Mutable Points/Rects in Morphic

Bill Spight bspight at
Mon Feb 17 01:16:42 UTC 2003

Dear Eddie,

Very interesting! Thanks for the info. :-)



> > Hmmm. What about creating a MutableRectangle subclass? Not that you
> > haven't thought of that, but why not? It would be available for those
> > Morphs that need it, and would not bother those that do not use it. (I
> > don't know other alterations would be required to make that option
> > available.)
> I put some effort into seeing how well this would work.
> The main thing that would benefit is Morph's bounds and fullBounds
> variables, which get updated very frequently.
> The tricky thing is that code needs to know whether its dealing with the
> mutable versions or not.
> In an ideal world, I suppose we'd use the mutable bound/fullBounds in
> Morph's private methods. Morph would give out a safe copy for use external
> to the class. But at this point, the implications of messing with this look
> too deep.
> Maybe after the morphic cleaning project has had some time to work it could
> happen. It would be nice, because morphic could probably get 10%-20% more
> speed overall. In addition to the much reduced garbage load, mutable
> versions of Rectangle/Point can do their operations around twice as fast as
> the current ones, and these operations are used very heavily in morphic.

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