基于SDL的界面框架（组件全面）

Bitstream Vera Fonts - April 16, 2003 ===================================== The version number of these fonts is 1.10 to distinguish them from the beta test fonts. Note that the Vera copyright is incorporated in the fonts themselves. The License field in the fonts contains the copyright license as it appears below. The TrueType copyright field is not large enough to contain the full license, so the license is incorporated (as you might think if you thought about it) into the license field, which unfortunately can be obscure to find. (In pfaedit, see: Element->Font Info->TTFNames->License). Our apologies for it taking longer to complete the fonts than planned. Beta testers requested a tighter line spacing (less leading) and Jim Lyles redesigned Vera's accents to bring its line spacing to more typical of other fonts. This took additional time and effort. Our thanks to Jim for this effort above and beyond the call of duty. There are four monospace and sans faces (normal, oblique, bold, bold oblique) and two serif faces (normal and bold). Fontconfig/Xft2 (see www.fontconfig.org) can artificially oblique the serif faces for you: this loses hinting and distorts the faces slightly, but is visibly different than normal and bold, and reasonably pleasing. On systems with fontconfig 2.0 or 2.1 installed, making your sans, serif and monospace fonts default to these fonts is very easy. Just drop the file local.conf into your /etc/fonts directory. This will make the Bitstream fonts your default fonts for all applications using fontconfig (if sans, serif, or monospace names are used, as they often are as default values in many desktops). The XML in local.conf may need modification to enable subpixel decimation, if appropriate, however, the commented out phrase does so for XFree86 4.3, in the case that the server does not have sufficient information to identify the use of a flat panel. Fontconfig 2.2 adds Vera to the list of font families and will, by default use it as the default sans, serif and monospace fonts. During the testing of the final Vera fonts, we learned that screen fonts in general are only typically hinted to work correctly at integer pixel sizes. Vera is coded internally for integer sizes only. We need to investigate further to see if there are commonly used fonts that are hinted to be rounded but are not rounded to integer sizes due to oversights in their coding. Most fonts work best at 8 pixels and below if anti-aliased only, as the amount of work required to hint well at smaller and smaller sizes becomes astronomical. GASP tables are typically used to control whether hinting is used or not, but Freetype/Xft does not currently support GASP tables (which are present in Vera). To mitigate this problem, both for Vera and other fonts, there will be (very shortly) a new fontconfig 2.2 release that will, by default not apply hints if the size is below 8 pixels. if you should have a font that in fact has been hinted more agressively, you can use fontconfig to note this exception. We believe this should improve many hinted fonts in addition to Vera, though implemeting GASP support is likely the right long term solution. Font rendering in Gnome or KDE is the combination of algorithms in Xft2 and Freetype, along with hinting in the fonts themselves. It is vital to have sufficient information to disentangle problems that you may observe. Note that having your font rendering system set up correctly is vital to proper judgement of problems of the fonts: * Freetype may or may not be configured to in ways that may implement execution of possibly patented (in some parts of the world) TrueType hinting algorithms, particularly at small sizes. Best results are obtained while using these algorithms. * The freetype autohinter (used when the possibly patented algorithms are not used) continues to improve with each release. If you are using the autohinter, please ensure you are using an up to date version of freetype before reporting problems. * Please identify what version of freetype you are using in any bug reports, and how your freetype is configured. * Make sure you are not using the freetype version included in XFree86 4.3, as it has bugs that significantly degrade most fonts, including Vera. if you build XFree86 4.3 from source yourself, you may have installed this broken version without intending it (as I did). Vera was verified with the recently released Freetype 2.1.4. On many systems, 'ldd" can be used to see which freetype shared library is actually being used. * Xft/X Render does not (yet) implement gamma correction. This causes significant problems rendering white text on a black background (causing partial pixels to be insufficiently shaded) if the gamma of your monitor has not been compensated for, and minor problems with black text on a while background. The program "xgamma" can be used to set a gamma correction value in the X server's color pallette. Most monitors have a gamma near 2. * Note that the Vera family uses minimal delta hinting. Your results on other systems when not used anti-aliased may not be entirely satisfying. We are primarily interested in reports of problems on open source systems implementing Xft2/fontconfig/freetype (which implements antialiasing and hinting adjustements, and sophisticated subpixel decimation on flatpanels). Also, the algorithms used by Xft2 adjust the hints to integer widths and the results are crisper on open source systems than on Windows or MacIntosh. * Your fontconfig may (probably does) predate the release of fontconfig 2.2, and you may see artifacts not present when the font is used at very small sizes with hinting enabled. "vc-list -V" can be used to see what version you have installed. We believe and hope that these fonts will resolve the problems reported during beta test. The largest change is the reduction of leading (interline spacing), which had annoyed a number of people, and reduced Vera's utility for some applcations. The Vera monospace font should also now make '0' and 'O' and '1' and 'l' more clearly distinguishable. The version of these fonts is version 1.10. Fontconfig should be choosing the new version of the fonts if both the released fonts and beta test fonts are installed (though please discard them: they have names of form tt20[1-12]gn.ttf). Note that older versions of fontconfig sometimes did not rebuild their cache correctly when new fonts are installed: please upgrade to fontconfig 2.2. "fc-cache -f" can be used to force rebuilding fontconfig's cache files. If you note problems, please send them to fonts at gnome dot org, with exactly which face and size and unicode point you observe the problem at. The xfd utility from XFree86 CVS may be useful for this (e.g. "xfd -fa sans"). A possibly more useful program to examine fonts at a variety of sizes is the "waterfall" program found in Keith Packard's CVS. $ cvs -d :pserver:[email protected]:/local/src/CVS login Logging in to :pserver:[email protected]:2401/local/src/CVS CVS password: <hit return> $ cvs -d :pserver:[email protected]:/local/src/CVS co waterfall $ cd waterfall $ xmkmf -a $ make # make install # make install.man Again, please make sure you are running an up-to-date freetype, and that you are only examining integer sizes. Reporting Problems ================== Please send problem reports to fonts at gnome org, with the following information: 1. Version of Freetype, Xft2 and fontconfig 2. Whether TT hinting is being used, or the autohinter 3. Application being used 4. Character/Unicode code point that has problems (if applicable) 5. Version of which operating system 6. Please include a screensh