API Docs for: 0.7.0

HeightmapGeometry

Extends Geometry
Module: geometry
Parent Module: xeogl

A Heightmap extends Geometry to define a height mapped geometry for attached Entities.

Overview

  • A HeightmapGeometry is a grid shape, to which the Y-axis is perpendicular.
  • The height of each vertex on the Y-axis is determined by the image file referenced by the HeightmapGeometry's src property.
  • Set the src property to a different image file at any time, to regenerate the HeightmapGeometry's mesh from the new image.
  • Also dynamically modify it's shape at any time by updating its center, xSize, ySize, zSize, xSegments, zSegments and Geometry/autoNormals:property properties.
  • Dynamically switch its primitive type between "points", "lines" and "triangles" at any time by updating its primitive property.
  • Leave its Geometry/autoNormals:property property true to make it automatically generate its vertex normal vectors.

Examples

Usage

new xeogl.Entity({
    geometry: new xeogl.HeightmapGeometry({
        primitive: "triangles",
        src: "textures/height/mountain.png",
        center: [0,0,0],
        xSize: 10,
        ySize: 5,
        zSize: 10,
        xSegments: 70,
        zSegments: 70,
        lod: 1.0, // Default
        autoNormals: true // Default
    }),
    material: new xeogl.PhongMaterial({
        diffuseMap: new xeogl.Texture({
            src: "textures/diffuse/uvGrid2.jpg"
        }),
        backfaces: true // So that we can see the faces from underneath
    })
});

Constructor

HeightmapGeometry

(
  • [scene]
  • [cfg]
)

Parameters:

  • [scene] Scene optional

    Parent Scene - creates this Heightmap 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 Heightmap.

    • [primitive="triangles"] String optional

      The primitive type. Accepted values are 'points', 'lines', 'line-loop', 'line-strip', 'triangles', 'triangle-strip' and 'triangle-fan'.

    • [src=undefined] String optional

      Path to an image file to source this Heightmap from.

    • [image=undefined] HTMLImageElement optional

      An HTML DOM Image object to source this Heightmap from.

    • [center] Float32Array optional

      3D point indicating the center position of the BoxGeometry.

    • [xSize=1] Number optional

      Dimension on the X-axis.

    • [ySize=0.25] Number optional

      Dimension on the Y-axis.

    • [zSize=1] Number optional

      Dimension (height) on the Z-axis.

    • [xSegments=1] Number optional

      Number of segments on the X-axis (width).

    • [zSegments=1] Number optional

      Number of segments on the Z-axis (depth).

    • [autoNormals=true] Boolean optional

      Automatically generate vertex normal vectors when true.

    • [lod=1] Level-of-detail, in range [0..1] Number optional

      .

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

aabb

Float32Array final

Local-space axis-aligned 3D boundary (AABB) of this geometry.

The AABB is represented by a six-element Float32Array containing the min/max extents of the axis-aligned volume, ie. [xmin, ymin,zmin,xmax,ymax, zmax].

center

Float32Array

3D point indicating the center position of this HeightmapGeometry.

Fires an center event on change.

Default: [0,0,0]

colors

Float32Array

The Geometry's vertex colors.

Default: null

combined

Boolean final

Indicates if this Geometry is combined.

Combination is an internally-performed optimization which combines positions, colors, normals and UVs into the same WebGL vertex buffers with other Geometries, in order to reduce the number of buffer binds performed per frame.

Default: false

destroyed

Boolean

True as soon as this Component has been destroyed

id

String final

Unique ID for this Component within its parent Scene.

image

HTMLImageElement

Indicates an HTML DOM Image object to source this Heightmap from.

Alternatively, you could indicate the source via the Heightmap/src:property property.

Fires an Heightmap/image:event event on change.

Sets the Heightmap/src:property to null.

Default: null

indices

Uint16Array | Uint32Array final

The Geometry's indices.

If xeogl.WEBGL_INFO.SUPPORTED_EXTENSIONS["OES_element_index_uint"] is true, then this can be a Uint32Array, otherwise it needs to be a Uint16Array.

