vrml.node

Base-class for scenegraph nodes
Requires Python 2.2.x, as it makes extensive use of properties

Functions

_changeSender( nodeRef , field )
Utility function to send node-change messages on olist updates
ismaps( node )
Get the isMaps for the given node
Returns a field-name:(sub-node,field) mapping Not currently functional
prototype( name , fields = () , sceneGraph = None , externalURL = None , baseClasses = (<class 'vrml.node.PrototypedNode'>, <class 'vrml.node.Node'>) )
Build a new prototype class
name
string name
fields
sequence of vrml.field objects
sceneGraph
the source scenegraph for prototyped nodes
externalURL
MFString URL or None
baseClasses
base classes for the new class

Classes

class _MFNode( object ):
(Restricted) MFNode field-type-definition
baseSFNode
exposedField SFNode SFNode <bound method SFNode
coerce( self , value )
Coerce value to an MFNode list-of-objects
copyValue( self , value , copier = None )
Copy a value for copier
fset( self , client , value , notify = 1 )
Set the client's value for this property
notify
if true send a notification event
The MFNode tries to update the value's root attribute to point to the root of the client *iff* the value doesn't currently point at a valid root. (That is, it only updates root if there is no current root). This is done without sending notify events.
vrmlstr( self , value , lineariser )
Convert the given value to a VRML97 representation
class _SFNode( object ):
Base-class for SFNode-type fields
The optionally restricted SFNode field type allows a node to hold a reference to another node within the directed acyclic graph.
There are two primary attributes:
requiredTypes
a type or tuple of types that are acceptable as values for the field
allowNULL
whether to allow the NULL node as a value for the field
coerce( self , value )
Coerce value to an SFNode reference
defaultDefault( self )
Default SFNode value
fset( self , client , value , notify = 1 )
Set the client's value for this property
notify
if true send a notification event
The SFNode tries to update the value's root attribute to point to the root of the client *iff* the value doesn't currently point at a valid root. (That is, it only updates root if there is no current root). This is done without sending notify events.
vrmlstr( self , value , lineariser )
Convert the given value to a VRML97 representation
class MFNode( _MFNodeField ):
MFNode Field class
class MFNodeEvt( _MFNodeEvent ):
MFNode Event class
class Node( object ):
A generic scene graph node
Unlike earlier versions of the library, this implementation of the Node class is basically a regular python class. This is possible because it uses the python 2.2.x property/descriptor API extensively.
Technically this is a multiple-hierarchy DAG node, as there can be any number of node children attributes, and nodes may appear multiple times in the hierarchy.
Attributes of note: " DEF" field a simple string field which stores the DEF name of a node instance " scenegraph" attribute pointer to the node's implementation scenegraph (at the moment, this is not actually used for anything) " PROTO" attribute stores the PROTO name of the node externalURL attribute stores the MFString url for the node's externproto definition if appropriate toString method convenience access to the lineariser to give VRML97-formatted representation of the node
DEF
exposedField SFString DEF
externalURL
exposedField MFString externalURL []
rootSceneGraph
exposedField RootScenegraphNode SFNode NULL
__init__( self , ** namedarguments )
Initialise the node with appropriate named args
All properties/attributes must be specified with named arguments, and the property/attribute must exist within the Node's class/prototype.
This will raise AttributeError/ValueError/TypeError if the values or the property names are inappropriate.
Note that all Node objects have the attribute/property exposedField SFString DEF "" defined. You may therefore specify a DEF name by passing it as a named argument.
__repr__( self )
Get a code-like representation of the Node
Basically every attribute except for sub-nodes values are returned as a full representation.
__str__( self )
Get a friendly representation of the Node
copy( self , copier = None )
Copy this node for copier
toString( self , ** namedargs )
Generate a VRML 97-syntax string representing this Prototype **namedargs -- key:value passed arguments for the linearisation object see lineariser4.Lineariser
class NullNode( Node ):
NULL SFNode value There should only be a single NULL instance for any particular system. It should, for all intents and purposes just sit there inertly
__eq__( self , other )
Compare the NULL node to other objects
__nonzero__( self )
Make the NULL node evaluate to false
__repr__( self )
Get a human-friendly representation of the NULL node
__str__( self )
Get a human-friendly representation of the NULL node
clone( self )
Replicate the null object (return another pointer to it)
class PrototypedNode( object ):
Prototyped node mix-in
Note the presence of a " scenegraph" property for the node created below (due to mutual dependencies). This is filled by the instantiate method to provide the actual implementation of the node.
scenegraph
exposedField SFNode SFNode NULL
__init__( self , * arguments , ** namedarguments )
Initialise the node with appropriate named args
Also attempts to instantiate the sub-node scenegraph for the PrototypedNode
instantiate( self )
Make a copy of the class scenegraph-template for this node
Also needs to bind IS mappings/routes for the template, and negotiate not-yet-loaded external prototypes and the like.
renderedChildren( self , types = None )
Get the rendered children of the scenegraph
class RootScenegraphNode( WeakSFNode ):
fset( self , client , value , notify = 1 )
Set the root scenegraph node (recursively)
TODO: this will blow up on cyclic graphs!
class SFNode( _SFNodeField ):
(Restricted) SFNode type
This is the publically available SFNode type, a sub-class of _SFNode and field.Field
class SFNodeEvt( _SFNodeEvent ):
class WeakSFNode( _SFNodeWeakFieldField ):
Weak-referenced SFNode field-type