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diff --git a/man/man3/cachechars.html b/man/man3/cachechars.html deleted file mode 100644 index 382b5e7e..00000000 --- a/man/man3/cachechars.html +++ /dev/null @@ -1,292 +0,0 @@ -<head> -<title>cachechars(3) - Plan 9 from User Space</title> -<meta content="text/html; charset=utf-8" http-equiv=Content-Type> -</head> -<body bgcolor=#ffffff> -<table border=0 cellpadding=0 cellspacing=0 width=100%> -<tr height=10><td> -<tr><td width=20><td> -<tr><td width=20><td><b>CACHECHARS(3)</b><td align=right><b>CACHECHARS(3)</b> -<tr><td width=20><td colspan=2> - <br> -<p><font size=+1><b>NAME </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - cachechars, agefont, loadchar, Subfont, Fontchar, Font – font utilities<br> - -</table> -<p><font size=+1><b>SYNOPSIS </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>#include <u.h><br> - #include <libc.h><br> - #include <draw.h> - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <tt><font size=+1>int cachechars(Font *f, char **s, Rune **r, ushort *c, int max, - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>int *widp, char **sfname) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - - </table> - - </table> - <tt><font size=+1>int loadchar(Font *f, Rune r, Cacheinfo *c, int h, - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>int noclr, char **sfname) - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - - </table> - - </table> - <tt><font size=+1>void agefont(Font *f)<br> - </font></tt> -</table> -<p><font size=+1><b>DESCRIPTION </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - A <i>Font</i> may contain too many characters to hold in memory simultaneously. - The graphics library and draw device (see <a href="../man3/draw.html"><i>draw</i>(3)</a>) cooperate to - solve this problem by maintaining a cache of recently used character - images. The details of this cooperation need not be known by most - programs: <i>initdraw</i> and its associated - <i>font</i> variable, <i>openfont</i>, <i>stringwidth</i>, <i>string</i>, and <i>freefont</i> are - sufficient for most purposes. The routines described below are - used internally by the graphics library to maintain the font cache. - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - A <tt><font size=+1>Subfont</font></tt> is a set of images for a contiguous range of characters, - stored as a single image with the characters placed side-by-side - on a common baseline. It is described by the following data structures.<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>typedef<br> - struct Fontchar {<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - int x; /* left edge of bits */<br> - uchar top; /* first non−zero scan−line */<br> - uchar bottom; /* last non−zero scan−line */<br> - char left; /* offset of baseline */<br> - uchar width; /* width of baseline */<br> - - </table> - } Fontchar;<br> - typedef<br> - struct Subfont {<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - char *name;<br> - short n; /* number of chars in subfont */<br> - uchar height; /* height of image */<br> - char ascent; /* top of image to baseline */<br> - Fontchar *info; /* n+1 Fontchars */<br> - Image *bits; /* of font */<br> - - </table> - } Subfont;<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - - </table> - The image fills the rectangle <tt><font size=+1>(0, 0,</font></tt> <i>w</i><tt><font size=+1>, height)</font></tt>, where <i>w</i> is the - sum of the horizontal extents (of non-zero pixels) for all characters. - The pixels to be displayed for character <i>c</i> are in the rectangle - <tt><font size=+1>(</font></tt><i>i</i><tt><font size=+1>−>x,</font></tt> <i>i</i><tt><font size=+1>−>top, (</font></tt><i>i</i><tt><font size=+1>+1)−>x,</font></tt> <i>i</i><tt><font size=+1>−>bottom)</font></tt> where <i>i</i> is <tt><font size=+1>&subfont−>info[</font></tt><i>c</i><tt><font size=+1>]</font></tt>. When - a character is displayed - at <tt><font size=+1>Point p</font></tt> in an image, the character rectangle is placed at <tt><font size=+1>(p.x+</font></tt><i>i</i><tt><font size=+1>−>left, - p.y)</font></tt> and the next character of the string is displayed at <tt><font size=+1>(p.x+</font></tt><i>i</i><tt><font size=+1>−>width, - p.y)</font></tt>. The baseline of the characters is <tt><font size=+1>ascent</font></tt> rows down from - the top of the subfont image. The <tt><font size=+1>info</font></tt> array has <tt><font size=+1>n+1</font></tt> elements, - one each for characters 0 - to <tt><font size=+1>n−1</font></tt> plus an additional entry so the size of the last character - can be calculated. Thus the width, <i>w</i>, of the <tt><font size=+1>Image</font></tt> associated - with a <tt><font size=+1>Subfont s</font></tt> is <tt><font size=+1>s−>info[s−>n].x</font></tt>. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - A <tt><font size=+1>Font</font></tt> consists of an overall height and ascent and a collection - of subfonts together with the ranges of runes (see <a href="../man7/utf.html"><i>utf</i>(7)</a>) they - represent. Fonts are described by the following structures.