API Docs for: 1.0.0

Entity

Extends Component
Module: entities
Parent Module: xeogl

An Entity is an object within a xeogl Scene.

Overview

See the Scene class documentation for more information on Entities.

Examples

Boundaries

Local-space

A Entity provides its Local-space boundary as a Boundary3D that encloses the Geometry positions.

var scene = new xeogl.Scene();

var geometry = new xeogl.Geometry(myScene, {
     //...
});

var entity = new xeogl.Entity(myScene, {
      geometry: myGeometry,
      transform: translate
});

// Get the Local-space Boundary3D
var localBoundary = entity.localBoundary;

// Get Local-space entity-aligned bounding box (OBB),
// which is an array of eight vertices that describes
// the box that is aligned with the Entity's Geometry
var obb = localBoundary.obb;

// Get the Local-space axis-aligned bounding box (ABB),
// which contains the extents of the boundary on each axis
var aabb = localBoundary.aabb;

// get the Local-space center of the Entity:
var center = localBoundary.center;

World-space

A Entity provides its World-space boundary as a Boundary3D that encloses the Geometry positions after transformation by the Entity's Modelling transform.

var scene = new xeogl.Scene();

var geometry = new xeogl.Geometry(myScene, {
     //...
});

var translate = new xeogl.Translate(scene, {
   xyz: [-5, 0, 0] // Translate along -X axis
});

var entity = new xeogl.Entity(myScene, {
      geometry: myGeometry,
      transform: translate
});

// Get the World-space Boundary3D
var worldBoundary = entity.worldBoundary;

// Get World-space entity-aligned bounding box (OBB),
// which is an array of eight vertices that describes
// the box that is aligned with the Entity
var obb = worldBoundary.obb;

// Get the World-space axis-aligned bounding box (ABB),
// which contains the extents of the boundary on each axis
var aabb = worldBoundary.aabb;

// get the World-space center of the Entity:
var center = worldBoundary.center;

View-space

A Entity also provides its View-space boundary as a Boundary3D that encloses the Geometry positions after their transformation by the View and Modelling transforms.

// Get the View-space Boundary3D
var viewBoundary = entity.viewBoundary;

// Get View-space entity-aligned bounding box (OBB),
// which is an array of eight vertices that describes
// the box that is aligned with the Entity
var obb = viewBoundary.obb;

// Get the View-space axis-aligned bounding box (ABB),
// which contains the extents of the boundary on each axis
var aabb = viewBoundary.aabb;

// get the View-space center of the Entity:
var center = viewBoundary.center;

View-space

A Entity also provides its Canvas-space boundary as a Boundary2D that encloses the Geometry positions after their transformation by the Modelling, View and Projection transforms.

// Get the Canvas-space Boundary2D
var canvasBoundary = entity.canvasBoundary;

// Get the Canvas-space axis-aligned bounding box (ABB),
// which contains the extents of the boundary on each axis
var aabb = canvasBoundary.aabb;

// get the Canvas-space center of the Entity:
var center = canvasBoundary.center;

Constructor

Entity

(
  • [scene]
  • [cfg]
)

Parameters:

  • [scene] Scene optional

    Parent Scene - creates this Entity within xeogl's default Xeogl/scene:property by default.

  • [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 Entity.

    • [camera] String | Camera optional

      ID or instance of a Camera to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, camera.

    • [clips] String | Clips optional

      ID or instance of a Clips to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, clips.

    • [depthBuf] String | DepthBuf optional

      ID or instance of a DepthBuf to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, depth depthBuf.

    • [visibility] String | Visibility optional

      ID or instance of a Visibility to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, visibility.

    • [cull] String | Cull optional

      ID or instance of a Cull to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, cull.

    • [modes] String | Modes optional

      ID or instance of a Modes to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, modes.

    • [geometry] String | Geometry optional

      ID or instance of a Geometry to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, geometry, which is a 2x2x2 box.

    • [layer] String | Layer optional

      ID or instance of a Layer to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, layer.

    • [lights] String | Lights optional

      ID or instance of a Lights to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, lights.

    • [material] String | Material optional

      ID or instance of a Material to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, material.

    • [morphTargets] String | MorphTargets optional

      ID or instance of a MorphTargets to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, morphTargets.

    • [stage] String | Stage optional

      ID or instance of of a Stage to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, stage.

    • [transform] String | Transform optional

      ID or instance of a modelling transform to attach to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, transform (which is an identity matrix which performs no transformation).

    • [viewport] String | Viewport optional

      ID or instance of a Viewport attached to this Entity. Must be within the same Scene as this Entity. Defaults to the parent Scene's default instance, viewport, which is automatically resizes to the canvas.

    • [loading] Boolean optional

      Flag which indicates that this Entity is freshly loaded. This will increment the Spinner processes count, and then when this Entity is first rendered, will decrement the count again.

Methods

create

(
  • [cfg]
  • [instanceId]
)

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

You would typically use this method to conveniently instantiate components that you'd want to share (ie. "instance") among your Entities.

