EGL_MESA_screen_surface version 5

[Adam Jackson]

On Friday 22 April 2005 14:36, Jon Smirl wrote:
> On 4/22/05, Adam Jackson <ajax at nwnk.net> wrote:
> > The thing is, right now screen_numbers are magic.  The app doesn't have
> > any way of knowing whether a given screen number is valid.  Imagine
> > plugging in screens 0, 1, and 2, and then unplugging 1.  Right now we
> > don't even specify whether screen numbers start at zero or one.  The app
> > has to guess.
>
> Why aren't screen numbers opaque handles? In shared display
> environments with ad hoc networking there might be screens coming and
> going all of the time. Should there instead be an iterator function
> that can handle screens disappearing? We want this API to work ten
> years from now.

This is why I said the semantics are allowed to change in the presence of a 
hotplug extension.  Once you call the EnableHotplug routine that said 
extension defines, then you can change the EGL_SCREEN_COUNT_MESA semantics 
and add API for requesting a new handle, iterating over screens, etc.  But 
it's logically separate, and the implementation is separable from the basic 
stuff we've been talking about.  So we should separate it.  Build 
EGL_MESA_dynamic_screens on top of this extension, once we have an idea how 
it should work.  Let's get MESA_screen_surface to the 90% point so we can 
start building with it.

Remember that EGL will continue to be used on low-end devices.  If you have to 
add all these additional entrypoints and code to support massively dynamic 
screen reconfiguration as a _requirement_ for implementing 
MESA_screen_surface, then it becomes less attractive for small devices.

I don't want to design a hotplug extension right now, but that's just an 
expression of my personal priorities, not a declaration that no one should.  
Feel free to interpret that as a challenge ;).

- ajax
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: not available
Url : http://lists.freedesktop.org/archives/dri-egl/attachments/20050422/c71c9223/attachment.pgp