3 Terms and definitions
3.1 Introduction
For the purposes of this part of ISO/IEC 14772, the terms and definitions given in ISO/IEC 14772-1 and the following apply. Terms from this clause are italicized when used outside their definitions. Other terms are formatted in the normal font.
Table 3.1 defines the contents of this clause
Table 3.1 -- Table of contents
3.2 browser
A computer program that interprets files accessed, presents their content to a user on a display device, and allows the user to interact with them. There may be two forms of browser discussed: a Web Browser and a VRML Browser. When used as an unqualified word within this part of ISO/IEC 14772, the VRML Browser meaning shall be implied.
3.3 event
A message sent from either a node or the browser itself to the external application. Events signal external stimuli, changes to field values, and interactions between nodes. An event consists of at least a timestamp and a field value. There are two forms of events: VRML events that are defined in ISO/IEC 14772-1 and information that is passed from the VRML Browser to the external environment.
3.4 eventIn
A logical receptor attached to a node which receives events. (From ISO/IEC 14772-1)
3.5 eventOut
A logical output terminal attached to a node from which events are sent. The eventOut also stores the event most recently sent. (From ISO/IEC 14772-1)
3.6 exposedfield
A field that is capable of receiving events via an eventIn to change its value(s), and generating events via an eventOut when its value(s) change. (From ISO/IEC 14772-1)
3.7 external
External means anything that exists outside of the VRML Browser environment. This may take the form of a container application that holds a VRML Browser, or a client/server style environment where the VRML Browser forms the client and the application is a server located on a remote machine.
3.8 field
A property or attribute of a node. Each node type has a fixed set of fields. Fields may contain various kinds of data and one or many values. Each field has a default value. (From ISO/IEC 14772-1)
3.9 field name
The identifier of a field. Field names are unique within the scope of the node. (From ISO/IEC 14772-1)
3.10 message
A data string sent between nodes upon the occurrence of an event. See ISO/IEC 14772-1, 4.10, Event processing, for details.
3.11 node
The fundamental component of a scene graph in ISO/IEC 14772. Nodes are abstractions of various real-world objects and concepts. Examples include spheres, lights, and material descriptions. Nodes contain fields and events. Messages may be sent between nodes along routes. (From ISO/IEC 14772-1)
3.12 node type
A characteristic of each node that describes, in general, its particular semantics. For example, Box, Group, Sound, and SpotLight are node types. See ISO/IEC 14772-1, 4.6, Node semantics, and ISO/IEC 14772-1, 6, Node reference, for details. (From ISO/IEC 14772-1)
3.13 route
The connection between a node generating an event and a node receiving the event. See ISO/IEC 14772-1, 4.3.9, Route statement syntax, and ISO/IEC 14772-1, 4.10.2, Route semantics, for details.
3.14 service
The method of interfacing between external applications and the browser.
3.15 token
An application supplied value which is returned with an event to identify the registration for that event.
3.16 URL
Uniform Resource Locator. See 2.[URL].
3.17 URN
Universal Resource Name. See ISO/IEC 14772-1, E.[URN].
3.18 VRML browser
A computer program that interprets VRML files, presents their content to a user on a display device, and allows the user to interact with worlds defined by VRML files by means of a user interface. (See ISO/IEC 14772-1)
3.19 VRML file
A set of VRML nodes and statements as defined in ISO/IEC 14772-1. This set of VRML nodes and statements may be in the form of a file, a data stream, or an in-line sequence of VRML information as defined by a particular VRML encoding. (From ISO/IEC 14772-1)
3.20 Web Browser
A computer program that is used to interpret and display files that have been retrieved over the Internet. Typically, this involves using the HTTP transfer protocol and HTML documents, but may include other types of data.