Re: Boxes not boxed in the header-line

[Stefan Monnier]

> That is a subtle distinction, and I am not sure it changes anything.
> Does it make sense to have a box with a 3d effect inside a line with a
> 3d effect?

Yes: at least my original example makes perfect sense to me.

>     The 3d effect used for the buttons in SES mode makes sense in isolation.
>     The 3d effect used on the header-line makes sense in isolation as well.
>     The combination of the two is mostly out of the user's control.

> I don't understand the last sentence.  Could you explain the situation
> that causes these two things to occur together?

The way the are combined is not by having the user say "I want a 3d
header-line and 3d SES boxes", but only "I want a 3d header-line and I want
to use SES".

A 3d header-line makes perfect sense (that's what I use and it was Emacs's
default at some point during its development IIRC) since it makes it look
more like a kind of mode-line and thus makes it more obvious that it's not
part of the buffer text.

>> The reason it seems nonsensical to me is that it seems to involve
>> 3-d boxes inside 3-d boxes.

>     I think the wy to make sense of it is the following:

>     - outside of 3d boxes, the thickness is 0.

>     - raised thickness is positive, depressed thickness is negative.

> Sorry, I am lost.  What does "thickness" mean?

Sorry, I got my terminology wrong.  It's called ":line-width".

> What does it mean for the thickness to be negative or positive?

The above text defines its meaning.  It means nothing more.

>     - when moving from thickness 0 to thickness N (or -N), we currently
>     insert a N-pixel wide line (either light or dark).

>     - so when moving from thickness 1 to thickness 2, we should insert
>     a 1-pixel wide line, and when moving from thickness -2 to thickness
>     1 we should insert a 3-pixel wide line.

> I don't entirely understand that, but if it affects only the cases
> that now look bad, and makes them look better.

That's the intention.


        Stefan