Re: How does Emacs render glyphs?

[Po Lu <luangruo@yahoo.com>]

Eli Zaretskii <eliz@gnu.org> writes:

>> Date: Sun, 24 Nov 2024 16:03:29 +0100 (CET)
>> From: Roland Lutz <rlutz@hedmen.org>
>> 
>> Hi,
>> 
>> I've been fiddling with Pango text rendering and noticed that the output 
>> looks kind of weird.  Using the same font and size, glyphs rendered via 
>> Pango appear to be one pixel shorter and slightly narrower than in Emacs:
>> 
>> https://hedmen.org/vera-11-emacs.png
>> https://hedmen.org/vera-11-pango.png
>> 
>> Since I very much prefer the way Emacs renders text, I'd like to replicate 
>> this behavior.  Do I assume correctly that Emacs uses Pango internally? 
>
> No, I don't think Emacs uses Pango, at least not directly.  Emacs
> built with Cairo might use Pango indirectly; all the other
> configurations AFAIK do not.
>
> Po Lu, please correct me if I'm wrong.

No, Emacs doesn't use Pango.  The discrepancy observed by the OP is
probably the product of inconsistencies between either hinting or glyph
metrics rounding (but it's hard to say from this description who is in
the wrong).