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1 /***************************************************************************/
2 /*                                                                         */
3 /*  tttables.h                                                             */
4 /*                                                                         */
5 /*    Basic SFNT/TrueType tables definitions and interface                 */
6 /*    (specification only).                                                */
7 /*                                                                         */
8 /*  Copyright 1996-2001, 2002, 2003, 2004, 2005, 2008, 2009 by             */
9 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
10 /*                                                                         */
11 /*  This file is part of the FreeType project, and may only be used,       */
12 /*  modified, and distributed under the terms of the FreeType project      */
13 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
14 /*  this file you indicate that you have read the license and              */
15 /*  understand and accept it fully.                                        */
16 /*                                                                         */
17 /***************************************************************************/
18 
19 
20 #ifndef __TTTABLES_H__
21 #define __TTTABLES_H__
22 
23 
24 #include <ft2build.h>
25 #include FT_FREETYPE_H
26 
27 #ifdef FREETYPE_H
28 #error "freetype.h of FreeType 1 has been loaded!"
29 #error "Please fix the directory search order for header files"
30 #error "so that freetype.h of FreeType 2 is found first."
31 #endif
32 
33 
34 FT_BEGIN_HEADER
35 
36   /*************************************************************************/
37   /*                                                                       */
38   /* <Section>                                                             */
39   /*    truetype_tables                                                    */
40   /*                                                                       */
41   /* <Title>                                                               */
42   /*    TrueType Tables                                                    */
43   /*                                                                       */
44   /* <Abstract>                                                            */
45   /*    TrueType specific table types and functions.                       */
46   /*                                                                       */
47   /* <Description>                                                         */
48   /*    This section contains the definition of TrueType-specific tables   */
49   /*    as well as some routines used to access and process them.          */
50   /*                                                                       */
51   /*************************************************************************/
52 
53 
54   /*************************************************************************/
55   /*                                                                       */
56   /* <Struct>                                                              */
57   /*    TT_Header                                                          */
58   /*                                                                       */
59   /* <Description>                                                         */
60   /*    A structure used to model a TrueType font header table.  All       */
61   /*    fields follow the TrueType specification.                          */
62   /*                                                                       */
63   typedef struct  TT_Header_
64   {
65     FT_Fixed   Table_Version;
66     FT_Fixed   Font_Revision;
67 
68     FT_Long    CheckSum_Adjust;
69     FT_Long    Magic_Number;
70 
71     FT_UShort  Flags;
72     FT_UShort  Units_Per_EM;
73 
74     FT_Long    Created [2];
75     FT_Long    Modified[2];
76 
77     FT_Short   xMin;
78     FT_Short   yMin;
79     FT_Short   xMax;
80     FT_Short   yMax;
81 
82     FT_UShort  Mac_Style;
83     FT_UShort  Lowest_Rec_PPEM;
84 
85     FT_Short   Font_Direction;
86     FT_Short   Index_To_Loc_Format;
87     FT_Short   Glyph_Data_Format;
88 
89   } TT_Header;
90 
91 
92   /*************************************************************************/
93   /*                                                                       */
94   /* <Struct>                                                              */
95   /*    TT_HoriHeader                                                      */
96   /*                                                                       */
97   /* <Description>                                                         */
98   /*    A structure used to model a TrueType horizontal header, the `hhea' */
99   /*    table, as well as the corresponding horizontal metrics table,      */
100   /*    i.e., the `hmtx' table.                                            */
101   /*                                                                       */
102   /* <Fields>                                                              */
103   /*    Version                :: The table version.                       */
104   /*                                                                       */
105   /*    Ascender               :: The font's ascender, i.e., the distance  */
106   /*                              from the baseline to the top-most of all */
107   /*                              glyph points found in the font.          */
108   /*                                                                       */
109   /*                              This value is invalid in many fonts, as  */
110   /*                              it is usually set by the font designer,  */
111   /*                              and often reflects only a portion of the */
112   /*                              glyphs found in the font (maybe ASCII).  */
