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    See operating CAD ..

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    Checkbox Interaction:

    Every CAD object can be connected with a function.
    Selection of the object starts the function.

      OFF: Interaction will not be done.

      ON:  Interaction will be done.
           You can select only objects with interaction.

    Identification code for Interactions is letter "I".

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    Interact.connect
    Connect a CAD object with an interaction.
       Selecting the CAD objects (Anchor object) triggers the interaction.
       anchor-object can be any object.

    Examples of interactions are:
      - Load a model (such as HTM-HREF; LDMOD)
      - Change the View position (Change view VIEW)
      - Start/Run a plug-in program (DLL) (EXECM)
      - modify a numeric value (MODVAL)
      - use already defined interaction for another object

      connect object      select an existing anchor-object
      command             commantext, see below

    command:
       - Load a model:
           LOAD "SymbolicDirectory/Model Name"
       - Viewport change:
           VIEW (ViewPortData)
           With Insert/View port (or Alt-Shift-V) you can generate
           the current viewport data.
       - Starting a Plug-in Program (DLL):
           EXECM {DLL-Name}
       - Modify a numeric value (eg. variable 20):
           MODVAL V20
         modify the y-value (the second value) of point P25 (P25=P(100 200 0))
           MODVAL P25 1
       - use already defined interaction I20 for new anchor-object
           I20

    Interaction Format:
    I# = {anchor-object} {command}

    Examples:

    # select P20 to modify V20
    V20=VAL(100)
    P20=P(V20 100 0)
    I20=P20 "MODVAL V20"
    #

    # select circle or tag
    V20=10
    P20=P(0 0 0)
    C20=P20 V20
    # info only
    N21=TAG P(10 0 10) "sel. circ to mod. radius"
    # modify radius of C20
    I21=C20 "MODVAL V20"
    # modify z-value of P20
    N20=TAG P(10 0) 0 "modify-z-of-P20"
    I20=N20 "MODVAL P20 2"
    #

    # Selecting Model1 activates the specified port view.
    I1 = M1 "VIEW ..."

    # Selection of text 20 loads the model Assy_H86.
    I2 = N20 "LDMOD Data/Assy_H86"

    # Selecting Note 20 starts the plug-in program tst3.so.
    I3 = N20 "EXECM tst3"

    # using same interaction for another object:
    I20 = N20 'VIEW ... "
    I21 = N21 I20