API Docs for: 0.7.0

EmphasisMaterial

Extends Material
Module: materials
Parent Module: xeogl

An EmphasisMaterial is a Material that defines the appearance of attached Entities when they are highlighted, selected or ghosted.

Examples

Example 1: Ghost effect Example 2: Ghost and highlight effects for architecture Example 3: Ghost and highlight effects for CAD Example 4: Ghost effect for CAD

Overview

  • Ghost an Entity by setting its Entity/ghost:property property true.
  • When ghosted, an Entity's appearance is controlled by its EmphasisMaterial.
  • An EmphasisMaterial provides several preset configurations that you can set it to. Select a preset by setting preset to the preset's ID. A map of available presets is provided in xeogl.EmphasisMaterial.presets.
  • By default, an Entity uses the Scene's global EmphasisMaterials, but you can give each Entity its own EmphasisMaterial when you want to customize the effect per-Entity.
  • Ghost all Entities in a Model by setting the Model's Model/ghost:property property true. Note that all Entities in a Model have the Scene's global EmphasisMaterial by default.
  • Modify the Scene's global EmphasisMaterial to customize it.

Usage

Ghosting

In the usage example below, we'll create an Entity with a ghost effect applied to it. The Entity gets its own EmphasisMaterial for ghosting, and has its Entity/ghost:property property set true to activate the effect.

var entity = new xeogl.Entity({
   geometry: new xeogl.TeapotGeometry({
       ghostEdgeThreshold: 1
   }),
   material: new xeogl.PhongMaterial({
       diffuse: [0.2, 0.2, 1.0]
   }),
   ghostMaterial: new xeogl.EmphasisMaterial({
       edges: true,
       edgeColor: [0.2, 1.0, 0.2],
       edgeAlpha: 1.0,
       edgeWidth: 2,
       vertices: true,
       vertexColor: [0.6, 1.0, 0.6],
       vertexAlpha: 1.0,
       vertexSize: 8,
       fill: true,
       fillColor: [0, 0, 0],
       fillAlpha: 0.7
   }),
   ghost: true
});

Note the ghostEdgeThreshold configuration on the Geometry we've created for our Entity. Our EmphasisMaterial is configured to draw a wireframe representation of the Geometry, which will have inner edges (ie. edges between adjacent co-planar triangles) removed for visual clarity. The ghostEdgeThreshold configuration indicates that, for this particular Geometry, an inner edge is one where the angle between the surface normals of adjacent triangles is not greater than 5 degrees. That's set to 2 by default, but we can override it to tweak the effect as needed for particular Geometries.

Here's the example again, this time using the Scene's global EmphasisMaterial by default. We'll also modify that EmphasisMaterial to customize the effect.

var entity = new xeogl.Entity({
   geometry: new xeogl.TeapotGeometry({
       ghostEdgeThreshold: 5
   }),
   material: new xeogl.PhongMaterial({
       diffuse: [0.2, 0.2, 1.0]
   }),
   ghost: true
});

var ghostMaterial = entity.scene.ghostMaterial;

ghostMaterial.edges = true;
ghostMaterial.edgeColor = [0.2, 1.0, 0.2];
ghostMaterial.edgeAlpha = 1.0;
ghostMaterial.edgeWidth = 2;
ghostMaterial.vertices = true;
ghostMaterial.vertexColor = [0.6, 1.0, 0.6];
ghostMaterial.vertexAlpha = 1.0;
ghostMaterial.vertexSize = 8;
ghostMaterial.fill = true;
ghostMaterial.fillColor = [0, 0, 0];
ghostMaterial.fillAlpha = 0.7;

Highlighting

In the next example, we'll use a ghosting in conjunction with highlighting, to emphasise a couple of objects within a gearbox Model. We'll load the Model from glTF, then ghost all of its Entities except for two gears, which we'll highlight instead. The ghosted Entities have the Scene's global ghosting EmphasisMaterial, which we'll modify. The highlighted Entities also have the Scene's global highlighting EmphasisMaterial, which we'll modify as well.

var model = new xeogl.GLTFModel({
    src: "models/gltf/gearbox_conical/scene.gltf",
    ghostEdgeThreshold: 10
});

model.on("loaded", function() {

   model.ghost = true;

   model.entities["gearbox#77.0"].ghost = false;
   model.entities["gearbox#79.0"].ghost = false;

   model.entities["gearbox#77.0"].highlight = true;
   model.entities["gearbox#79.0"].highlight = true;

   var ghostMaterial = model.scene.ghostMaterial;

   ghostMaterial.edges = true;
   ghostMaterial.edgeColor = [0.4, 0.4, 1.6];
   ghostMaterial.edgeAlpha = 0.8;
   ghostMaterial.edgeWidth = 3;
   ghostMaterial.vertices = false;
   ghostMaterial.vertexColor = [0.7, 1.0, 0.7];
   ghostMaterial.vertexAlpha = 0.9;
   ghostMaterial.vertexSize = 4.0;
   ghostMaterial.fill = true;
   ghostMaterial.fillColor = [0.2, 0.2, 0.7];
   ghostMaterial.fillAlpha = 0.9;

   var highlightMaterial = model.scene.highlightMaterial;

   highlightMaterial.color = [1.0, 1.0, 1.0];
   highlightMaterial.alpha = 1.0;
});

Presets

For convenience, an EmphasisMaterial provides several preset configurations that you can set it to, which are provided in xeogl.EmphasisMaterial.presets:

var presets = xeogl.EmphasisMaterial.presets;

The presets look something like this:

