Re: XFree86 5.0 TODO

Sven Luther writes:
 > > This depends. The driver could also provide a short descritive string.
 > > An application not knowing the attribute could just display this
 > > string. Also knowing the type and range of the attribute's variable
 > > it has every information to display a suitable wiget element.
 > > I agree that there is still the i18n issue. But if the string
 > > cannot be found in a translation table it is better to display
 > > an English  string in US-ASCII than nothing.
 > 
 > This would only work if there was some kind of standardization, i am

Yes, I'm planning to have a registry. Haven't I said so?

 > sure that many drivers have different options for the exact same thing.
 > Just being able to extend it is not enough, and if no app support it,
 > then there is no use implementing it.

Sure. What do you want to have? An app that uses an extension that
doesn't exist? Or an extension that offers an API? The idea behind
the thing is: Your App doesn't have to know about the specific
features. It gets enough information to use the right GUI elements
and add a meaningful text to it.
If the app wants more it can implement all attributes that are in
the registry with fancy pictures. However it is forward and backward
compatible: The app doesn't have to know about a certain attribute
to offer you meaningful controls.

 > 
 > Yes, almost all of them in fact, but again, all drivers need to use the
 > same set of keywords, and apps need to actually use it.
 > 
I'm pretty sure that seconds after the API is published people will
start to implement the user interface in their GUI environment.
The good thing is: To start implementing you don't need to know
about the attributes and still have a fully functional interface.
You can add this as the attributes start appearing in the registry.
But the good thing is: if a new attribute comes along the application
doesn't know about yet it can still give you a meaningful interface.


 > > I don't only think about video output drivers but also input drivers.
 > > So there always may be some attribute you want which doesn't exist.
 > 
 > Mmm, actually we are maybe speaking about two different things. I think
 > your work is only to pass the attributes to the drivers from the app,
 > but i was more thinking about a set of functionality that the drivers
 > provide.

Yes.
 > 
 > For example, i don't think you can implement the windows zooming thingy
 > with what you propose. that his, have one viewport/monitor be a zoomed
 > version of a window, even if we move or resize the window.
 > 

There are a lot of other things involved: The driver has no notion
about windows. You'd have to know the window coordinates which can
be queried by the application. The application then has to pass the
coordinates (x,y,w,h) to the extension. With Xinerama we would
have to do some juggling, though.
This should work too with what I propose. Your application just
whould have to query for a certain attribute that is hopefully
registered.
A generic interface that is not aware of the nature of this attribute
would just give you slider elements for (x,y,w,h) so you can set
your coordinates by hand. A little clumbsy but it should work.

Egbert.