ttobjs.h 18.2 KB
Newer Older
David Turner's avatar
David Turner committed
1
2
3
4
5
6
/***************************************************************************/
/*                                                                         */
/*  ttobjs.h                                                               */
/*                                                                         */
/*    Objects manager (specification).                                     */
/*                                                                         */
Werner Lemberg's avatar
   
Werner Lemberg committed
7
/*  Copyright 1996-2000 by                                                 */
David Turner's avatar
David Turner committed
8
9
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
Werner Lemberg's avatar
   
Werner Lemberg committed
10
11
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
David Turner's avatar
David Turner committed
12
13
14
15
16
17
18
19
20
21
22
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/


#ifndef TTOBJS_H
#define TTOBJS_H


23
24
#include <freetype/internal/ftobjs.h>
#include <freetype/internal/tttypes.h>
Werner Lemberg's avatar
   
Werner Lemberg committed
25
#include <freetype/internal/tterrors.h>
David Turner's avatar
David Turner committed
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79


#ifdef __cplusplus
  extern "C" {
#endif


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    TT_Driver                                                          */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a TrueType driver object.                              */
  /*                                                                       */
  typedef struct TT_DriverRec_*  TT_Driver;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    TT_Instance                                                        */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a TrueType size object.                                */
  /*                                                                       */
  typedef struct TT_SizeRec_*  TT_Size;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    TT_GlyphSlot                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a TrueType glyph slot object.                          */
  /*                                                                       */
  /* <Note>                                                                */
  /*    This is a direct typedef of FT_GlyphSlot, as there is nothing      */
  /*    specific about the TrueType glyph slot.                            */
  /*                                                                       */
  typedef FT_GlyphSlot  TT_GlyphSlot;


  /*************************************************************************/
  /*                                                                       */
  /* <Struct>                                                              */
  /*    TT_GraphicsState                                                   */
  /*                                                                       */
  /* <Description>                                                         */
  /*    The TrueType graphics state used during bytecode interpretation.   */
  /*                                                                       */
  typedef struct  TT_GraphicsState_
  {
80
81
82
    FT_UShort      rp0;
    FT_UShort      rp1;
    FT_UShort      rp2;
David Turner's avatar
David Turner committed
83

84
85
86
    FT_UnitVector  dualVector;
    FT_UnitVector  projVector;
    FT_UnitVector  freeVector;
David Turner's avatar
David Turner committed
87

88
89
90
    FT_Long        loop;
    FT_F26Dot6     minimum_distance;
    FT_Int         round_state;
David Turner's avatar
David Turner committed
91

92
93
94
95
96
97
    FT_Bool        auto_flip;
    FT_F26Dot6     control_value_cutin;
    FT_F26Dot6     single_width_cutin;
    FT_F26Dot6     single_width_value;
    FT_Short       delta_base;
    FT_Short       delta_shift;
David Turner's avatar
David Turner committed
98

99
100
101
    FT_Byte        instruct_control;
    FT_Bool        scan_control;
    FT_Int         scan_type;
David Turner's avatar
David Turner committed
102

103
104
105
    FT_UShort      gep0;
    FT_UShort      gep1;
    FT_UShort      gep2;
David Turner's avatar
David Turner committed
106
107
108

  } TT_GraphicsState;

Werner Lemberg's avatar
   
Werner Lemberg committed
109

Werner Lemberg's avatar
   
Werner Lemberg committed
110
111
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER

112
  FT_LOCAL void  TT_Done_GlyphZone( TT_GlyphZone*  zone );
113

114
  FT_LOCAL FT_Error TT_New_GlyphZone( FT_Memory      memory,
115
116
117
118
                                       FT_UShort      maxPoints,
                                       FT_Short       maxContours,
                                       TT_GlyphZone*  zone );

Werner Lemberg's avatar
   
Werner Lemberg committed
119
120
#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */

Werner Lemberg's avatar
   
Werner Lemberg committed
121

122

David Turner's avatar
David Turner committed
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
  /*************************************************************************/
  /*                                                                       */
  /*  EXECUTION SUBTABLES                                                  */
  /*                                                                       */
  /*  These sub-tables relate to instruction execution.                    */
  /*                                                                       */
  /*************************************************************************/


