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   1  Bitstream Vera Fonts - April 16, 2003
   2  =====================================
   3  
   4  The version number of these fonts is 1.10 to distinguish them from the
   5  beta test fonts.
   6  
   7  Note that the Vera copyright is incorporated in the fonts themselves.
   8  The License field in the fonts contains the copyright license as it
   9  appears below. The TrueType copyright field is not large enough to
  10  contain the full license, so the license is incorporated (as you might
  11  think if you thought about it) into the license field, which
  12  unfortunately can be obscure to find.  (In pfaedit, see: Element->Font
  13  Info->TTFNames->License).
  14  
  15  Our apologies for it taking longer to complete the fonts than planned.
  16  Beta testers requested a tighter line spacing (less leading) and Jim
  17  Lyles redesigned Vera's accents to bring its line spacing to more
  18  typical of other fonts.  This took additional time and effort.  Our
  19  thanks to Jim for this effort above and beyond the call of duty.
  20  
  21  There are four monospace and sans faces (normal, oblique, bold, bold
  22  oblique) and two serif faces (normal and bold). Fontconfig/Xft2 (see
  23  www.fontconfig.org) can artificially oblique the serif faces for you:
  24  this loses hinting and distorts the faces slightly, but is visibly
  25  different than normal and bold, and reasonably pleasing.
  26  
  27  On systems with fontconfig 2.0 or 2.1 installed, making your sans,
  28  serif and monospace fonts default to these fonts is very easy.  Just
  29  drop the file local.conf into your /etc/fonts directory.  This will
  30  make the Bitstream fonts your default fonts for all applications using
  31  fontconfig (if sans, serif, or monospace names are used, as they often
  32  are as default values in many desktops). The XML in local.conf may
  33  need modification to enable subpixel decimation, if appropriate,
  34  however, the commented out phrase does so for XFree86 4.3, in the case
  35  that the server does not have sufficient information to identify the
  36  use of a flat panel.  Fontconfig 2.2 adds Vera to the list of font
  37  families and will, by default use it as the default sans, serif and
  38  monospace fonts.
  39  
  40  During the testing of the final Vera fonts, we learned that screen
  41  fonts in general are only typically hinted to work correctly at
  42  integer pixel sizes.  Vera is coded internally for integer sizes only.
  43  We need to investigate further to see if there are commonly used fonts
  44  that are hinted to be rounded but are not rounded to integer sizes due
  45  to oversights in their coding.
  46  
  47  Most fonts work best at 8 pixels and below if anti-aliased only, as
  48  the amount of work required to hint well at smaller and smaller sizes
  49  becomes astronomical.  GASP tables are typically used to control
  50  whether hinting is used or not, but Freetype/Xft does not currently
  51  support GASP tables (which are present in Vera).
  52  
  53  To mitigate this problem, both for Vera and other fonts, there will be
  54  (very shortly) a new fontconfig 2.2 release that will, by default not
  55  apply hints if the size is below 8 pixels. if you should have a font
  56  that in fact has been hinted more agressively, you can use fontconfig
  57  to note this exception. We believe this should improve many hinted
  58  fonts in addition to Vera, though implemeting GASP support is likely
  59  the right long term solution.
  60  
  61  Font rendering in Gnome or KDE is the combination of algorithms in
  62  Xft2 and Freetype, along with hinting in the fonts themselves. It is
  63  vital to have sufficient information to disentangle problems that you
  64  may observe.
  65  
  66  Note that having your font rendering system set up correctly is vital
  67  to proper judgement of problems of the fonts:
  68  
  69      * Freetype may or may not be configured to in ways that may
  70        implement execution of possibly patented (in some parts of the world)
  71        TrueType hinting algorithms, particularly at small sizes.  Best
  72        results are obtained while using these algorithms.
  73  
  74      * The freetype autohinter (used when the possibly patented
  75        algorithms are not used) continues to improve with each release. If
  76        you are using the autohinter, please ensure you are using an up to
  77        date version of freetype before reporting problems.
