Re: [Squeak-VMdev] Host windows

[Andreas R. <and...@gm...>]

Tim,

> The obvious corollary is that if paint events only pass the damage
> rectangle up to the image, then ioShowDisplay is called to move pixels
> to the buffer and that is it. No actual displaying to glass. If I left
> in the code to report the damage area I'd get a nice loop :-)  So any
> VM that buffers the window has to actually handle the paint events and
> not pass them up, and we have to remember not to put anything in the
> image that relies on getting those events. That's all I meant when
> refering to portability.

Yup, but that isn't a problem. Not reporting paint events is equivalent to
being the front-most window which is a very common situation. I wouldn't
expect any trouble here.

> John mentioned that OSX is double buffering the windows so it might be
> an issue for him. And I hear the M$ is making big changes in their
> graphics model for this avalon thingy; maybe they'll require apps to
> report damage areas and only display pixels during a paint event handler
> critical block?

I'd be surprised to see this. But it wouldn't be hard to work around these
restrictions in a way that uses the same model.

> Well of course, but portability includes across time not just current
> platforms. If M$/Apple does something dramatic in a future OS release
> you'll be just as happy that we spent time on it as I want to be now -
> probably more so because you (as in win32 vm) have millions of probably
> screaming users whereas I only have a thousand or two to pacify.

That's why I'm in favour of the simplest model possible ;-)

Cheers,
  - Andreas