#define TT_MAX_CODE_RANGES  3


  /*************************************************************************/
  /*                                                                       */
  /* There can only be 3 active code ranges at once:                       */
  /*   - the Font Program                                                  */
  /*   - the CVT Program                                                   */
  /*   - a glyph's instructions set                                        */
  /*                                                                       */
  typedef enum  TT_CodeRange_Tag_
  {
    tt_coderange_none = 0,
    tt_coderange_font,
    tt_coderange_cvt,
    tt_coderange_glyph

  } TT_CodeRange_Tag;


  typedef struct  TT_CodeRange_
  {
154
155
    FT_Byte*  base;
    FT_ULong  size;
David Turner's avatar
David Turner committed
156
157
158
159
160
161
162
163
164
165
166
167

  } TT_CodeRange;

  typedef TT_CodeRange  TT_CodeRangeTable[TT_MAX_CODE_RANGES];


  /*************************************************************************/
  /*                                                                       */
  /* Defines a function/instruction definition record.                     */
  /*                                                                       */
  typedef struct  TT_DefRecord_
  {
168
169
170
171
    FT_Int   range;      /* in which code range is it located? */
    FT_Long  start;      /* where does it start?               */
    FT_UInt  opc;        /* function #, or instruction code    */
    FT_Bool  active;     /* is it active?                      */
David Turner's avatar
David Turner committed
172
173
174
175
176
177
178
179
180
181

  } TT_DefRecord, *TT_DefArray;


  /*************************************************************************/
  /*                                                                       */
  /* Subglyph transformation record.                                       */
  /*                                                                       */
  typedef struct  TT_Transform_
  {
182
183
184
    FT_Fixed    xx, xy;     /* transformation matrix coefficients */
    FT_Fixed    yx, yy;
    FT_F26Dot6  ox, oy;     /* offsets        */
David Turner's avatar
David Turner committed
185
186
187
188
189
190
191
192
193
194

  } TT_Transform;


  /*************************************************************************/
  /*                                                                       */
  /* Subglyph loading record.  Used to load composite components.          */
  /*                                                                       */
  typedef struct  TT_SubglyphRec_
  {
195
196
197
198
    FT_Long       index;        /* subglyph index; initialized with -1 */
    FT_Bool       is_scaled;    /* is the subglyph scaled?             */
    FT_Bool       is_hinted;    /* should it be hinted?                */
    FT_Bool       preserve_pps; /* preserve phantom points?            */
David Turner's avatar
David Turner committed
199

200
    FT_Long       file_offset;
David Turner's avatar
David Turner committed
201

202
203
204
    FT_BBox       bbox;
    FT_Pos        left_bearing;
    FT_Pos        advance;
David Turner's avatar
David Turner committed
205

206
    TT_GlyphZone  zone;
David Turner's avatar
David Turner committed
207

208
209
    FT_Long       arg1;         /* first argument                      */
    FT_Long       arg2;         /* second argument                     */
David Turner's avatar
David Turner committed
210

211
    FT_UShort     element_flag; /* current load element flag           */
David Turner's avatar
David Turner committed
212
213
214

    TT_Transform  transform;    /* transformation matrix               */

215
    FT_Vector     pp1, pp2;     /* phantom points                      */
David Turner's avatar
David Turner committed
216
217
218
219
220
221
222
223

  } TT_SubGlyphRec, *TT_SubGlyph_Stack;


  /*************************************************************************/
  /*                                                                       */
  /* A note regarding non-squared pixels:                                  */
  /*                                                                       */
Werner Lemberg's avatar
   
