Copyright (C) 1993, Digital Equipment Corporation
All rights reserved.
See the file COPYRIGHT for a full description.
Last modified on Thu Jul 29 14:43:44 PDT 1993 by bharat
modified on Fri Jul 2 16:33:31 PDT 1993 by mhb
<* PRAGMA LL *>
A KnobsVBT displays little ``knobs'' on its child.
INTERFACE KnobsVBT;
IMPORT Filter, Point, VBT;
TYPE
T <: Public;
Public = Filter.T OBJECT
(* drawColor: Pixmap.T;*)
METHODS
<* LL <= VBT.mu *>
init (ch: VBT.T): T;
END;
The call v.init(ch) initialize v as a KnobsVBT. Initially, ch
is displayed unaltered.
PROCEDURE Add (v: T);
<* LL = VBT.mu *>
Draw a set of ``knobs'' using PaintOp.Fg. This procedure is a no-op
if the knobs are already displayed.
PROCEDURE Remove (v: T);
<* LL = VBT.mu *>
Remove the set of ``knobs.'' This procedure is a no-op is the knobs are
not being displayed.
PROCEDURE Inside (v: T; READONLY pt: Point.T): BOOLEAN;
<* LL = VBT.mu *>
Returns whether the point pt falls within any of the ``knobs.''
PROCEDURE SetSingleMode (v: T; READONLY tv:BOOLEAN);
<* LL = VBT.mu *>
Decides how an active set of knobs will be displayed, gray or black
black if single, gray if multiple
END KnobsVBT.