Re: dimensions when doing text-scale-increase, and including minibuffer in text-scale-increase

[Eli Zaretskii <eliz@gnu.org>]

> From: Samuel Wales <samologist@gmail.com>
> Date: Tue, 10 Dec 2019 12:28:29 -0700
> 
> question 1:
> 
> if i want to know the usable default dimensions in human lines and
> columns terms, i can do:
> 
> (let ((r (list (frame-width)
>                  (frame-height))))
>     (message "%s =frame width and height =(should be (110 32) at
> /native resolution 1440/ with /dpi of 216/)"
>              r)
> 
> but if i do text-scale-increase the result is the same.

Yes, because frame-width and frame-height return values in units of
the canonical character size.

> i want to know the same data about what is /there now/.

Then use frame-pixel-width and frame-pixel-height, and divide by
default-font-width and default-font-height to get the results in
columns and lines.

> i want to do text-scale increase on exactly the active buffer and
> "its" minibuffer, but not any other buffers.  i'd prefer modeline not
> increase, however.
> 
> whenever i switch back to the increased buffer, i want it and "its"
> echo area / minibuffer to still be increased.

For the echo area and the minibuffer you will have to use hooks,
because switching to another buffer doesn't switch the echo-area or
minibuffer.  IOW, there's no separate echo-area/minibuffer for each
buffer.