🚀 go-pugleaf

In article <C0CEJ7.102@news.cso.uiuc.edu> amead@s.psych.uiuc.edu (Alan Mead) writes:
>I redefined some text mode characters.  One is like ASCII 196 (a long
>"hyphen" that stretchs the length of the character cell) but is
>supposed to occupy only the bottom row of the definition (unlike 196
>which, roughly, lies on the middle row).
>
>But one of the end columns won't display--resulting in a dashed, instead
>of solid, line when I write a string of these.
>
>I dimly recall that only certain charcters can be defined as line
>characters, but I've tried redefining 184, 189, and 190 and none of
>them work.
>
>Thnaks for any help.
>
>-alan mead


One quick addendum, then (hopefully) an answer.  The dashed output only occurs
on a VGA.  The VGA has a 9x16 character size, while EGA has 8x14.  Since
you're using the bottom of the character, though, it probably won't be visible
at all on an EGA, so it's probably academic.

On a VGA, certain characters are special, as you surmised.  Those characters
have the following property:  if the 8th pixel is on, the ninth for that row
is also on.  The characters you can choose from are: 192-216, 218-220, and 223
(ASCII).  These are the line draw characters which go all the way to the right
hand side.  Sorry if I missed any.  By the way, if anyone knows of a way to
add to the list of these, please post.
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