This section provides a detailed description of each node in VRML 2.0. There is a helpful table of contents at the top organized functionally. However, the nodes are listed alphabetically. (An alphabetical Index of Nodes and Fields is also available.)

This document's URL: http://vrml.sgi.com/moving-worlds/spec/BNF.html

This section describes the syntax (grammar) of the Moving Worlds human-readable file format.

This grammar is ambiguous; semantic knowledge of the names and types of fields, eventIns, and eventOuts for each node type (either builtIn or userDefined using PROTO or EXTERNROTO) must be used during parsing so that the parser knows which field type is being parsed.

The '#' (0x23) character begins a comment wherever it appears outside of quoted SFString or MFString fields. The '#' character and all characters until the next carriage-return or newline make up the comment and are treated as whitespace.

The carriage return (0x0d), newline (0x0a), space (0x20), tab (0x09), and comma (0x2c) characters are whitespace characters wherever they appear outside of quoted SFString or MFString fields. Any number of whitespace characters and comments may be used to separate the syntactic entities of a VRML file.

Please see the Nodes Reference section of the Moving Worlds specification for a description of the allowed fields, eventIns and eventOuts for all pre-defined node types. Also note that some of the basic types that will typically be handled by a lexical analyzer (sffloatValue, sftimeValue, sfint32Value, and sfstringValue) have not been formally specified; please see the Fields Reference section of the spec for a more complete description of their syntax.

General

vrmlScene:

declarations

declarations:

declaration

declaration declarations

declaration:

nodeDeclaration

protoDeclaration

routeDeclaration

nodeDeclaration:

node

DEF nodeNameId node

USE nodeNameId

protoDeclaration:

proto

externproto

proto:

PROTO nodeTypeId [ interface_declarations ] { vrmlScene }

interfaceDeclarations:

interfaceDeclaration

interfaceDeclaration interfaceDeclarations

restrictedInterfaceDeclaration:

eventIn fieldType eventInId

eventOut fieldType eventOutId

field fieldType fieldId fieldValue

interfaceDeclaration:

restrictedInterfaceDeclaration

exposedField fieldType fieldId fieldValue

externproto:

EXTERNPROTO nodeTypeId [ externInterfaceDeclarations ] mfstringValue

externInterfaceDeclarations:

externInterfaceDeclaration

externInterfaceDeclaration externInterfaceDeclarations

externInterfaceDeclaration:

eventIn fieldType eventInId

eventOut fieldType eventOutId

field fieldType fieldId

exposedField fieldType fieldId

routeDeclaration:

ROUTE nodeNameId . eventOutId TO nodeNameId . eventInId

Nodes

node:

nodeTypeId { nodeGuts }

Script { scriptGuts }

nodeGuts:

nodeGut

nodeGut nodeGuts

scriptGuts:

scriptGut

scriptGut scriptGuts

scriptGut:

nodeGut

restrictedInterfaceDeclaration

nodeGut:

fieldId fieldValue

fieldId IS fieldId

eventInId IS eventInId

eventOutId IS eventOutId

routeDeclaration

protoDeclaration

nodeNameId:

Id

nodeTypeId:

Id

fieldId:

Id

eventInId:

Id

eventOutId:

Id

Id:

IdFirstChar

IdFirstChar IdRestChars

IdFirstChar:

Any ISO-10646 character encoded using UTF-8 except: 0x30-0x39, 0x0-0x20, 0x22, 0x23, 0x27, 0x2c, 0x2e, 0x5b, 0x5c, 0x5d, 0x7b, 0x7d.

IdRestChars:

Any number of ISO-10646 characters except: 0x0-0x20, 0x22, 0x23, 0x27, 0x2c, 0x2e, 0x5b, 0x5c, 0x5d, 0x7b, 0x7d.

Fields

fieldType:

MFColor

MFFloat

MFInt32

MFNode

MFRotation

MFString

MFVec2f

MFVec3f

SFBool

SFColor

SFFloat

SFImage

SFInt32

SFNode

SFRotation

SFString

SFTime

SFVec2f

SFVec3f

fieldValue:

sfboolValue

sfcolorValue

sffloatValue

sfimageValue

sfint32Value

sfnodeValue

sfrotationValue

sfstringValue

sftimeValue

sfvec2fValue

sfvec3fValue

mfcolorValue

mffloatValue

mfint32Value

mfnodeValue

mfrotationValue

mfstringValue

mfvec2fValue

mfvec3fValue

sfboolValue:

TRUE

FALSE

sfcolorValue:

float float float

sffloatValue:

... floating point number in ANSI C floating point format...

sfimageValue:

int32 int32 int32 int32s...

sfint32Value:

[0-9]+

0x[0-9A-F]+

sfnodeValue:

nodeDeclaration

NULL

sfrotationValue:

float float float float

sfstringValue:

".*" ... double-quotes must be \", backslashes must be \\...

sftimeValue:

... double-precision number in ANSI C floating point format...

sfvec2fValue:

float float

sfvec3fValue:

float float float

mfcolorValue:

sfcolorValue

[ ]

[ sfcolorValues ]

sfcolorValues:

sfcolorValue

sfcolorValue sfcolorValues

mffloatValue:

sffloatValue

[ ]

[ sffloatValues ]

sffloatValues:

sffloatValue

sffloatValue sffloatValues

mfint32Value:

sfint32Value

[ ]

[ sfint32Values ]

sfint32Values:

sfint32Value

sfint32Value sfint32Values

mfnodeValue:

nodeDeclaration

[ ]

[ nodeDeclarations ]

nodeDeclarations:

nodeDeclaration

nodeDeclaration nodeDeclarations

mfrotationValue:

sfrotationValue

[ ]

[ sfrotationValues ]

sfrotationValues:

sfrotationValue

sfrotationValue sfrotationValues

mfstringValue:

sfstringValue

[ ]

[ sfstringValues ]

sfstringValues:

sfstringValue

sfstringValue sfstringValues

mfvec2fValue:

sfvec2fValue

[ ]

[ sfvec2fValues]

sfvec2fValues:

sfvec2fValue

sfvec2fValue sfvec2fValues

mfvec3fValue:

sfvec3fValue

[ ]

[ sfvec3fValues ]

sfvec3fValues:

sfvec3fValue

sfvec3fValue sfvec3fValues