[PATCHv3] Add name event to xdg-output

[Drew DeVault]

On 2018-04-13  4:16 PM, Jonas Ådahl wrote:
> If that is the case, I'd rather we introduced data that has actual
> meaning, like something similar to "connector" (even though connector is
> the wrong thing here since an "xdg_output" might not have one, maybe,
> something that doesn't identify the monitor itself, but how it is
> connected, if that is what you want) and then a different thing that is
> more meaningful to a user interface. Then whether the "this is string is
> user interface facing" should have anything to do with where the wire is
> plugged in or what is actually plugged in can be up to the software that
> is responsible for generating that string, but it should be clear what
> its purpose is.

This has already been discussed in the rest of the thread. We would have
to add meaning that isn't necessarily there. The meaning is deliberately
omitted. There are many cases we can suppose that make it difficult to
add any meaning. Instead of adding meaning, we make guarantees.

We have two audiences we need to communicate with: the client, and the
end-user. They have different needs.

The end-user only needs to be able to select an output using terminology
they will understand. We can trust compositor implementors to embue
these names with the right amount of meaning for this purpose and
to educate their users on their approach. All the client has to do to
fulfill this is faithfully communicate the name the compositor has
provided to the user.

The client needs to:

1. Provide the user a means to select an output in terms they will
   understand
2. Identify outputs across sessions

Any knowledge of the inputs that went into preparing the name are not
among the supported use-cases of this protocol. It's not important for
the client to understand that. They just need these two needs fulfilled.

To that end, rather than making a futile attempt to describe outputs in
terms that won't apply in all cases, the current revision aims only to
secure these two guarantees.

--
Drew DeVault