Extensible 3D (X3D)
Part 1: Architecture and base components
3 Definitions, acronyms, and abbreviated terms
3.1 DefinitionsFor the purposes of this document , the following definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
cause a sensor node to generate an isActive event
node which is an antecedent of another node in the transformation hierarchy
structured collection of nodes that process audio inputs and outputs
person or agent that creates X3D files
See generator.
abstract representation of the user in an X3D world
straight line passing through the pointer location in the direction of the pointer
node that may have many instances in a scene graph but only one instance may be active at any instant of time
computer program that interprets X3D files, presents their content to a user on a display device, and allows the user to interact with worlds defined by X3D files by means of a user interface
nodes defined using the prototyping mechanism that are understood only by certain browsers
node of a type explicitly defined in this document
function defined in a scripting language to which events are passed
instance of a children node
one of a set of node types, instances of which can be collected in a group to share specific properties dependent on the type of the grouping node
computer system, attached to a network, that relies on another computer (the server) for essential processing functions
node used as a substitute for all of a Collision node's children during collision detection
characterization of a colour space in terms of explicit parameters
process of identifying objects or parts of objects which do not need to be processed further by the browser in order to produce the desired view of a world
node which descends from another node in the transformation hierarchy (a children node)
graphics device on which X3D worlds may be rendered
pointing device sensor that causes events to be generated in response to sensor-dependent pointer motions
sensor node that generates events based on the location of the viewpoint in the world or in relation to objects in the world
message sent from one node to another as defined by a ROUTE
sequence of events initiated by a script or sensor event and propagated from node to node along one or more routes all of which are considered to have occurred simultaneously
(see Concepts, 4.4.8.3 Execution model)
rules governing how events are processed by browsers and scripts
prototype defined in an external file and referenced by a URL
property or attribute of a node
identifier of a field
single rendering of a world on a display device or a single time-step in a simulation
computer program which creates X3D files
node defining the properties of a specific geometry node
node containing mathematical descriptions of points, lines, surfaces, text strings and solids
receive events from activated pointing devices
one of a set of node types which include a list of nodes, referred to as its children nodes
client application with which the browser communicates using the SAI
two-dimensional (2D) rectangular array of pixel values
creating the illusion of being inside a computer-generated scene
mechanism by which one X3D file is hierarchically included in another
the node created by an instantiation
the creation of a node based on its node type
node that defines a piece-wise or smoothly continuous interpolation
private network that uses the same protocols and standards as the Internet
amount of detail or complexity which is displayed at any particular time for any particular object
linefeed character (0x0A) and/or carriage return character (0x0D)
sequence of events which would result in a specific event generator sending more than one event with the same timestamp
integrated presentation, typically on a computer, of content of various types, such as computer graphics, audio, and video
set of interconnected computers
fundamental component of a scene graph that defines model information, such as graph structure, geometry, animation, interaction, object metadata, rendering, or display
characteristic of each node that describes, in general, its particular semantics
collection of data and procedures, packaged according to the rules and syntax defined in this document
NOTE This term is usually synonymous with node.
order (specified by the user) in which a list of field values is processed by the browser
background texture that is placed behind all geometry in the scene and in front of the ground and sky
node which is an instance of a grouping node
one element of an image specified as a matrix of colour elements
location and direction in the virtual world defined by the pointing device with which the user is currently interacting with the virtual world
hardware device connected to the user's computer by which the user directly controls the location and direction of the pointer
sensor node that generates events based on user actions, such as pointing device motions or button activations
piecewise linear curve
named collection of criteria for functionality and conformance that defines an implementable subset of a standard
definition of a new node type in terms of the nodes defined in this document
mechanism for extending the set of node types from within a X3D file
connection between a node generating an event and a node receiving the event
ordered set of nodes and statements
set of procedural functions normally executed as part of an event cascade
process of creating or referring to a script
system of syntactical and semantic constructs used to define and automate procedures and processes on a computer
node that enables the user to interact with the world in the scene graph hierarchy
UTF-8 character used to separate syntactical entities in an X3D file
node which shares a parent with other nodes
smallest time unit capable of being identified in a digital simulation of analog time
spherical linear interpolation for animating 3D rotation values
grouping node that exhibits special behaviour ( e.g., Switch or LOD)
A statement specifies fundamental scene-related information
pixel in an image used as a texture
image used to create visual appearance effects when applied to geometry nodes
set of coordinates used to map a texture to geometry
monotonically increasing value generated by a node
that part of an event that describes the time the event occurred and that caused the message to be sent
subset of the scene graph consisting of nodes that have well-defined coordinate systems
section of a PNG file containing transparency information (derived from ISO/IEC 15948)
process the nodes in a scene graph in the correct order
person or agent who uses and interacts with X3D files by means of a browser
location, direction, and viewing angle in a virtual world that determines the portion of the virtual world presented by the browser to the user
See world.
one or more consecutive occurrences of a separator character
collection of one or more X3D files (potentially including other multimedia content) that is interpreted by an X3D browser to present an interactive experience to the user that is consistent with the intent of the author
coordinate system in which each X3D world is defined
See browser.
computer program that locates and transmits X3D files and supporting files in response to requests from browsers
set of X3D nodes and statements as defined in this document
plane perpendicular to the Z-axis that passes through the point Z = 0.0
plane perpendicular to the X-axis that passes through the point X = 0.0
plane perpendicular to the Y-axis that passes through the point Y = 0.0
3.2 Acronyms and abbreviated terms For the purposes of this document, the following expansion of acronyms and abbreviated terms apply:
Computer-Assisted Design
Hue, Saturation, and Value colour model
Joint Photographic Experts Group
Musical Instrument Digital Interface. A standard for digital music representation
Multipurpose Internet Mail Extension
Multiple-valued field
(see Field type reference, 5.2.2 X3DArrayField)
Moving Picture Experts Group
Portable Network Graphics. A specification for representing two-dimensional images in files
Red, Green, and Blue colour model
Relative Uniform Resource Locator
Scene Access Interface
Single-valued field
(see Field type reference, 5.2.3 X3DField)
Universal multiple-octet coded Character Set
Universal Resource Identifier
Uniform Resource Locator
Universal Resource Name
variable-length 8-bit Universal multiple-octet coded character set Transformation Format