Re: Emacs 23, so slow to refresh on Windows

[bogossian]

> Assuming you use continuation lines, and not truncation, does the
> speed improve setting `cache-long-line-scans' to t? (Note that the
> variable is automatically buffer-local, so be sure to set it in the
> appropriate buffer, or use setq-default.)

Setting this variable doesn't make a noticeable difference.
For instance, scrolling through a 200k csv file made of 200 lines of 
1000
characters each, feels just as choppy whether the cache is enabled or 
not.

> Yes, I think so. You can see the backend used for a font by moving the
> cursor over a character in that font and doing "C-u C-x =". The font
> information will start with gdi: or uniscribe:

As expected the gdi backend is used:

       character: D (68, #o104, #x44)
preferred charset: ascii (ASCII (ISO646 IRV))
      code point: 0x44
          syntax: w    which means: word
        category: .:Base, a:ASCII, l:Latin, r:Roman
     buffer code: #x44
       file code: #x44 (encoded by coding system undecided-dos)
         display: by this font (glyph code)
    gdi:-raster-6X13-normal-normal-normal-*-13-*-*-*-c-*-iso8859-1 
(#x44)

Character code properties: customize what to show
 name: LATIN CAPITAL LETTER D
 general-category: Lu (Letter, Uppercase)

BTW, 6x13 is not the only font for which I noticed these extremely bad
performances. The bitmap version of the courier font (which I think is
installed by default with Windows XP) exhibits the same slowdown.
So it should be easy for you to reproduce the problem using this font.

       character: D (68, #o104, #x44)
preferred charset: ascii (ASCII (ISO646 IRV))
      code point: 0x44
          syntax: w    which means: word
        category: .:Base, a:ASCII, l:Latin, r:Roman
     buffer code: #x44
       file code: #x44 (encoded by coding system undecided-dos)
         display: by this font (glyph code)
    
gdi:-raster-Courier-normal-normal-normal-mono-13-*-*-*-c-*-iso8859-1 
(#x44)

Character code properties: customize what to show
 name: LATIN CAPITAL LETTER D
  general-category: Lu (Letter, Uppercase)