Re: Fonts (2) -> problems with GSFontAntiAlias 'YES'

[Fred Kiefer]

Perhaps I should explain a bit more on how the current Anti-Alias font
implementation works and which limitations are caused by this.

This code was a hack that I came up with kust to see if there is any
demand for better fonts in the GNUstep community or if this is only a
low priority addon.
Currently the available fonts are determined by the font cacher using
the standard X font enumeration. This knows nothing about anti-aliasing
and which fonts would support it. Than when a font is selected and AA is
switched on the normal X name of the font is handed on to the AA font
module that tries to create a font for this X name, if it does not find
a suitable AA font it falls back on a standard AA font (or even a simple
X font). SO what would be needed here is a separate font manager for the
AA fonts that would run its own cacher, looking only at AA fonts. This
manager could than know more about the available fonts and select a
better one if the requested is not available.

This should explain your 3. problem and a way to solve it. What it does
not account for is the first problem you are having. For this I will
need some more information. Does this only happen for specific text?
(E.g. some encodings might not be available for the AA fonts) I could
not reproduce this with the standard GNUstep applications.

Cheers
Fred


Pascal Bourguignon wrote:
> 
> > Pascal Bourguignon wrote:
> >
> > > When  I open the  Font Panel,  I get  a list  with about  60 different
> > > fonts.  However,  in  the Preview  they  all  look  the same  but  the
> > > following:
> >
> > I reverted the xgps backend to find fonts by pixel size. Please let me
> > know if anything improves.
> 
> Yes and  no. I updated from CVS  12 yours ago (after  your email), and
> tested  it now.  Here are  the results.  (See attached  window content
> dumps).
> 
> I've found what  produced the bad results I got :  I had the following
> default set: NSGlobalDomain GSFontAntiAlias 'YES'
> 
> When removing it, everything works as expected, I can change the fonts
> and size  with the  corresponding defaults and  I don't get  any black
> rectangle.
> 
> When I have NSGlobalDomain GSFontAntiAlias 'YES' set, then:
> 
> 1/
> 
> It  seems  that  for most  windows,  the  display  of the  text  halts
> halfway.
> 
> For  the  menu,  I've seen  once  when  updating  slowly that  it  had
> transitorily  the  state  of  black  rectangles,  then  the  text  was
> overwritten.
> 
> For the  other windows, when  resizing the window, sometimes  the text
> would appear  and sometimes it  would disappear, but this  state stays
> untile the window is resized again.
> 
> Notably, for the open panel,  whatever navigation is done don't change
> the state black rectangle or  text. Moving the window off-screen, then
> back on-scren does  not change anything. The same  occurs for the Font
> panel. When  I don't get  the black rectangles, it  previews correctly
> the fonts.
> 
> The text in pop-up menus appears correctly.
> 
> It's probably the same bug than  that that don't display pictures in a
> window when not running with a runloop. Note that in that case, moving
> the window off-screen then on-screen would at least show the picture.
> 
> 2/
> 
> The  sizes are  correct.  The  NSFontSize default  is  not taken  into
> account, but the other NS*FontSize are.
> 
> 3/
> 
> The same font  is used everywhere (seems to be Times)  but in the menu
> title.
> 
> Thanks for the font size correction.