> From: Kenichi Handa <handa@m17n...>
> Cc: emacs-bidi@gnu...., emacs-devel@gnu.... > Date: Mon, 01 Nov 2010 20:16:57 +0900
> And, for tty, as it's impossible to do the same thing as
> graphic terminal, the current code does this:
> thin-space: same as empty-box
> hexa-code: display "U+XX", "U+XXXX", "U+XXXXXX" ,
> "E+XXXXXX" depends on the character code (the last
> one is for a character of code >= #x110000).
> acronym: surround an acronym by "[" and "]" as this:
> "[ZWNJ]", "[LRE]"
> At the moment, that is hardcoded in the function
> produce_glyphless_glyph of term.c.
> And, for tty, `no-font' means a character not encodable by
> the terminal coding system.
There are a few issues that perhaps need to be fixed:
. If the default value of terminal-coding-system is nil, glyphless
character display does not take effect: all the non-ASCII
characters are displayed as question marks. I think this is
because safe_terminal_coding claims it can safely encode any
character. This look inconsistent and confusing, so I think we
should fix that.
. Composite characters are displayed as question marks regardless of
the setting of glyphless-char-display-control. I think this is
because term.c:produce_composite_glyph does not consider the new
glyphless-char display feature. I think users will expect that
composite characters behave like un-encodable characters on a TTY.