113   /*                                                                       */
114   /*                              You should use the `sTypoAscender' field */
115   /*                              of the OS/2 table instead if you want    */
116   /*                              the correct one.                         */
117   /*                                                                       */
118   /*    Descender              :: The font's descender, i.e., the distance */
119   /*                              from the baseline to the bottom-most of  */
120   /*                              all glyph points found in the font.  It  */
121   /*                              is negative.                             */
122   /*                                                                       */
123   /*                              This value is invalid in many fonts, as  */
124   /*                              it is usually set by the font designer,  */
125   /*                              and often reflects only a portion of the */
126   /*                              glyphs found in the font (maybe ASCII).  */
127   /*                                                                       */
128   /*                              You should use the `sTypoDescender'      */
129   /*                              field of the OS/2 table instead if you   */
130   /*                              want the correct one.                    */
131   /*                                                                       */
132   /*    Line_Gap               :: The font's line gap, i.e., the distance  */
133   /*                              to add to the ascender and descender to  */
134   /*                              get the BTB, i.e., the                   */
135   /*                              baseline-to-baseline distance for the    */
136   /*                              font.                                    */
137   /*                                                                       */
138   /*    advance_Width_Max      :: This field is the maximum of all advance */
139   /*                              widths found in the font.  It can be     */
140   /*                              used to compute the maximum width of an  */
141   /*                              arbitrary string of text.                */
142   /*                                                                       */
143   /*    min_Left_Side_Bearing  :: The minimum left side bearing of all     */
144   /*                              glyphs within the font.                  */
145   /*                                                                       */
146   /*    min_Right_Side_Bearing :: The minimum right side bearing of all    */
147   /*                              glyphs within the font.                  */
148   /*                                                                       */
149   /*    xMax_Extent            :: The maximum horizontal extent (i.e., the */
150   /*                              `width' of a glyph's bounding box) for   */
151   /*                              all glyphs in the font.                  */
152   /*                                                                       */
153   /*    caret_Slope_Rise       :: The rise coefficient of the cursor's     */
154   /*                              slope of the cursor (slope=rise/run).    */
155   /*                                                                       */
156   /*    caret_Slope_Run        :: The run coefficient of the cursor's      */
157   /*                              slope.                                   */
158   /*                                                                       */
159   /*    Reserved               :: 8~reserved bytes.                        */
160   /*                                                                       */
161   /*    metric_Data_Format     :: Always~0.                                */
162   /*                                                                       */
163   /*    number_Of_HMetrics     :: Number of HMetrics entries in the `hmtx' */
164   /*                              table -- this value can be smaller than  */
165   /*                              the total number of glyphs in the font.  */
166   /*                                                                       */
167   /*    long_metrics           :: A pointer into the `hmtx' table.         */
168   /*                                                                       */
169   /*    short_metrics          :: A pointer into the `hmtx' table.         */
170   /*                                                                       */
171   /* <Note>                                                                */
172   /*    IMPORTANT: The TT_HoriHeader and TT_VertHeader structures should   */
173   /*               be identical except for the names of their fields which */
174   /*               are different.                                          */
175   /*                                                                       */
176   /*               This ensures that a single function in the `ttload'     */
177   /*               module is able to read both the horizontal and vertical */
178   /*               headers.                                                */
179   /*                                                                       */
180   typedef struct  TT_HoriHeader_
181   {
182     FT_Fixed   Version;
183     FT_Short   Ascender;
184     FT_Short   Descender;
185     FT_Short   Line_Gap;
186 
187     FT_UShort  advance_Width_Max;      /* advance width maximum */
188 
189     FT_Short   min_Left_Side_Bearing;  /* minimum left-sb       */
190     FT_Short   min_Right_Side_Bearing; /* minimum right-sb      */
191     FT_Short   xMax_Extent;            /* xmax extents          */
192     FT_Short   caret_Slope_Rise;
193     FT_Short   caret_Slope_Run;
194     FT_Short   caret_Offset;
195 
196     FT_Short   Reserved[4];
197 
198     FT_Short   metric_Data_Format;
199     FT_UShort  number_Of_HMetrics;
200 
