The Cage class is used to evaluate object's
bounding rectangles.
Properties
top
left
bottom
right
Methods
bool doit(heapPtr
pObj)
Checks pObj's bounding rect properties
(brLeft, brRight, brTop, brBottom) to see if they are all in
the Blk's rect properties (left, right, top, bottom). If they
are, it returns TRUE, otherwise, FALSE.