Default: null

isDefault

Boolean

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

lod

Number

The Heightmap's level-of-detail factor.

Fires a Heightmap/lod:event event on change.

Default: 1

metadata

Object

Arbitrary, user-defined metadata on this component.

normals

Float32Array

The Geometry's vertex normals.

Default: null

obb

Float32Array final

Local-space oriented 3D boundary (OBB) of this geometry.

The OBB is represented by a 32-element Float32Array containing the eight vertices of the box, where each vertex is a homogeneous coordinate having [x,y,z,w] elements.

positions

Float32Array

The Geometry's vertex positions.

Default: null

primitive

String

The Geometry's primitive type.

Valid types are: 'points', 'lines', 'line-loop', 'line-strip', 'triangles', 'triangle-strip' and 'triangle-fan'.

Default: "triangles"

quantized

Boolean final

Indicates if this Geometry is quantized.

Compression is an internally-performed optimization which stores positions, colors, normals and UVs in quantized and oct-encoded formats for reduced memory footprint and GPU bus usage.

Quantized geometry may not be updated.

Default: false

scene

Scene final

The parent Scene that contains this Component.

src

String

Indicates a path to an image file to source this Heightmap from.

Alternatively, you could indicate the source via the Heightmap/image:property property.

Fires a Heightmap/src:event event on change.

Sets the Heightmap/image:property to null.

Default: null

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.

uv

Float32Array

The Geometry's UV coordinates.

Default: null

xSegments

Number

The Heightmap's number of segments on the X-axis.

Fires a Heightmap/xSegments:event event on change.

Default: 100

xSize

Number

The Heightmap's dimension on the X-axis.

Fires a Heightmap/xSize:event event on change.

Default: 1

ySize

Number

The Heightmap's dimension on the Y-axis.

Fires a Heightmap/ySize:event event on change.

Default: 0.25

zSegments

Number

The Heightmap's number of segments on the Z-axis.

Fires a Heightmap/zSegments:event event on change.

Default: 100

zSize

Number

The Heightmap's dimension (height) on the Z-axis.

Fires a Heightmap/zSize:event event on change.

Default: 1.0

Events

boundary

Fired whenever this Geometry's boundary changes.

Get the latest boundary from the Geometry's aabb and obb properties.

center

Fired whenever this HeightmapGeometry's center property changes.

Event Payload:

  • value Float32Array

    The property's new value

destroyed

Fired when this Component is destroyed.

image

Fired whenever this Heightmap's Heightmap/image:property property changes.

Event Payload:

  • value HTML Image

    The property's new value

image

Fired whenever this Heightmap's Heightmap/image:property property changes.

Event Payload:

  • value HTML Image

    The property's new value

loaded

Fired whenever this HeightmapGeometry has rebuilt itself after an update to the Heightmap/src:property or Heightmap/image:property properties.

Event Payload:

  • value Heightmap

    This Heightmap

lod

Number

Fired whenever this Heightmap's Heightmap/lod:property property changes.

Event Payload:

  • value Object

    The property's new value

src

String

Fired whenever this Heightmap's Heightmap/src:property property changes.

Event Payload:

  • value Object

    The property's new value

xSegments

Number

Fired whenever this Heightmap's Heightmap/xSegments:property property changes.

Event Payload:

  • value Object

    The property's new value

xSize

Number

Fired whenever this Heightmap's Heightmap/xSize:property property changes.

Event Payload:

  • value Object

    The property's new value

ySize

Number

Fired whenever this Heightmap's Heightmap/ySize:property property changes.

Event Payload:

  • value Object

    The property's new value

zSegments

Number

Fired whenever this Heightmap's Heightmap/zSegments:property property changes.

Event Payload:

  • value Object

    The property's new value

zSize

Number

Fired whenever this Heightmap's Heightmap/zSize:property property changes.

Event Payload:

  • value Object

    The property's new value