201     /* The following fields are not defined by the TrueType specification */
202     /* but they are used to connect the metrics header to the relevant    */
203     /* `HMTX' table.                                                      */
204 
205     void*      long_metrics;
206     void*      short_metrics;
207 
208   } TT_HoriHeader;
209 
210 
211   /*************************************************************************/
212   /*                                                                       */
213   /* <Struct>                                                              */
214   /*    TT_VertHeader                                                      */
215   /*                                                                       */
216   /* <Description>                                                         */
217   /*    A structure used to model a TrueType vertical header, the `vhea'   */
218   /*    table, as well as the corresponding vertical metrics table, i.e.,  */
219   /*    the `vmtx' table.                                                  */
220   /*                                                                       */
221   /* <Fields>                                                              */
222   /*    Version                 :: The table version.                      */
223   /*                                                                       */
224   /*    Ascender                :: The font's ascender, i.e., the distance */
225   /*                               from the baseline to the top-most of    */
226   /*                               all glyph points found in the font.     */
227   /*                                                                       */
228   /*                               This value is invalid in many fonts, as */
229   /*                               it is usually set by the font designer, */
230   /*                               and often reflects only a portion of    */
231   /*                               the glyphs found in the font (maybe     */
232   /*                               ASCII).                                 */
233   /*                                                                       */
234   /*                               You should use the `sTypoAscender'      */
235   /*                               field of the OS/2 table instead if you  */
236   /*                               want the correct one.                   */
237   /*                                                                       */
238   /*    Descender               :: The font's descender, i.e., the         */
239   /*                               distance from the baseline to the       */
240   /*                               bottom-most of all glyph points found   */
241   /*                               in the font.  It is negative.           */
242   /*                                                                       */
243   /*                               This value is invalid in many fonts, as */
244   /*                               it is usually set by the font designer, */
245   /*                               and often reflects only a portion of    */
246   /*                               the glyphs found in the font (maybe     */
247   /*                               ASCII).                                 */
248   /*                                                                       */
249   /*                               You should use the `sTypoDescender'     */
250   /*                               field of the OS/2 table instead if you  */
251   /*                               want the correct one.                   */
252   /*                                                                       */
253   /*    Line_Gap                :: The font's line gap, i.e., the distance */
254   /*                               to add to the ascender and descender to */
255   /*                               get the BTB, i.e., the                  */
256   /*                               baseline-to-baseline distance for the   */
257   /*                               font.                                   */
258   /*                                                                       */
259   /*    advance_Height_Max      :: This field is the maximum of all        */
260   /*                               advance heights found in the font.  It  */
261   /*                               can be used to compute the maximum      */
262   /*                               height of an arbitrary string of text.  */
263   /*                                                                       */
264   /*    min_Top_Side_Bearing    :: The minimum top side bearing of all     */
265   /*                               glyphs within the font.                 */
266   /*                                                                       */
267   /*    min_Bottom_Side_Bearing :: The minimum bottom side bearing of all  */
268   /*                               glyphs within the font.                 */
269   /*                                                                       */
270   /*    yMax_Extent             :: The maximum vertical extent (i.e., the  */
271   /*                               `height' of a glyph's bounding box) for */
272   /*                               all glyphs in the font.                 */
273   /*                                                                       */
274   /*    caret_Slope_Rise        :: The rise coefficient of the cursor's    */
275   /*                               slope of the cursor (slope=rise/run).   */
276   /*                                                                       */
277   /*    caret_Slope_Run         :: The run coefficient of the cursor's     */
278   /*                               slope.                                  */
279   /*                                                                       */
280   /*    caret_Offset            :: The cursor's offset for slanted fonts.  */
281   /*                               This value is `reserved' in vmtx        */
