Bug#856033: ITP: brailleimg -- produce text images and graphs abusing Braille glyphs

[Samuel Thibault <sthibault@debian.org>]

Adam Borowski, on sam. 25 févr. 2017 18:24:33 +0100, wrote:
> Alas, it won't work: I see that, while alignment of the graph itself works
> well, anything but terminals (which force a char-cell grid) fails to give
> Braille and ASCII characters the same width, despite requesting fixed-width
> display.

That's not normal: fixed-width fonts should really have fixed-width for
the characters used by gnuplot.

> You can see how bad it is on https://angband.pl/doc/alluni.txt -- you should
> get an aligned grid with right edge of every full block forming an even
> vertical line, yet most blocks fail to align even within themselves.

That's expected: some characters have double-width, others have
zero-width. But for characters that have single-width, they are really
aligned with a proper fixed-width font.

> gnuplot relies on being able to place labels within the image, which works
> for ASCII and maybe Latin/Greek/Cyrillic but, except for most terminals, not
> for anything else.

Then gnuplot is missing taking into account the value returned by
wcwidth() (0, 1, 2, ...), that's the bug.

Samuel