Am 25.04.2021 um 15:41 schrieb Lemures Lemniscati via Cygwin:
Hi!
mintty overstrokes some fonts unexpectedly.
https://gitlab.com/test.cases/mintty-test/-/tree/54ae800e695ecd1741851cab57320a9d0e95a6fd
How to reproduce
Setting mintty to use msgothic.ttc in 20pt, run a
following command.
====
perl -e '
binmode STDOUT, ":utf8";
print <<END;
01234567
\x{3042}\x{3044}\x{3046}\x{3048}
AaBbCcDe
\x{25cb}\x{25cb}\x{25cb}\x{25cb}
\x{3007}\x{3007}\x{3007}\x{3007}
\x{300c}\x{300e}\x{3010}\x{3012}
\x{300d}\x{300f}\x{3011}\x{3013}
\x{ff62}\x{ff63}\x{ff62}\x{ff63}\x{ff62}\x{ff63}\x{ff62}\x{ff63}
\x{ff71}\x{ff72}\x{ff73}\x{ff74}\x{ff75}\x{ff76}\x{ff77}\x{ff78}
END
'
====
I got a result mintty-sample-msgothic.png.
https://gitlab.com/test.cases/mintty-test/-/blob/54ae800e695ecd1741851cab57320a9d0e95a6fd/mintty-sample-msgothic.png
In the 4th line of the output, fonts (of u+25cb) were overstruck
unexpectedly.
And there are other characters also, which are similarly overstruck.
This is a Windows bug. Mintty clearly instruct Windows to apply
equidistant spacing to achieve fixed-width character cell behaviour. But
for certain character ranges, Windows ignores that. Another example for
such misbehaviour is the Tibetan block (U+0F00-U+0FFF). Mintty could
work around that by rendering characters separately, at a significant
penalty for output speed however. Or it could do that only for affected
ranges, but criteria to identify them are obscure.
Thomas
--
Problem reports: https://cygwin.com/problems.html
FAQ: https://cygwin.com/faq/
Documentation: https://cygwin.com/docs.html
Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