282   /*                               version 1.0.                            */
283   /*                                                                       */
284   /*    Reserved                :: 8~reserved bytes.                       */
285   /*                                                                       */
286   /*    metric_Data_Format      :: Always~0.                               */
287   /*                                                                       */
288   /*    number_Of_HMetrics      :: Number of VMetrics entries in the       */
289   /*                               `vmtx' table -- this value can be       */
290   /*                               smaller than the total number of glyphs */
291   /*                               in the font.                            */
292   /*                                                                       */
293   /*    long_metrics           :: A pointer into the `vmtx' table.         */
294   /*                                                                       */
295   /*    short_metrics          :: A pointer into the `vmtx' table.         */
296   /*                                                                       */
297   /* <Note>                                                                */
298   /*    IMPORTANT: The TT_HoriHeader and TT_VertHeader structures should   */
299   /*               be identical except for the names of their fields which */
300   /*               are different.                                          */
301   /*                                                                       */
302   /*               This ensures that a single function in the `ttload'     */
303   /*               module is able to read both the horizontal and vertical */
304   /*               headers.                                                */
305   /*                                                                       */
306   typedef struct  TT_VertHeader_
307   {
308     FT_Fixed   Version;
309     FT_Short   Ascender;
310     FT_Short   Descender;
311     FT_Short   Line_Gap;
312 
313     FT_UShort  advance_Height_Max;      /* advance height maximum */
314 
315     FT_Short   min_Top_Side_Bearing;    /* minimum left-sb or top-sb       */
316     FT_Short   min_Bottom_Side_Bearing; /* minimum right-sb or bottom-sb   */
317     FT_Short   yMax_Extent;             /* xmax or ymax extents            */
318     FT_Short   caret_Slope_Rise;
319     FT_Short   caret_Slope_Run;
320     FT_Short   caret_Offset;
321 
322     FT_Short   Reserved[4];
323 
324     FT_Short   metric_Data_Format;
325     FT_UShort  number_Of_VMetrics;
326 
327     /* The following fields are not defined by the TrueType specification */
328     /* but they're used to connect the metrics header to the relevant     */
329     /* `HMTX' or `VMTX' table.                                            */
330 
331     void*      long_metrics;
332     void*      short_metrics;
333 
334   } TT_VertHeader;
335 
336 
337   /*************************************************************************/
338   /*                                                                       */
339   /* <Struct>                                                              */
340   /*    TT_OS2                                                             */
341   /*                                                                       */
342   /* <Description>                                                         */
343   /*    A structure used to model a TrueType OS/2 table. This is the long  */
344   /*    table version.  All fields comply to the TrueType specification.   */
345   /*                                                                       */
346   /*    Note that we now support old Mac fonts which do not include an     */
347   /*    OS/2 table.  In this case, the `version' field is always set to    */
348   /*    0xFFFF.                                                            */
349   /*                                                                       */
350   typedef struct  TT_OS2_
351   {
352     FT_UShort  version;                /* 0x0001 - more or 0xFFFF */
353     FT_Short   xAvgCharWidth;
354     FT_UShort  usWeightClass;
355     FT_UShort  usWidthClass;
356     FT_Short   fsType;
357     FT_Short   ySubscriptXSize;
358     FT_Short   ySubscriptYSize;
359     FT_Short   ySubscriptXOffset;
360     FT_Short   ySubscriptYOffset;
361     FT_Short   ySuperscriptXSize;
362     FT_Short   ySuperscriptYSize;
363     FT_Short   ySuperscriptXOffset;
364     FT_Short   ySuperscriptYOffset;
365     FT_Short   yStrikeoutSize;
366     FT_Short   yStrikeoutPosition;
367     FT_Short   sFamilyClass;
368 
369     FT_Byte    panose[10];
370 
371     FT_ULong   ulUnicodeRange1;        /* Bits 0-31   */
372     FT_ULong   ulUnicodeRange2;        /* Bits 32-63  */
373     FT_ULong   ulUnicodeRange3;        /* Bits 64-95  */
374     FT_ULong   ulUnicodeRange4;        /* Bits 96-127 */
375 
376     FT_Char    achVendID[4];
377 
378     FT_UShort  fsSelection;
379     FT_UShort  usFirstCharIndex;
380     FT_UShort  usLastCharIndex;
381     FT_Short   sTypoAscender;
382     FT_Short   sTypoDescender;
383     FT_Short   sTypoLineGap;
384     FT_UShort  usWinAscent;
385     FT_UShort  usWinDescent;
386 
387     /* only version 1 tables: */
388 
389     FT_ULong   ulCodePageRange1;       /* Bits 0-31   */
390     FT_ULong   ulCodePageRange2;       /* Bits 32-63  */
391 
392     /* only version 2 tables: */
393 
394     FT_Short   sxHeight;
395     FT_Short   sCapHeight;
396     FT_UShort  usDefaultChar;
397     FT_UShort  usBreakChar;
398     FT_UShort  usMaxContext;
399 
400   } TT_OS2;
401 
402 
403   /*************************************************************************/
404   /*                                                                       */
405   /* <Struct>                                                              */
406   /*    TT_Postscript                                                      */
