Re: protocol enhancements

On Mon, 24 Mar 2003, David Dawes wrote:

> On Mon, Mar 24, 2003 at 07:23:28AM -0500, Alan Cox wrote:
> >> committed to continuing to work on older X servers, and nobody is
> >> going to go the X12 route (break back compat). So new stuff is always
> >> either a library you can install regardless of your X server
> >> (e.g. fontconfig) or an extension that we use only optionally
> >> (e.g. RENDER).

> >Both Gtk and X11 are going to break horribly in the next few years and
> >there is going to be a need for X.org, XFree or someone to actually fix
> >the standards to allow over 65535 pixels width and height. Otherwise you
> >are not going to be able to run X11 on your walls or on ultra fine
> >resolution displays.

> Absolutely, and I'm glad to see someone else thinking about future
> hardware/technology.  This is an issue I've been trying to get some
> traction on internally, but it has been difficult.  For example,
> the responses I get (from Jim and Keith in particular) are like
> "that's not relevant, and won't be for 5-10 years", and "it will
> break the protocol", etc.  That's very short-sighted.  Xinerama
> with enough high-res screens can come close today (I can never
> remember if the limit is 32767 or 65535).  I'm sure that there'll

As Jim has already pointed out, the limit is 32767.

> be other issues exposed as we start working towards this.  I'd like
> to see at a minimum that the X server internals, and any proposed
> re-writes thereof in the context of 5.0, are prepared for this and
> for deeper and non-integer pixel types.  I also think that bumping
> the protocol minor revision should be explored as a backward-compatible
> mechanism for enhancing the core protocol.  For those who don't
> know, the X11 protocol has a so-far unused provision for a
> client/server protocol handshake, and this type of detail can be
> embedded in Xlib.  There's no need to go to "X12" to do this, or
> to keep tacking on miscellaneous extensions to deal with what are
> core protocol issues.

Extensions have the advantage of allowing for independence.  Also, there's
already a handshake in place:  Client says "Do you support extension XYZ?"
and Server answers yes or no.

Marc.

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