NAME

       PadComp,  PadView,  PadGraphic,  PSPad  - pad connector subject, view, structured graphic, and PostScript
       external representation

SYNOPSIS

       #include <Unidraw/Components/pad.h>

DESCRIPTION

       PadComp is a Connector subclass that supports connectivity with  two  degrees  of  freedom.   It  uses  a
       PadGraphic to store its graphical attributes.  PadView is a GraphicView for displaying the pad.  PSPad is
       a PostScriptView that externalizes the subject's information in PostScript form.

PADCOMP PUBLIC OPERATIONS

       PadComp(PadGraphic* = nil)
              The constructor takes an optional PadGraphic that defines the pad's graphical attributes.

       virtual void Interpret(Command*)
       virtual void Uninterpret(Command*)
              PadComp  (un)interprets  a  subset  of  commands  that  connectors can generally interpret, namely
              MoveCmd, BrushCmd, AlignCmd, MobilityCmd, DeleteCmd, and CutCmd.

       virtual Mobility GetMobility()
       virtual void SetMobility(Mobility)
              PadComp redefines these functions to return and assign its _mobility protected  member.   The  pad
              has fixed mobility initially.

       Pad* GetPad()
              Return  the Pad graphic that defines the line's attributes.  GetPad is simply a more specific form
              of the GetGraphic operation.

PADVIEW PUBLIC OPERATIONS

       PadView(PadComp* = nil)
              Create an PadView, optionally supplying the subject.

       virtual void Interpret(Command*)
              PadView interprets AlignToGridCmd to align its lower left to the grid.

       virtual Manipulator* CreateManipulator(
          Viewer*, Event&, Transformer*, Tool*
       )

       virtual void InterpretManipulator(Manipulator*)
              PadViews respond only to manipulation by GraphicCompTools, MoveTools,  and  ConnectTools.  PadView
              inherits  its MoveTool response from ConnectorView.  GraphicCompTool will let the user sweep out a
              rectangle that reflects the pad's size.  Creation will be influenced by gravity, if  any.  PadView
              creates a ConnectManip in response to the ConnectTool, which will exhibit a gravational attraction
              to  potential  target  connectors.   PadView  will  produce a ConnectCmd to connect the pad to its
              target. A pad connected in this way will receive floating mobility.

       PadComp* GetPadComp()
              Return the subject.

PADVIEW PROTECTED OPERATIONS

       PadGraphic* GetPad()
              Return the PadGraphic that defines the pad's attributes.  GetPad is simply a more specific form of
              the GetGraphic operation.

       virtual PadComp* NewSubject(PadGraphic*)
              A helper function that creates a PadComp  subject  with  the  given  pad  graphic.  This  function
              produces the proper subject when the GraphicCompTool's manipulator is interpreted.  Subclasses can
              redefine  this  operation  to  return a PadComp subclass, thus eliminating the need to reimplement
              InterpretManipulator.

       Manipulator* CreateGraphicCompManip(
           Viewer*, Event&, Transformer*, Tool*
       )

       Manipulator* CreateConnectManip(
           Viewer*, Event&, Transformer*, Tool*
       )

       Command* InterpretGraphicCompManip(Manipulator*)
       Command* InterpretConnectManip(Manipulator*)
              Helper functions used by CreateManipulator and InterpretManipulator to create  and  interpret  the
              manipulators associated with GraphicCompTool and ConnectTool.

PADGRAPHIC PUBLIC OPERATIONS

       PadGraphic(
           Coord = 0, Coord = 0, Coord = 0, Coord = 0,
           Graphic* = nil
       )
              Create  a  PadGraphic, optionally specifying lower-left and upper-right corners and a graphic from
              which to obtain its default graphics attributes.

       void GetOriginal(Coord&, Coord&, Coord&, Coord&)
              Return the PadGraphic's original coordinates as specified in the constructor.

PSPAD PUBLIC OPERATIONS

       PSPad(PadComp* = nil)
              Construct a PostScript external representation of the given subject, if any.

SEE ALSO

       BrushCmd(3U),    ConnectTool(3U),    Connector(3U),     ConnectorView3U),     Event(3I),     Graphic(3U),
       GraphicCompTool(3U),   Grid(3U),   MoveTool(3U),   PatternCmd(3U),  PostScriptView(3U),  Transformer(3I),
       Viewer(3U), align(3U), edit(3U), manips(3U), transforms(3U)

Unidraw                                          23 January 1991                                     PadComp(3U)