407   /*                                                                       */
408   /* <Description>                                                         */
409   /*    A structure used to model a TrueType PostScript table.  All fields */
410   /*    comply to the TrueType specification.  This structure does not     */
411   /*    reference the PostScript glyph names, which can be nevertheless    */
412   /*    accessed with the `ttpost' module.                                 */
413   /*                                                                       */
414   typedef struct  TT_Postscript_
415   {
416     FT_Fixed  FormatType;
417     FT_Fixed  italicAngle;
418     FT_Short  underlinePosition;
419     FT_Short  underlineThickness;
420     FT_ULong  isFixedPitch;
421     FT_ULong  minMemType42;
422     FT_ULong  maxMemType42;
423     FT_ULong  minMemType1;
424     FT_ULong  maxMemType1;
425 
426     /* Glyph names follow in the file, but we don't   */
427     /* load them by default.  See the ttpost.c file.  */
428 
429   } TT_Postscript;
430 
431 
432   /*************************************************************************/
433   /*                                                                       */
434   /* <Struct>                                                              */
435   /*    TT_PCLT                                                            */
436   /*                                                                       */
437   /* <Description>                                                         */
438   /*    A structure used to model a TrueType PCLT table.  All fields       */
439   /*    comply to the TrueType specification.                              */
440   /*                                                                       */
441   typedef struct  TT_PCLT_
442   {
443     FT_Fixed   Version;
444     FT_ULong   FontNumber;
445     FT_UShort  Pitch;
446     FT_UShort  xHeight;
447     FT_UShort  Style;
448     FT_UShort  TypeFamily;
449     FT_UShort  CapHeight;
450     FT_UShort  SymbolSet;
451     FT_Char    TypeFace[16];
452     FT_Char    CharacterComplement[8];
453     FT_Char    FileName[6];
454     FT_Char    StrokeWeight;
455     FT_Char    WidthType;
456     FT_Byte    SerifStyle;
457     FT_Byte    Reserved;
458 
459   } TT_PCLT;
460 
461 
462   /*************************************************************************/
463   /*                                                                       */
464   /* <Struct>                                                              */
465   /*    TT_MaxProfile                                                      */
466   /*                                                                       */
467   /* <Description>                                                         */
468   /*    The maximum profile is a table containing many max values which    */
469   /*    can be used to pre-allocate arrays.  This ensures that no memory   */
470   /*    allocation occurs during a glyph load.                             */
471   /*                                                                       */
472   /* <Fields>                                                              */
473   /*    version               :: The version number.                       */
474   /*                                                                       */
475   /*    numGlyphs             :: The number of glyphs in this TrueType     */
476   /*                             font.                                     */
477   /*                                                                       */
478   /*    maxPoints             :: The maximum number of points in a         */
479   /*                             non-composite TrueType glyph.  See also   */
480   /*                             the structure element                     */
481   /*                             `maxCompositePoints'.                     */
482   /*                                                                       */
483   /*    maxContours           :: The maximum number of contours in a       */
484   /*                             non-composite TrueType glyph.  See also   */
485   /*                             the structure element                     */
486   /*                             `maxCompositeContours'.                   */
487   /*                                                                       */
488   /*    maxCompositePoints    :: The maximum number of points in a         */
489   /*                             composite TrueType glyph.  See also the   */
490   /*                             structure element `maxPoints'.            */
491   /*                                                                       */
492   /*    maxCompositeContours  :: The maximum number of contours in a       */
493   /*                             composite TrueType glyph.  See also the   */
494   /*                             structure element `maxContours'.          */
495   /*                                                                       */
496   /*    maxZones              :: The maximum number of zones used for      */
497   /*                             glyph hinting.                            */
498   /*                                                                       */
499   /*    maxTwilightPoints     :: The maximum number of points in the       */
500   /*                             twilight zone used for glyph hinting.     */
501   /*                                                                       */
502   /*    maxStorage            :: The maximum number of elements in the     */
503   /*                             storage area used for glyph hinting.      */
504   /*                                                                       */
505   /*    maxFunctionDefs       :: The maximum number of function            */
506   /*                             definitions in the TrueType bytecode for  */
507   /*                             this font.                                */
