V8 Javascript API

Image Class Reference

[Elements]

Description

Represents an Image element. Images are used by Texture to represent the underlying image file.

Constructor

 Image( String name, bool create, Number privacy_level)
More...

Functions

varying as( String type_name)
Upcasts an element to a specific element type. More...
the copy( String name, Number privacy_level)
Make a copy of this element in the database. More...
 create( String element_type, Number privacy_level)
Creates a scene element called name. More...
 delete()
Remove this element from the database.
bool  exists( String element_type)
Returns whether the element exists or not. More...
 localize( Number privacy_level)
Localizes this element. More...
varying property_get( String cache, String command, String element_name_arg, Function as_a)
Retrieves and caches a property of an element. More...
 property_set( String cache, String command, String element_name_arg, String value_arg_name, varying value, Function from_a)
Sets and caches a property of an element. More...
 reset_canvas( the canvas, the selector)
Resets the image to the given canvas with a given selector. More...
 reset_file( the filename, the selector)
Resets the image to file with a given selector. More...
 save_to_disk( String filename, String format, String quality, String pixel_type)
Save image data to disk. More...

Properties

Attributes attributes
The attributes associated with this element.
Canvas canvas
Exposes a Canvas representation of the image. More...
bool  exists
Returns whether the image exists or not. More...
String  filename
The underlying filename represented by this Image. More...
Number  levels
returns the Number of mipmap levels in the image.
String  name
The name of the element. More...
String  original_filename
The unresolved filename provided to the image originally.
String  pixel_type
returns the pixel type of the image.
Uint32_2  resolution
returns the resolution of the image as a Sint32<2>
String  selector
The selector used by the texture, null indicates no selector.
String  type_name
The type name of the element. More...

Constructor

Image( String name, bool create, Number privacy_level)

Parameters

name
The name of the image
create
if true then create the image, otherwise it is assumed it already exists.
privacy_level
if create is true then the privacy level to create the image at. Defaults to privacy level of the current scope.

Functions

varying Image.as( String type_name)

Upcasts an element to a specific element type. If this element is not of the given type then undefined is returned. If type_name does not have a matching element implementation an error is thrown. Note that this is not strictly an upcast but will return a new instance of the specific class representing type_name.

Parameters

type_name
the element type name to convert to.

Returns

the specific Element implementation for this element.

the Image.copy( String name, Number privacy_level)

Make a copy of this element in the database.

Parameters

name
The name of the new element to copy to.
privacy_level
The privacy level to which the element will be copied. Defaults to the privacy level of the current scope.

Returns

copied element

Image.create( String element_type, Number privacy_level)

Creates a scene element called name. Throws on error.

Parameters

element_type
the type of element to create
privacy_level
The privacy level to create the element at. Defaults to the privacy level of the current scope.
Image.delete()

Remove this element from the database.

bool Image.exists( String element_type)

Returns whether the element exists or not.

Note:

element_type of 'Scene' is not supported. To test if a Scene exists use this.as('Scene') !== undefined

Parameters

element_type
if provided then the element must also be of this type.
Image.localize( Number privacy_level)

Localizes this element.

Parameters

privacy_level
The privacy level to which the element will be localized. Defaults to the privacy level of the current scope.
varying Image.property_get( String cache, String command, String element_name_arg, Function as_a)

Retrieves and caches a property of an element. The value of the property must be retrievable via a command that takes a single argument which is the name of the element to retrieve the property from. The name of this Element is used. If the returned property is another named scene Element then the element's constructor can be provided to return the element itself rather than it's name. On error this will return undefined.

Parameters

cache
name of the property to cache the result to
command
name of the RS command to get the property value
element_name_arg
name of the command argument to use for the element name
as_a
if the property being retrieved is an RS Element then the element constructor should be passed in here. The result of the command is assumed to be the element name and this is used to create an Element instance to return rather than the name of the element. Use undefined if the retrieved value is not an element.

Returns

the property value if it exists or undefined

Image.property_set( String cache, String command, String element_name_arg, String value_arg_name, varying value, Function from_a)

Sets and caches a property of an element. The value of the property must be set via a command that takes two arguments, one being the name of the element to set and the other being the property's value. The names of these arguments are passed in. If the property is another named scene Element then the element's constructor can be provided and value can either be the element itself or it's name. Will throw on error.

Parameters

cache
name of the property to cache the result to
command
name of the RS command to set the property value
element_name_arg
name of the command argument to use for the element name
value_arg_name
name of the value argument to use for the value
value
the value to set
from_a
if the property being set is a RealityServer Element then the element constructor should be passed in here. value can then either be the name of the scene element or the Element itself. If value is a name then an Element is constructed and cache rather than the name itself. Use undefined if the value does not represent an Element .
Image.reset_canvas( the canvas, the selector)

Resets the image to the given canvas with a given selector.

Parameters

canvas
canvas
selector
selector to use, defaults to null which is no selector.
Image.reset_file( the filename, the selector)

Resets the image to file with a given selector.

Parameters

filename
path to the image file
selector
selector to use, defaults to null which is no selector.
Image.save_to_disk( String filename, String format, String quality, String pixel_type)

Save image data to disk.

Parameters

filename
the name of the file to save to
format
the file format
quality
the quality used for the file format if supported
pixel_type
optional pixel type to be used when encoding the file

Properties

Attributes Image.attributes

The attributes associated with this element.

Canvas Image.canvas

Exposes a Canvas representation of the image. Getting this property returns a copy of the underlying image as a Canvas, setting to a Canvas replaces the image contents

bool Image.exists

Returns whether the image exists or not. This test is type checked.

String Image.filename

The underlying filename represented by this Image. Set to the filename's path to change the image file used.

Number Image.levels

returns the Number of mipmap levels in the image.

String Image.name

The name of the element. Read only.

String Image.original_filename

The unresolved filename provided to the image originally.

String Image.pixel_type

returns the pixel type of the image.

Uint32_2 Image.resolution

returns the resolution of the image as a Sint32<2>

String Image.selector

The selector used by the texture, null indicates no selector.

String Image.type_name

The type name of the element. If the element does not exists returns undefined. Read only.

Note:

For a Scene element this will return 'Attribute_container', not 'Scene'.