bug#53478: 26.3; Document text-terminal (non)support of pixel-relevant features

bug#53478: 26.3; Document text-terminal (non)support of pixel-relevant features

[Drew Adams]

I tried to help with this user question:

https://emacs.stackexchange.com/q/70231/105

I'm no expert on this.  I guessed that Emacs in terminal mode can't
support most pixel-level operations.

I wanted to point the user to the Emacs manual about this.  I tried to
find info about it with `i' using keyword `terminal' (even with
substring matching for completions).  I found nothing.  Likewise, with
keyword `pixel'.

I then used `C-s' to search the manual for `terminal', with no luck.  I
then tried searching the manual for `pixel'.  The only relevant info I
found was Glossary entry Text Terminal.

Assuming I just searched poorly, please consider adding some index
entries for this information.  If the info is missing, apart from that
caveat in the Glossary, please consider adding some relevant info.

In GNU Emacs 26.3 (build 1, x86_64-w64-mingw32)
 of 2019-08-29
Repository revision: 96dd0196c28bc36779584e47fffcca433c9309cd
Windowing system distributor `Microsoft Corp.', version 10.0.19043
Configured using:
 `configure --without-dbus --host=x86_64-w64-mingw32
 --without-compress-install 'CFLAGS=-O2 -static -g3''

bug#53478: 26.3; Document text-terminal (non)support of pixel-relevant features

[Eli Zaretskii]

> From: Drew Adams <drew.adams@oracle.com>
> Date: Sun, 23 Jan 2022 16:25:12 +0000
> 
> I tried to help with this user question:
> 
> https://emacs.stackexchange.com/q/70231/105
> 
> I'm no expert on this.  I guessed that Emacs in terminal mode can't
> support most pixel-level operations.

That question has nothing to do with pixel-level operations.  It asks
about functions like x-display-pixel-width that are not available in a
build --without-x.

> I wanted to point the user to the Emacs manual about this.  I tried to
> find info about it with `i' using keyword `terminal' (even with
> substring matching for completions).  I found nothing.  Likewise, with
> keyword `pixel'.

I see no reason to say in the manual anything about this that we don't
already do.  Every place that talks about pixels either says it's
relevant to graphical displays, or discusses stiff that is only
relevant to GUI.  The doc string of x-display-pixel-width, for
example, says:

  Return the width in pixels of the X display TERMINAL.
                                    ^^^^^^^^^
So I don't think we should do anything here, and I'm closing this bug
report.