  78  
  79      * Please identify what version of freetype you are using in any
  80        bug reports, and how your freetype is configured.
  81  
  82      * Make sure you are not using the freetype version included in
  83        XFree86 4.3, as it has bugs that significantly degrade most fonts,
  84        including Vera. if you build XFree86 4.3 from source yourself, you may
  85        have installed this broken version without intending it (as I
  86        did). Vera was verified with the recently released Freetype 2.1.4. On
  87        many systems, 'ldd" can be used to see which freetype shared library
  88        is actually being used.
  89  
  90      * Xft/X Render does not (yet) implement gamma correction.  This
  91        causes significant problems rendering white text on a black background
  92        (causing partial pixels to be insufficiently shaded) if the gamma of
  93        your monitor has not been compensated for, and minor problems with
  94        black text on a while background.  The program "xgamma" can be used to
  95        set a gamma correction value in the X server's color pallette. Most
  96        monitors have a gamma near 2.
  97  
  98      * Note that the Vera family uses minimal delta hinting. Your
  99        results on other systems when not used anti-aliased may not be
 100        entirely satisfying. We are primarily interested in reports of
 101        problems on open source systems implementing Xft2/fontconfig/freetype
 102        (which implements antialiasing and hinting adjustements, and
 103        sophisticated subpixel decimation on flatpanels).  Also, the
 104        algorithms used by Xft2 adjust the hints to integer widths and the
 105        results are crisper on open source systems than on Windows or
 106        MacIntosh.
 107  
 108      * Your fontconfig may (probably does) predate the release of
 109        fontconfig 2.2, and you may see artifacts not present when the font is
 110        used at very small sizes with hinting enabled. "vc-list -V" can be
 111        used to see what version you have installed.
 112  
 113  We believe and hope that these fonts will resolve the problems
 114  reported during beta test.  The largest change is the reduction of
 115  leading (interline spacing), which had annoyed a number of people, and
 116  reduced Vera's utility for some applcations.  The Vera monospace font
 117  should also now make '0' and 'O' and '1' and 'l' more clearly
 118  distinguishable.
 119  
 120  The version of these fonts is version 1.10.  Fontconfig should be
 121  choosing the new version of the fonts if both the released fonts and
 122  beta test fonts are installed (though please discard them: they have
 123  names of form tt20[1-12]gn.ttf).  Note that older versions of
 124  fontconfig sometimes did not rebuild their cache correctly when new
 125  fonts are installed: please upgrade to fontconfig 2.2. "fc-cache -f"
 126  can be used to force rebuilding fontconfig's cache files.
 127  
 128  If you note problems, please send them to fonts at gnome dot org, with
 129  exactly which face and size and unicode point you observe the problem
 130  at. The xfd utility from XFree86 CVS may be useful for this (e.g. "xfd
 131  -fa sans").  A possibly more useful program to examine fonts at a
 132  variety of sizes is the "waterfall" program found in Keith Packard's
 133  CVS.
 134  
 135          $ cvs -d :pserver:anoncvs@keithp.com:/local/src/CVS login
 136          Logging in to :pserver:anoncvs@keithp.com:2401/local/src/CVS
 137          CVS password: <hit return>
 138          $ cvs -d :pserver:anoncvs@keithp.com:/local/src/CVS co waterfall
 139          $ cd waterfall
 140          $ xmkmf -a
 141          $ make
 142          # make install
 143          # make install.man
 144  
 145  Again, please make sure you are running an up-to-date freetype, and
 146  that you are only examining integer sizes.
 147  
 148  Reporting Problems
 149  ==================
 150  
 151  Please send problem reports to fonts at gnome org, with the following
 152  information:
 153  
 154     1. Version of Freetype, Xft2 and fontconfig
 155     2. Whether TT hinting is being used, or the autohinter
 156     3. Application being used
 157     4. Character/Unicode code point that has problems (if applicable)
 158     5. Version of which operating system
 159     6. Please include a screenshot, when possible.
 160  
 161  Please check the fonts list archives before reporting problems to cut
 162  down on duplication.