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EventUtilities

These nodes allow authors to handle numerous event-types for interactive scenes without the use of the Script node.

Each node corresponds to standard VRML node. All field definitions are similar to the ISO/IEC 19775 Abstract Specification. This section provides a detailed definition of the syntax of proposed nodes.

BooleanFilter

EXTERNPROTO BooleanFilter [ 
  eventIn   SFBool set_boolean
  eventOut  SFBool inputFalse
  eventOut  SFBool inputNegate
  eventOut  SFBool inputTrue

]
[
  "urn:inet:parallelgraphics.com:cortona:BooleanFilter"
  "http://www.parallelgraphics.com/vrml/proto/Cortona/extensions.wrl#BooleanFilter"
]

The BooleanFilter node allows routing of boolean values and negation. On receiving the set_boolean TRUE event, the BooleanFilter node generates the inputTrue event, and on receiving FALSE, it generates the inputFalse event. In both cases the BooleanFilter node generates the inputNegate event, which is the negation of the set_boolean value.

BooleanToggle

EXTERNPROTO BooleanToggle [ 
  eventIn       SFBool set_boolean
  exposedField  SFBool toggle    #FALSE
]
[
  "urn:inet:parallelgraphics.com:cortona:BooleanToggle"
  "http://www.parallelgraphics.com/vrml/proto/Cortona/extensions.wrl#BooleanToggle"
]

The BooleanToggle node stores a boolean value in the toggle field and negates it on receiving of the set_boolean TRUE event. The set_boolean FALSE event is ignored.

BooleanTrigger

EXTERNPROTO BooleanTrigger [ 
  eventIn   SFTime set_triggerTime
  eventOut  SFBool triggerTrue
]
[
  "urn:inet:parallelgraphics.com:cortona:BooleanTrigger"
  "http://www.parallelgraphics.com/vrml/proto/Cortona/extensions.wrl#BooleanTrigger"
]

BooleanTrigger is a node that always generates the triggerTrue TRUE event on receiving a set_triggerTime event.

IntegerSequencer

EXTERNPROTO IntegerSequencer [ 
  eventIn       SFBool   next
  eventIn       SFBool   previous
  eventIn       SFBool   set_fraction
  exposedField  MFFloat  key       #[] (-inf,inf)
  exposedField  MFInt32  keyValue  #[] -1|[1,inf)
  eventOut      MFInt32  value_changed

]
[
  "urn:inet:parallelgraphics.com:cortona:IntegerSequencer"
  "http://www.parallelgraphics.com/vrml/proto/Cortona/extensions.wrl#IntegerSequencer"
]

The IntegerSequencer node generates the value_changed event on receiving a set_fraction event. The value of the value_changed event is taken from the keyValue array's element corresponding to the element of the key array the value of which equals to the value of the set_fraction event.

IntegerTrigger

EXTERNPROTO IntegerTrigger [ 
  eventIn       SFBool   set_boolean
  exposedField  SFInt32  integerKey  #1 | (-inf,inf)
  eventOut      SFInt32  triggerValue
]
[
  "urn:inet:parallelgraphics.com:cortona:IntegerTrigger"
  "http://www.parallelgraphics.com/vrml/proto/Cortona/extensions.wrl#IntegerTrigger"
]

On receiving a set_boolean event, the IntegerTrigger node generates the triggerValue event with the current value of integerKey. This is useful for connecting environmental events to the Switch node's whichChoice.

TimeTrigger

EXTERNPROTO TimeTrigger [ 
  eventIn   SFBool set_boolean
  eventOut  SFTime triggerTime
]
[
  "urn:inet:parallelgraphics.com:cortona:TimeTrigger"
  "http://www.parallelgraphics.com/vrml/proto/Cortona/extensions.wrl#TimeTrigger"
]

The triggerTime event is generated on receiving a set_boolean event. The value of triggerTime is the time at which set_boolean is received. The value of set_boolean is ignored.



Last updated: Wed, 19 Nov 2008
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