Points v2.0 - DMS - Oct. '98 - by Marc BARILLEY
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Description
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This module is a kind of points, in a railway sense.

Editor
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Choose the initial state of the points : left or right.
Choose if the changes made on the points reflect or not on all clients

Actions
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  - register : registers a new client for monitoring
  - unregister : unregisters a client
  - shuntRight : shunts the points right
  - shuntLeft : shunts the points left
  - toggle : toogles the points
  - input : depending on the state of the points, this will activate the "left" or the "right" event.

Events
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  - registered : a new client has been successfully added
  - unregistered : a client has been successfully removed
  - right : see action "input".
  - left : see action "input".

Tips
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This module could be used as a lock. Suppose you have one 3D-cell with a door and a knob to lock this door. If a user clicks on the knob, this locks/unlocks the door. Then you should have the following scheme :

 ---------+-------------------             
 |        |                  |             
 |  ------+-------     ------+-----      The two POINTS are supposed to be in the
 |  |    knob    |     |  toggle  |      same initial state. Here, we use the "left"
 |  |            |     |          |      event, but you could use the "right" as well.
 |  |  3D CELL   |     |          |
 |  |            |     |  POINTS  |
 |  |       entry+---  |          |
 |  | exit       |  |  |          |
 |  ---+----------  ---+left    in+--
 |     |               ------------
 |     |
 |  ---+--------
 |  |  in      |
 |  |          |
 |  |  POINTS  |
 |  |          |
 |--+toggle    |
    |          |
    |  left    |
    ----+-------
        |
        |