508   /*                                                                       */
509   /*    maxInstructionDefs    :: The maximum number of instruction         */
510   /*                             definitions in the TrueType bytecode for  */
511   /*                             this font.                                */
512   /*                                                                       */
513   /*    maxStackElements      :: The maximum number of stack elements used */
514   /*                             during bytecode interpretation.           */
515   /*                                                                       */
516   /*    maxSizeOfInstructions :: The maximum number of TrueType opcodes    */
517   /*                             used for glyph hinting.                   */
518   /*                                                                       */
519   /*    maxComponentElements  :: The maximum number of simple (i.e., non-  */
520   /*                             composite) glyphs in a composite glyph.   */
521   /*                                                                       */
522   /*    maxComponentDepth     :: The maximum nesting depth of composite    */
523   /*                             glyphs.                                   */
524   /*                                                                       */
525   /* <Note>                                                                */
526   /*    This structure is only used during font loading.                   */
527   /*                                                                       */
528   typedef struct  TT_MaxProfile_
529   {
530     FT_Fixed   version;
531     FT_UShort  numGlyphs;
532     FT_UShort  maxPoints;
533     FT_UShort  maxContours;
534     FT_UShort  maxCompositePoints;
535     FT_UShort  maxCompositeContours;
536     FT_UShort  maxZones;
537     FT_UShort  maxTwilightPoints;
538     FT_UShort  maxStorage;
539     FT_UShort  maxFunctionDefs;
540     FT_UShort  maxInstructionDefs;
541     FT_UShort  maxStackElements;
542     FT_UShort  maxSizeOfInstructions;
543     FT_UShort  maxComponentElements;
544     FT_UShort  maxComponentDepth;
545 
546   } TT_MaxProfile;
547 
548 
549   /*************************************************************************/
550   /*                                                                       */
551   /* <Enum>                                                                */
552   /*    FT_Sfnt_Tag                                                        */
553   /*                                                                       */
554   /* <Description>                                                         */
555   /*    An enumeration used to specify the index of an SFNT table.         */
556   /*    Used in the @FT_Get_Sfnt_Table API function.                       */
557   /*                                                                       */
558   typedef enum  FT_Sfnt_Tag_
559   {
560     ft_sfnt_head = 0,
561     ft_sfnt_maxp = 1,
562     ft_sfnt_os2  = 2,
563     ft_sfnt_hhea = 3,
564     ft_sfnt_vhea = 4,
565     ft_sfnt_post = 5,
566     ft_sfnt_pclt = 6,
567 
568     sfnt_max   /* internal end mark */
569 
570   } FT_Sfnt_Tag;
571 
572   /* */
573 
574 
575   /*************************************************************************/
576   /*                                                                       */
577   /* <Function>                                                            */
578   /*    FT_Get_Sfnt_Table                                                  */
579   /*                                                                       */
580   /* <Description>                                                         */
581   /*    Return a pointer to a given SFNT table within a face.              */
582   /*                                                                       */
583   /* <Input>                                                               */
584   /*    face :: A handle to the source.                                    */
585   /*                                                                       */
586   /*    tag  :: The index of the SFNT table.                               */
587   /*                                                                       */
588   /* <Return>                                                              */
589   /*    A type-less pointer to the table.  This will be~0 in case of       */
590   /*    error, or if the corresponding table was not found *OR* loaded     */
591   /*    from the file.                                                     */
592   /*                                                                       */
593   /* <Note>                                                                */
594   /*    The table is owned by the face object and disappears with it.      */
595   /*                                                                       */
596   /*    This function is only useful to access SFNT tables that are loaded */
597   /*    by the sfnt, truetype, and opentype drivers.  See @FT_Sfnt_Tag for */
598   /*    a list.                                                            */
599   /*                                                                       */
600   FT_EXPORT( void* )
601   FT_Get_Sfnt_Table( FT_Face      face,
602                      FT_Sfnt_Tag  tag );
603 
604 
605  /**************************************************************************
606   *
607   * @function:
608   *   FT_Load_Sfnt_Table
609   *
610   * @description:
611   *   Load any font table into client memory.
612   *
613   * @input:
614   *   face ::
615   *     A handle to the source face.
616   *
617   *   tag ::
618   *     The four-byte tag of the table to load.  Use the value~0 if you want
619   *     to access the whole font file.  Otherwise, you can use one of the
620   *     definitions found in the @FT_TRUETYPE_TAGS_H file, or forge a new
621   *     one with @FT_MAKE_TAG.
622   *
623   *   offset ::
624   *     The starting offset in the table (or file if tag == 0).
