[compiz] Re: input transformations

[David Reveman]

On Mon, 2007-02-05 at 18:06 -0800, Keith Packard wrote:
> On Mon, 2007-02-05 at 20:04 -0500, David Reveman wrote:
> 
> > From the talks keithp has given on the subject I've understood that
> > implementing this properly is very hard, if not impossible. Is that not
> > the case anymore?
> 
> The hard part was making it asynchronous and routing it through the X
> protocol itself. I did a small fraction of that implementation before
> abandoning it. Creating a synchronous back-channel would work, although
> I have concerns about performance in that case.

Thanks for the explanation, I remember now. Deron, are you using a
synchronous back-channel for LG then? I would also be very concerned
about the performance in that case, how is it working for you?

I guess it might make sense to support both a tri-mesh and an external
picker approach. Most of the dix changes to support either approach
should be the same.

> 
> > Non-contiguous windows are important so I wouldn't want an
> > implementation that didn't support that. It didn't add any complexity to
> > support it in my implementation but I can't be 100% sure of that yet as
> > it's not fully complete though.
> 
> Yeah, I can't imagine that will be all that complicated. How about the
> ability to map from multiple representations of the same window?

Yes, that works fine too and I haven't seen any potential issues with it
yet.

- David