The method is given a component type, configuration and optional instance ID, like so:

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

The first time you call this method for the given type and instanceId, this method will create the PhongMaterial, passing the given attributes to the component's constructor.

If you call this method again, specifying the same type and instanceId, the method will return the same component instance that it returned the first time, and will ignore the configuration:

var material2 = component.create(xeogl.PhongMaterial, { specular: [1,1,0] }, "myMaterial");

So in this example, our PhongMaterial will continue to have the red specular and diffuse color that we specified the first time.

Each time you call this method with the same type and instanceId, the Scene will internally increment a reference count for the component instance. You can release the shared component instance with a call to Scene/putSharedComponent:method, and once you have released it as many times as you got it, the Scene will destroy the component.

Parameters:

  • [cfg] optional

    Configuration for the component instance - only used if this is the first time you are getting the component, ignored when reusing an existing instance.

  • [instanceId] String | Number optional

    Identifies the shared component instance. Note that this is not used as the ID of the component - you can specify the component ID in the cfg parameter.

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

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

billboard

Billboard

The Billboard attached to this Entity.

When Billboard/property:active, the Billboard will keep this Entity oriented towards the viewpoint.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default billboard (an identity matrix) when set to a null or undefined value.

Fires an billboard event on change.

camera

Camera

The Camera attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default camera when set to a null or undefined value.

Fires an camera event on change.

canvasBoundary

Boundary2D final

Canvas-space 2D boundary.

This is a Boundary2D that encloses this Entity's geometry after transformation by this Entity's modelling transform and Camera view and projection transforms.

The Boundary2D will fire an updated event whenever there are any changes to the Geometry, transform or Camera that would affect its extents.

The a Boundary2D is lazy-instantiated the first time that this property is referenced. If destroy is then called on it, then this property will be assigned to a fresh Boundary2D instance next time it's referenced.

Performance

To minimize performance overhead, only reference this property if you need it, and destroy the Boundary2D as soon as you don't need it anymore.

clips

Clips

The Clips attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default clips when set to a null or undefined value.

Fires an clips event on change.

colorBuf

ColorBuf

The ColorBuf attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default colorBuf when set to a null or undefined value.

Fires an colorBuf event on change.

colorTarget

ColorTarget private

The ColorTarget attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default colorTarget when set to a null or undefined value.

Fires an colorTarget event on change.

cull

Cull

The Cull attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default cull when set to a null or undefined value.

Fires an cull event on change.

depthBuf

DepthBuf

The DepthBuf attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default depthBuf when set to a null or undefined value.

Fires an depthBuf event on change.

depthTarget

DepthTarget private

The DepthTarget attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default depthTarget when set to a null or undefined value.

Fires an depthTarget event on change.

destroyed

Boolean

True as soon as this Component has been destroyed

geometry

Geometry

The Geometry attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default camera (a simple box) when set to a null or undefined value.

Fires an Entity/geometry:event event on change.

Updates Entity/boundary, Entity/worldObb and Entity/center

glsl

JSON final

JSON object containing the (GLSL) source code of the shaders for this Entity.

This is sometimes useful to have as a reference when constructing your own custom Shader components.

Will return null if xeogl has not yet rendered this Entity.

glslString

String final

The (GLSL) source code of the shaders for this Entity, as a string.

This is sometimes useful to have as a reference when constructing your own custom Shader components.

Will return null if xeogl has not yet rendered this Entity.

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.

json

JSON final

JSON object containing the state of this Component.

layer

Layer

The Layer attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default layer when set to a null or undefined value.

Fires an layer event on change.

lights

Lights

The Lights attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default lights when set to a null or undefined value.

Fires an lights event on change.

localBoundary

Boundary3D final

Local-space 3D boundary of this Entity.

This is a Boundary3D that encloses the Geometry that is attached to this Entity.

The Boundary3D will fire an updated event whenever this Entity's geometry is linked to a new Geometry, or whenever the Geometry's positions are updated.

The a Boundary3D is lazy-instantiated the first time that this property is referenced. If destroy is then called on it, then this property will be assigned to a fresh Boundary3D instance next time it's referenced.

material

Material

The Material attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default material when set to a null or undefined value.

Fires an material event on change.

metadata

Object

Arbitrary, user-defined metadata on this component.

modes

Modes

The Modes attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default modes when set to a null or undefined value.

Fires an modes event on change.

morphTargets

MorphTargets private

The MorphTargets attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default morphTargets when set to a null or undefined value.

Fires an morphTargets event on change.

scene

Scene final

The parent Scene that contains this Component.

shader

Shader private

The Shader attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default shader when set to a null or undefined value.

Fires an shader event on change.

shaderParams

ShaderParams private

The ShaderParams attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default shaderParams when set to a null or undefined value.

Fires an shaderParams event on change.

stage

Stage

The Stage attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default stage when set to a null or undefined value.

Fires an stage event on change.

stationary

Stationary

The Stationary attached to this Entity.

