Re: [Groff] underlining in nroff

[Werner LEMBERG]

> An underlined space is indeed displayed as a space in underlined
> mode.

???  I get different results.  Please look at the attached examples.

  `lesstest.a.cat.png' shows some relevant ISO 6429 escape sequences
  -- xterm is indeed able to display an underlined underscore (this
  works with other X fonts also).

  It looks like a bug concerning underlined tabs in
  `lesstest.b.cat.png' ...

  `lesstest.b.less.png' exhibits a bug in less (which I've already
  reported) with tabs.

> An underlined underscore would be treated the same way, except that
> it just so happens that the bold attribute (overstriking a character
> with itself) takes precedence, so an underscore overstruck with an
> underscore is displayed as an underscore in bold, not underlined.

But I don't get a bold underscore character (compare the bold
underscore in `lesstest.a.cat.png with lesstest.b.less.png').

> Back to (what I think was) the original issue, the problems you're
> seeing are probably a result of different fonts displaying a bold
> underscore differently.

I don't think this is a font issue...


    Werner

lesstest.b.less.png
Description: PNG image

lesstest.b.cat.png
Description: PNG image

lesstest.a.cat.png
Description: PNG image

Spaces between words:

_T_h_i_s_ _i_s_ _a_ _t_e_s_t_.
This is a test.

Tabs between words:

_T_h_i_s_  _i_s_        _a_   _t_e_s_t_.
This    is      a       test.

Underscores between words:

_T_h_i_s___i_s___a___t_e_s_t_.
This_is_a_test.

Here are some tests for the ISO 6429 Set Graphics Rendition command

This is_a test.  0 default rendition
This is_a test.  1 bold or increased intensity
This is_a test.  4 singly underlined