625   *
626   * @output:
627   *   buffer ::
628   *     The target buffer address.  The client must ensure that the memory
629   *     array is big enough to hold the data.
630   *
631   * @inout:
632   *   length ::
633   *     If the `length' parameter is NULL, then try to load the whole table.
634   *     Return an error code if it fails.
635   *
636   *     Else, if `*length' is~0, exit immediately while returning the
637   *     table's (or file) full size in it.
638   *
639   *     Else the number of bytes to read from the table or file, from the
640   *     starting offset.
641   *
642   * @return:
643   *   FreeType error code.  0~means success.
644   *
645   * @note:
646   *   If you need to determine the table's length you should first call this
647   *   function with `*length' set to~0, as in the following example:
648   *
649   *     {
650   *       FT_ULong  length = 0;
651   *
652   *
653   *       error = FT_Load_Sfnt_Table( face, tag, 0, NULL, &length );
654   *       if ( error ) { ... table does not exist ... }
655   *
656   *       buffer = malloc( length );
657   *       if ( buffer == NULL ) { ... not enough memory ... }
658   *
659   *       error = FT_Load_Sfnt_Table( face, tag, 0, buffer, &length );
660   *       if ( error ) { ... could not load table ... }
661   *     }
662   */
663   FT_EXPORT( FT_Error )
664   FT_Load_Sfnt_Table( FT_Face    face,
665                       FT_ULong   tag,
666                       FT_Long    offset,
667                       FT_Byte*   buffer,
668                       FT_ULong*  length );
669 
670 
671  /**************************************************************************
672   *
673   * @function:
674   *   FT_Sfnt_Table_Info
675   *
676   * @description:
677   *   Return information on an SFNT table.
678   *
679   * @input:
680   *   face ::
681   *     A handle to the source face.
682   *
683   *   table_index ::
684   *     The index of an SFNT table.  The function returns
685   *     FT_Err_Table_Missing for an invalid value.
686   *
687   * @output:
688   *   tag ::
689   *     The name tag of the SFNT table.
690   *
691   *   length ::
692   *     The length of the SFNT table.
693   *
694   * @return:
695   *   FreeType error code.  0~means success.
696   *
697   * @note:
698   *   SFNT tables with length zero are treated as missing.
699   *
700   */
701   FT_EXPORT( FT_Error )
702   FT_Sfnt_Table_Info( FT_Face    face,
703                       FT_UInt    table_index,
704                       FT_ULong  *tag,
705                       FT_ULong  *length );
706 
707 
708   /*************************************************************************/
709   /*                                                                       */
710   /* <Function>                                                            */
711   /*    FT_Get_CMap_Language_ID                                            */
712   /*                                                                       */
713   /* <Description>                                                         */
714   /*    Return TrueType/sfnt specific cmap language ID.  Definitions of    */
715   /*    language ID values are in `freetype/ttnameid.h'.                   */
716   /*                                                                       */
717   /* <Input>                                                               */
718   /*    charmap ::                                                         */
719   /*      The target charmap.                                              */
720   /*                                                                       */
721   /* <Return>                                                              */
722   /*    The language ID of `charmap'.  If `charmap' doesn't belong to a    */
723   /*    TrueType/sfnt face, just return~0 as the default value.            */
724   /*                                                                       */
725   FT_EXPORT( FT_ULong )
726   FT_Get_CMap_Language_ID( FT_CharMap  charmap );
727 
728 
729   /*************************************************************************/
730   /*                                                                       */
731   /* <Function>                                                            */
732   /*    FT_Get_CMap_Format                                                 */
733   /*                                                                       */
734   /* <Description>                                                         */
735   /*    Return TrueType/sfnt specific cmap format.                         */
736   /*                                                                       */
737   /* <Input>                                                               */
738   /*    charmap ::                                                         */
739   /*      The target charmap.                                              */
740   /*                                                                       */
741   /* <Return>                                                              */
742   /*    The format of `charmap'.  If `charmap' doesn't belong to a         */
743   /*    TrueType/sfnt face, return -1.                                     */
744   /*                                                                       */
745   FT_EXPORT( FT_Long )
746   FT_Get_CMap_Format( FT_CharMap  charmap );
747 
748   /* */
749 
750 
751 FT_END_HEADER
752 
753 #endif /* __TTTABLES_H__ */
754 
755 
756 /* END */
757