{
       "default": {
           edges: true,
           edgeColor: [0.2, 0.2, 0.2],
           edgeAlpha: 0.5,
           edgeWidth: 1,
           vertices: false,
           vertexColor: [0.4, 0.4, 0.4],
           vertexAlpha: 0.7,
           vertexSize: 4.0,
           fill: true,
           fillColor: [0.4, 0.4, 0.4],
           fillAlpha: 0.2
       },

        "sepia": {
           edges: true,
           edgeColor: [0.52, 0.45, 0.41],
           edgeAlpha: 1.0,
           edgeWidth: 1,
           vertices: false,
           vertexColor: [0.7, 1.0, 0.7],
           vertexAlpha: 0.9,
           vertexSize: 4.0,
           fill: true,
           fillColor: [0.97, 0.79, 0.66],
           fillAlpha: 0.4
       },

       //...
}

Let's switch the Scene's global default EmphasisMaterial over to the "sepia" preset used in Example 4: Ghost effect for CAD.

scene.ghostMaterial.preset = "sepia";

You can also just create an EmphasisMaterial from a preset:

var entity = new xeogl.Entity({
   geometry: new xeogl.TeapotGeometry({
       ghostEdgeThreshold: 5
   }),
   material: new xeogl.PhongMaterial({
       diffuse: [0.2, 0.2, 1.0]
   }),
   ghostMaterial: new xeogl.EmphasisMaterial({
       preset: "sepia"
   });
   ghost: true
});

Note that applying a preset just sets the EmphasisMaterial's property values, which you are then free to modify afterwards.

Constructor

EmphasisMaterial

(
  • [scene]
  • [cfg]
)

Parameters:

  • [scene] Scene optional

    Parent Scene, creates this EmphasisMaterial within the default Scene when omitted

  • [cfg] optional

    The EmphasisMaterial configuration

    • [id] String optional

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

    • [meta=null] String:Object optional

      Metadata to attach to this EmphasisMaterial.

    • [edges=true] Boolean optional

      Indicates whether or not ghost edges are visible.

    • [edgeColor=[0.2,0.2,0.2]] Array of Number optional

      RGB color of ghost edges.

    • [edgeAlpha=0.5] Number optional

      Transparency of ghost edges. A value of 0.0 indicates fully transparent, 1.0 is fully opaque.

    • [edgeWidth=1] Number optional

      Width of ghost edges, in pixels.

    • [vertices=false] Boolean optional

      Indicates whether or not ghost vertices are visible.

    • [vertexColor=[0.4,0.4,0.4]] Array of Number optional

      Color of ghost vertices.

    • [vertexAlpha=0.7] Number optional

      Transparency of ghost vertices. A value of 0.0 indicates fully transparent, 1.0 is fully opaque.

    • [vertexSize=4.0] Number optional

      Pixel size of ghost vertices.

    • [fill=true] Boolean optional

      Indicates whether or not ghost surfaces are filled with color.

    • [fillColor=[0.4,0.4,0.4]] Array of Number optional

      EmphasisMaterial fill color.

    • [fillAlpha=0.2] Number optional

      Transparency of filled ghost faces. A value of 0.0 indicates fully transparent, 1.0 is fully opaque.

    • [preset] String optional

      Selects a preset EmphasisMaterial configuration - see EmphasisMaterial/preset:method.

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

edgeAlpha

Number

Transparency of ghost edges.

A value of 0.0 indicates fully transparent, 1.0 is fully opaque.

Default: 0.5

edgeColor

Float32Array

RGB color of ghost edges.

Default: [0.2, 0.2, 0.2]

edges

Boolean

Indicates whether or not ghost edges are visible.

Default: true

edgeWidth

Number

Width of ghost edges, in pixels.

Default: 1.0

fill

Boolean

Indicates whether or not ghost surfaces are filled with color.

Default: true

fillAlpha

Number

Transparency of filled ghost faces.

A value of 0.0 indicates fully transparent, 1.0 is fully opaque.

Default: 0.2

fillColor

Float32Array

RGB color of filled ghost faces.

Default: [0.4, 0.4, 0.4]

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.

metadata

Object

Arbitrary, user-defined metadata on this component.

preset

String

Selects a preset EmphasisMaterial configuration.

Available presets are:

  • "default" - grey wireframe with translucent fill, for light backgrounds.
  • "defaultLightBG" - grey wireframe with grey translucent fill, for light backgrounds.
  • "defaultDarkBG" - grey wireframe with grey translucent fill, for dark backgrounds.
  • "vectorscope" - green wireframe with glowing vertices and black translucent fill.
  • "battlezone" - green wireframe with black opaque fill, giving a solid hidden-lines-removed effect.
  • "sepia" - light red-grey wireframe with light sepia translucent fill - easy on the eyes.
  • "gamegrid" - light blue wireframe with dark blue translucent fill - reminiscent of Tron.
  • "yellowHighlight" - light yellow translucent fill - highlights while allowing underlying detail to show through.

Default: "default"

presets

Object static

Available EmphasisMaterial presets.

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.

vertexAlpha

Number

Transparency of ghost vertices.

A value of 0.0 indicates fully transparent, 1.0 is fully opaque.

Default: 0.7

vertexColor

Float32Array

Color of ghost vertices.

Default: [0.4,0.4,0.4]

vertexSize

Number

Pixel size of ghost vertices.

Default: 4.0

vertices

Boolean

Indicates whether or not ghost vertices are visible.

Default: false

Events

destroyed

Fired when this Component is destroyed.