When Stationary/property:active, the Stationary will prevent the translation component of the viewing transform from being applied to this Entity, yet still allowing it to rotate.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default stationary, which is disabled by default.

Fires an stationary event on change.

string

String final

Inherited from Component but overwritten in src/component.js:1058

String containing the serialized JSON state of 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.

transform

Transform

The Local-to-World-space (modelling) Transform attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default transform (an identity matrix) when set to a null or undefined value.

Fires an transform event on change.

Updates Entity/boundary, Entity/worldObb and Entity/center

type

String final

JavaScript class name for this Component.

This is used when loading Scenes from JSON, and is included in the JSON representation of this Component, so that this class may be instantiated when loading it from the JSON representation.

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

viewBoundary

Boundary3D final

View-space 3D boundary of this Entity.

This is a Boundary3D that encloses the Geometry that is attached to this Entity after transformation by this Entity's modelling transform and Camera view transform.

The Boundary3D will fire an updated event whenever there are any changes to the Geometry, transform or Camera that would affect its extents.

The a Boundary3D is lazy-instantiated the first time that this property is referenced. If destroy is then called on it, then this property will be assigned to a fresh Boundary3D instance next time it's referenced.

Performance

To minimize performance overhead, only reference this property if you need it, and destroy the Boundary3D as soon as you don't need it anymore.

viewport

Viewport

The Viewport attached to this Entity.

Must be within the same Scene as this Entity. When set to a null or undefined value, defaults to the parent Scene's default viewport, which automatically resizes to the canvas.

Fires an viewport event on change.

visibility

Visibility

The Visibility attached to this Entity.

Must be within the same Scene as this Entity. Defaults to the parent Scene's default visibility when set to a null or undefined value.

Fires an visibility event on change.

worldBoundary

Boundary3D final

World-space 3D boundary of this Entity.

This is a Boundary3D that encloses the Geometry that is attached to this Entity after transformation by this Entity's modelling transform.

The Boundary3D will fire an updated event whenever this Entity's geometry is linked to a new Geometry, or whenever the Geometry's positions are updated.

The a Boundary3D is lazy-instantiated the first time that this property is referenced. If destroy is then called on it, then this property will be assigned to a fresh Boundary3D instance next time it's referenced.

Example

here

Performance

To minimize performance overhead, only reference this property if you need it, and destroy the Boundary3D as soon as you don't need it anymore.

Events

billboard

Fired whenever this Entity's billboard property changes.

Event Payload:

  • value Object

    The property's new value

camera

Fired whenever this Entity's camera property changes.

Event Payload:

  • value Object

    The property's new value

clips

Fired whenever this Entity's clips property changes.

Event Payload:

  • value Object

    The property's new value

colorBuf

Fired whenever this Entity's colorBuf property changes.

Event Payload:

  • value Object

    The property's new value

colorTarget

Fired whenever this Entity's colorTarget property changes.

Event Payload:

  • value Object

    The property's new value

cull

Fired whenever this Entity's cull property changes.

Event Payload:

  • value Object

    The property's new value

depthBuf

Fired whenever this Entity's depthBuf property changes.

Event Payload:

  • value Object

    The property's new value

depthTarget

Fired whenever this Entity's depthTarget property changes.

Event Payload:

  • value Object

    The property's new value

destroyed

Fired when this Component is destroyed.

layer

Fired whenever this Entity's layer property changes.

Event Payload:

  • value Object

    The property's new value

lights

Fired whenever this Entity's lights property changes.

Event Payload:

  • value Object

    The property's new value

material

Fired whenever this Entity's material property changes.

Event Payload:

  • value Object

    The property's new value

modes

Fired whenever this Entity's geometry property changes.

Event Payload:

  • value Object

    The property's new value

modes

Fired whenever this Entity's modes property changes.

Event Payload:

  • value Object

    The property's new value

morphTargets

Fired whenever this Entity's morphTargets property changes.

Event Payload:

  • value Object

    The property's new value

picked

Fired when this Entity is picked via a call to the Canvas/pick:method method on the parent Scene's Canvas.

Event Payload:

  • entityId String

    The ID of this Entity.

  • canvasX Number

    The X-axis Canvas coordinate that was picked.

  • canvasY Number

    The Y-axis Canvas coordinate that was picked.

shader

Fired whenever this Entity's shader property changes.

Event Payload:

  • value Object

    The property's new value

shaderParams

Fired whenever this Entity's shaderParams property changes.

Event Payload:

  • value Object

    The property's new value

stage

Fired whenever this Entity's stage property changes.

Event Payload:

  • value Object

    The property's new value

stationary

Fired whenever this Entity's stationary property changes.

Event Payload:

  • value Object

    The property's new value

transform

Fired whenever this Entity's transform property changes.

Event Payload:

  • value Object

    The property's new value

viewport

Fired whenever this Entity's viewport property changes.

Event Payload:

  • value Object

    The property's new value

visibility

Fired whenever this Entity's visibility property changes.

Event Payload:

  • value Object

    The property's new value