Lights may contain a virtually unlimited number of three types of light source:

  • AmbientLights, which are fixed-intensity and fixed-color, and affect all the Scene's Entities equally,
  • PointLights, which emit light that originates from a single point and spreads outward in all directions,
  • DirLights, which illuminate all the Entities equally from a given direction and may cast shadows, and
  • SpotLights, which eminate from a position in a given direction and may also cast shadows.

A Lights can also have two other components that define environmental reflection and irradiance:

Examples

Usage

In the example below we'll customize the default Scene's light sources, then create a metallic sphere entity.


// We're using the default xeogl Scene
// Get Scene's Lights
var lights = xeogl.scene.lights;

// Customize the light sources
lights.lights = [
   new xeogl.DirLight({
       dir: [0.8, -0.6, -0.8],
       color: [0.8, 0.8, 0.8],
       space: "view"
   }),
   new xeogl.DirLight({
       dir: [-0.8, -0.4, -0.4],
       color: [0.4, 0.4, 0.5],
       space: "view"
   }),
   new xeogl.DirLight({
       dir: [0.2, -0.8, 0.8],
       color: [0.8, 0.8, 0.8],
       space: "view"
   })
];

// Add a light cube map
lights.lightMap = new xeogl.CubeTexture({
   src: [
       "textures/light/Uffizi_Gallery/Uffizi_Gallery_Irradiance_PX.png",
       "textures/light/Uffizi_Gallery/Uffizi_Gallery_Irradiance_NX.png",
       "textures/light/Uffizi_Gallery/Uffizi_Gallery_Irradiance_PY.png",
       "textures/light/Uffizi_Gallery/Uffizi_Gallery_Irradiance_NY.png",
       "textures/light/Uffizi_Gallery/Uffizi_Gallery_Irradiance_PZ.png",
       "textures/light/Uffizi_Gallery/Uffizi_Gallery_Irradiance_NZ.png"
   ]
});

// Add a reflection cube map
lights.reflectionMap = new xeogl.CubeTexture({
   src: [
       "textures/reflect/Uffizi_Gallery/Uffizi_Gallery_Radiance_PX.png",
       "textures/reflect/Uffizi_Gallery/Uffizi_Gallery_Radiance_NX.png",
       "textures/reflect/Uffizi_Gallery/Uffizi_Gallery_Radiance_PY.png",
       "textures/reflect/Uffizi_Gallery/Uffizi_Gallery_Radiance_NY.png",
       "textures/reflect/Uffizi_Gallery/Uffizi_Gallery_Radiance_PZ.png",
       "textures/reflect/Uffizi_Gallery/Uffizi_Gallery_Radiance_NZ.png"
   ]
});

// Create a metallic sphere entity
new xeogl.Entity({
   material: new xeogl.MetallicMaterial({
       roughness: 1.0,
       metallic: 1.0,
       baseColorMap: new xeogl.Texture({
           src: "textures/materials/poligon/RustMixedOnPaint012_1k/RustMixedOnPaint012_COL_VAR1_1K.jpg"
       }),
       roughnessMap: new xeogl.Texture({
           src: "textures/materials/poligon/RustMixedOnPaint012_1k/RustMixedOnPaint012_REFL_1K.jpg"
       })
   }),
   geometry: new xeogl.SphereGeometry()
});

Constructor

Lights

(
  • [scene]
  • [cfg]
)

Parameters:

  • [scene] Scene optional

    Parent Scene - creates this Lights in the default Scene when omitted.

  • [cfg] optional

    Configs

    • [id] String optional

      Optional ID, unique among all components in the parent scene, generated automatically when omitted.

    • [meta] String:Object optional

      Optional map of user-defined metadata to attach to this Lights.

    • [lights] Array of String | Entity optional

      Array of light source IDs or instances.

    • [lightMap=undefined] CubeTexture optional

      A light map CubeTexture. Must be within the same Scene as this Lights.

    • [reflectionMap=undefined] CubeTexture optional

      A reflection map CubeTexture. Must be within the same Scene as this Lights.

Methods

create

(
  • [cfg]
)

Convenience method for creating a Component within this Component's Scene.

The method is given a component configuration, like so:

var material = myComponent.create({
     type: "xeogl.PhongMaterial",
     diffuse: [1,0,0],
     specular: [1,1,0]
}, "myMaterial");

Parameters:

  • [cfg] optional

    Configuration for the component instance.

Returns:

:

destroy

()

Destroys this component.

Fires a destroyed event on this Component.

Automatically disassociates this component from other components, causing them to fall back on any defaults that this component overrode on them.

TODO: describe effect with respect to #create

error

(
  • message
)

Logs an error for this component to the JavaScript console.

The console message will have this format: [ERROR] [<component type> =<component id>: <message>

Also fires the message as an error event on the parent Scene.

Parameters:

  • message String

    The message to log

fire

(
  • event
  • value
  • [forget=false]
)

Fires an event on this component.

