Shape - what shape a canvas should have

SYNOPSIS

       #include <InterViews/shape.h>

DESCRIPTION

       A shape specifies the desired characteristics of a canvas.
       An interactor should set the fields of its shape  when  it
       is  reconfigured  and  should call Change on its parent if
       any of these fields change.

       The dimensions of a shape are  defined  by  a  ``natural''
       size,  a  stretch  amount, and a shrink amount.  The width
       and  height  fields  indicate  the  desired  sizes.    The
       hstretch,  vstretch,  hshrink,  vshrink  fields define how
       flexible these desired sizes are.  For example, an  inter-
       actor  may  have a natural size of 100, but can adequately
       handle any size between 50 and  200.   The  stretchability
       for this case would be 100 and the shrinkability 50.

       The  constants  hfil  and  vfil  are  provided to indicate
       ``infinite'' stretching or  shrinking.   They  are  repre-
       sented  as  very large numbers and manipulated exactly the
       same as other stretch and shrink parameters.

       The aspect field specifies the desired  aspect  ratio.   A
       value of zero means any aspect is acceptable.

       The  hunits  and  vunits  fields  indicate that the canvas
       dimensions should be multiples of some values.

PUBLIC OPERATIONS

       Shape()
              Construct a new shape with undefined  natural  size
              and  infinite  stretchability  and shrinkability in
              both directions.

       boolean Defined()
       boolean Undefined()
              Test if the shape's natural size is defined or not.

       void Rect(int width, int height)
       void Square(int side)
              Short-hand for setting the dimensions of the shape.
              Square sets both dimensions to side  and  sets  the
              aspect ratio to one.

       void Rigid(int hshrink, int hstretch, int vshrink, int
              vstretch)
       void Rigid()
              Set the stretchability and shrinkability fields  of
              the  shape.   If  no  arguments  are specified, the
              Reset the shape's natural size to be undefined.

SEE ALSO

       Interactor(3I), Scene(3I)