<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>typedef<br> - struct Cachefont {<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - Rune min; /* value of 0th char in subfont */<br> - Rune max; /* value+1 of last char in subfont */<br> - int offset; /* posn in subfont of char at min */<br> - char *name; /* stored in font */<br> - char *subfontname;/* to access subfont */<br> - - </table> - } Cachefont;<br> - typedef<br> - struct Cacheinfo {<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - ushort x; /* left edge of bits */<br> - uchar width; /* width of baseline */<br> - schar left; /* offset of baseline */<br> - Rune value; /* of char at this slot in cache */<br> - ushort age;<br> - - </table> - } Cacheinfo;<br> - typedef<br> - struct Cachesubf {<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - ulong age; /* for replacement */<br> - Cachefont *cf; /* font info that owns us */<br> - Subfont *f; /* attached subfont */<br> - - </table> - } Cachesubf;<br> - typedef<br> - struct Font {<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - char *name;<br> - Display *display;<br> - short height; /* max ht of image;interline space*/<br> - short ascent; /* top of image to baseline */<br> - short width; /* widest so far; used in caching */<br> - short nsub; /* number of subfonts */<br> - ulong age; /* increasing counter; for LRU */<br> - int ncache; /* size of cache */<br> - int nsubf; /* size of subfont list */<br> - Cacheinfo *cache;<br> - Cachesubf *subf;<br> - Cachefont **sub; /* as read from file */<br> - Image *cacheimage;<br> - - </table> - } Font;<br> - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - </font></tt> - - </table> - The <tt><font size=+1>height</font></tt> and <tt><font size=+1>ascent</font></tt> fields of Font are described in <a href="../man3/graphics.html"><i>graphics</i>(3)</a>. - <tt><font size=+1>Sub</font></tt> contains <tt><font size=+1>nsub</font></tt> pointers to <tt><font size=+1>Cachefonts</font></tt>. A <tt><font size=+1>Cachefont</font></tt> connects - runes <tt><font size=+1>min</font></tt> through <tt><font size=+1>max</font></tt>, inclusive, to the subfont with file name - <tt><font size=+1>name</font></tt>; it corresponds to a line of the file describing the font. - - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - The characters are taken from the subfont starting at character - number <tt><font size=+1>offset</font></tt> (usually zero) in the subfont, permitting selection - of parts of subfonts. Thus the image for rune <i>r</i> is found in position - <i>r</i><tt><font size=+1>−min+offset</font></tt> of the subfont. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - For each font, the library, with support from the graphics server, - maintains a cache of subfonts and a cache of recently used character - images. The <tt><font size=+1>subf</font></tt> and <tt><font size=+1>cache</font></tt> fields are used by the library to maintain - these caches. The <tt><font size=+1>width</font></tt> of a font is the maximum of the horizontal - extents of the characters in the cache. - <i>String</i> draws a string by loading the cache and emitting a sequence - of cache indices to draw. <i>Cachechars</i> guarantees the images for - the characters pointed to by <i>*s</i> or <i>*r</i> (one of these must be nil - in each call) are in the cache of <i>f</i>. It calls <i>loadchar</i> to put - missing characters into the cache. <i>Cachechars</i> translates the - character string into a set of cache indices which it loads into - the array <i>c</i>, up to a maximum of <i>n</i> indices or the length of the - string. <i>Cachechars</i> returns in <i>c</i> the number of cache indices emitted, - updates <i>*s</i> to point to the next character to be processed, and - sets <i>*widp</i> to the total width of the characters processed. - <i>Cachechars</i> may return before the end of the string if it cannot - proceed without destroying active data in the caches. If it needs - to load a new subfont, it will fill <tt><font size=+1>*sfname</font></tt> with the name of the - subfont it needs and return –1. It can return zero if it is unable - to make progress because it cannot resize the caches. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - <i>Loadchar</i> loads a character image into the character cache. Then - it tells the graphics server to copy the character into position - <i>h</i> in the character cache. If the current font <tt><font size=+1>width</font></tt> is smaller - than the horizontal extent of the character being loaded, <i>loadfont</i> - clears the cache and resets it to accept characters with the - bigger width, unless <i>noclr</i> is set, in which case it just returns - –1. If the character does not exist in the font at all, <i>loadfont</i> - returns 0; if it is unable to load the character without destroying - cached information, it returns –1, updating <tt><font size=+1>*sfname</font></tt> as described - above. It returns 1 to indicate success. - <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> - - The <tt><font size=+1>age</font></tt> fields record when subfonts and characters have been used. - The font <tt><font size=+1>age</font></tt> is increased every time the font is used (<i>agefont</i> - does this). A character or subfont <tt><font size=+1>age</font></tt> is set to the font age - at each use. Thus, characters or subfonts with small ages are - the best candidates for replacement when the cache is full. - -</table> -<p><font size=+1><b>SOURCE </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <tt><font size=+1>/usr/local/plan9/src/libdraw<br> - </font></tt> -</table> -<p><font size=+1><b>SEE ALSO </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - <a href="../man3/graphics.html"><i>graphics</i>(3)</a>, <a href="../man3/allocimage.html"><i>allocimage</i>(3)</a>, <a href="../man3/draw.html"><i>draw</i>(3)</a>, <a href="../man3/subfont.html"><i>subfont</i>(3)</a>, <a href="../man7/image.html"><i>image</i>(7)</a>, <a href="../man7/font.html"><i>font</i>(7)</a><br> - -</table> -<p><font size=+1><b>DIAGNOSTICS </b></font><br> - -<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> - - All of the functions use the graphics error function (see <a href="../man3/graphics.html"><i>graphics</i>(3)</a>).<br> - -</table> - -<td width=20> -<tr height=20><td> -</table> -<!-- TRAILER --> -<table border=0 cellpadding=0 cellspacing=0 width=100%> -<tr height=15><td width=10><td><td width=10> -<tr><td><td> -<center> -<a href="../../"><img src="../../dist/spaceglenda100.png" alt="Space Glenda" border=1></a> -</center> -</table> -<!-- TRAILER --> -</body></html> |