Notifies existing subscribers to the event, optionally retains the event to give to any subsequent notifications on the event as they are made.

Parameters:

  • event String

    The event type name

  • value Object

    The event parameters

  • [forget=false] Boolean optional

    When true, does not retain for subsequent subscribers

hasSubs

(
  • event
)
Boolean

Returns true if there are any subscribers to the given event on this component.

Parameters:

  • event String

    The event

Returns:

Boolean:

True if there are any subscribers to the given event on this component.

isType

(
  • type
)
Boolean

Tests if this component is of the given type, or is a subclass of the given type.

The type may be given as either a string or a component constructor.

This method works by walking up the inheritance type chain, which this component provides in property superTypes, returning true as soon as one of the type strings in the chain matches the given type, of false if none match.

Examples:

var myRotate = new xeogl.Rotate({ ... });

myRotate.isType(xeogl.Component); // Returns true for all xeogl components
myRotate.isType("xeogl.Component"); // Returns true for all xeogl components
myRotate.isType(xeogl.Rotate); // Returns true
myRotate.isType(xeogl.Transform); // Returns true
myRotate.isType("xeogl.Transform"); // Returns true
myRotate.isType(xeogl.Entity); // Returns false, because xeogl.Rotate does not (even indirectly) extend xeogl.Entity

Parameters:

  • type String | Function

    Component type to compare with, eg "xeogl.PhongMaterial", or a xeogl component constructor.

Returns:

Boolean:

True if this component is of given type or is subclass of the given type.

log

(
  • message
)

Logs a console debugging message for this component.

The console message will have this format: [LOG] [<component type> <component id>: <message>

Also fires the message as a log event on the parent Scene.

Parameters:

  • message String

    The message to log

off

(
  • handle
)

Cancels an event subscription that was previously made with on or once.

Parameters:

  • handle String

    Publication handle

on

(
  • event
  • callback
  • [scope=this]
)
String

Subscribes to an event on this component.

The callback is be called with this component as scope.

Parameters:

  • event String

    The event

  • callback Function

    Called fired on the event

  • [scope=this] Object optional

    Scope for the callback

Returns:

String:

Handle to the subscription, which may be used to unsubscribe with {@link #off}.

once

(
  • event
  • callback
  • [scope=this]
)

Subscribes to the next occurrence of the given event, then un-subscribes as soon as the event is handled.

This is equivalent to calling on, and then calling off inside the callback function.

Parameters:

  • event String

    Data event to listen to

  • callback Function(data)

    Called when fresh data is available at the event

  • [scope=this] Object optional

    Scope for the callback

warn

(
  • message
)

Logs a warning for this component to the JavaScript console.

The console message will have this format: [WARN] [<component type> =<component id>: <message>

Also fires the message as a warn event on the parent Scene.

Parameters:

  • message String

    The message to log

Properties

destroyed

Boolean

True as soon as this Component has been destroyed

id

String final

Unique ID for this Component within its parent Scene.

isDefault

Boolean

Indicates whether this is one of the Scene's built-in Components.

lightMap

CubeTexture

A CubeTexture that defines the brightness of the surfaces of attached Entities.

Must be within the same Scene as this Lights.

Fires a lightMap event on change.

Default: undefined

lights

Array of AmbientLight, PointLight, DirLight or SpotLight

The light sources in this Lights.

Note that when removing or inserting light sources, you must reassign this property to the modified array, so that this Lights able to detect that lights sources were actually added or removed. For example:

var lights = myLights.lights;
                    lights.push(new xeogl.PointLight({...}));
                    myLights.lights = lights; // This way, the xeogl.Lights component is able to detect that the new light was added.
                    

We'll be able to relax this once JavaScript gets the (proper) ability to observe array updates.

Fires a lights event on change.

Default: []

metadata

Object

Arbitrary, user-defined metadata on this component.

reflectionMap

CubeTexture

A CubeTexture that defines a background image that is reflected in the surfaces of attached Entities.

Must be within the same Scene as this Lights.

Fires a reflectionMap event on change.

Default: undefined

scene

Scene final

The parent Scene that contains this Component.

superTypes

Array of String final

An array of strings that indicates the chain of super-types within this component's inheritance hierarchy.

For example, if this component is a Rotate, which extends Transform, which in turn extends Component, then this property will have the value:

["xeogl.Component", "xeogl.Transform"]
                    

Note that the chain is ordered downwards in the hierarchy, ie. from super-class down towards sub-class.

type

String final

JavaScript class name for this Component.

For example: "xeogl.AmbientLight", "xeogl.ColorTarget", "xeogl.Lights" etc.

Events

destroyed

Fired when this Component is destroyed.

lightMap

Fired whenever this Lights's lightMap property changes.

Event Payload:

  • value Object

    Number The property's new value

lights

Fired whenever this Lights's lights property changes.

Event Payload:

  • value Object

    Number The property's new value

reflectionMap

Fired whenever this Lights's reflectionMap property changes.

Event Payload:

  • value Object

    Number The property's new value