Werner Lemberg committed
224
  /* (This text will probably go into some docs at some time; for now, it  */
David Turner's avatar
David Turner committed
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
  /*  is kept here to explain some definitions in the TIns_Metrics         */
  /*  record).                                                             */
  /*                                                                       */
  /* The CVT is a one-dimensional array containing values that control     */
  /* certain important characteristics in a font, like the height of all   */
  /* capitals, all lowercase letter, default spacing or stem width/height. */
  /*                                                                       */
  /* These values are found in FUnits in the font file, and must be scaled */
  /* to pixel coordinates before being used by the CVT and glyph programs. */
  /* Unfortunately, when using distinct x and y resolutions (or distinct x */
  /* and y pointsizes), there are two possible scalings.                   */
  /*                                                                       */
  /* A first try was to implement a `lazy' scheme where all values were    */
  /* scaled when first used.  However, while some values are always used   */
  /* in the same direction, some others are used under many different      */
  /* circumstances and orientations.                                       */
  /*                                                                       */
  /* I have found a simpler way to do the same, and it even seems to work  */
  /* in most of the cases:                                                 */
  /*                                                                       */
  /* - All CVT values are scaled to the maximum ppem size.                 */
  /*                                                                       */
  /* - When performing a read or write in the CVT, a ratio factor is used  */
  /*   to perform adequate scaling.  Example:                              */
  /*                                                                       */
  /*     x_ppem = 14                                                       */
  /*     y_ppem = 10                                                       */
  /*                                                                       */
  /*   We choose ppem = x_ppem = 14 as the CVT scaling size.  All cvt      */
  /*   entries are scaled to it.                                           */
  /*                                                                       */
  /*     x_ratio = 1.0                                                     */
  /*     y_ratio = y_ppem/ppem (< 1.0)                                     */
  /*                                                                       */
  /*   We compute the current ratio like:                                  */
  /*                                                                       */
  /*   - If projVector is horizontal,                                      */
  /*       ratio = x_ratio = 1.0                                           */
  /*                                                                       */
  /*   - if projVector is vertical,                                        */
  /*       ratio = y_ratio                                                 */
  /*                                                                       */
  /*   - else,                                                             */
  /*       ratio = sqrt( (proj.x * x_ratio) ^ 2 + (proj.y * y_ratio) ^ 2 ) */
  /*                                                                       */
  /*   Reading a cvt value returns                                         */
  /*     ratio * cvt[index]                                                */
  /*                                                                       */
  /*   Writing a cvt value in pixels:                                      */
  /*     cvt[index] / ratio                                                */
  /*                                                                       */
  /*   The current ppem is simply                                          */
  /*     ratio * ppem                                                      */
  /*                                                                       */
  /*************************************************************************/


  /*************************************************************************/
  /*                                                                       */
  /* Metrics used by the TrueType size and context objects.                */
  /*                                                                       */
  typedef struct  TT_Size_Metrics_
  {
    /* for non-square pixels */
289
290
    FT_Long     x_ratio;
    FT_Long     y_ratio;
David Turner's avatar
David Turner committed
291

292
293
294
    FT_UShort   ppem;               /* maximum ppem size              */
    FT_Long     ratio;              /* current ratio                  */
    FT_Fixed    scale;
David Turner's avatar
David Turner committed
295

296
    FT_F26Dot6  compensations[4];   /* device-specific compensations  */
David Turner's avatar
David Turner committed
297

298
    FT_Bool     valid;
David Turner's avatar
David Turner committed
299

300
301
    FT_Bool     rotated;            /* `is the glyph rotated?'-flag   */
    FT_Bool     stretched;          /* `is the glyph stretched?'-flag */
David Turner's avatar
David Turner committed
302
303
304
305

  } TT_Size_Metrics;


Werner Lemberg's avatar
   
Werner Lemberg committed
306
307
308
309
  /*************************************************************************/
  /*                                                                       */
  /* TrueType size class.                                                  */
  /*                                                                       */
David Turner's avatar
David Turner committed
310
311
312
313
314
315
  typedef struct  TT_SizeRec_
  {
    FT_SizeRec         root;

    TT_Size_Metrics    ttmetrics;

316
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
Werner Lemberg's avatar
   
Werner Lemberg committed
317

318
319
    FT_UInt            num_function_defs; /* number of function definitions */
    FT_UInt            max_function_defs;
David Turner's avatar
David Turner committed
320
321
    TT_DefArray        function_defs;     /* table of function definitions  */

322
323
    FT_UInt            num_instruction_defs;  /* number of ins. definitions */
    FT_UInt            max_instruction_defs;
David Turner's avatar
David Turner committed
324
325
    TT_DefArray        instruction_defs;      /* table of ins. definitions  */

326
327
    FT_UInt            max_func;
    FT_UInt            max_ins;
David Turner's avatar
David Turner committed
328
329
330
331
332

    TT_CodeRangeTable  codeRangeTable;

    TT_GraphicsState   GS;

333
334
    FT_ULong           cvt_size;      /* the scaled control value table */
    FT_Long*           cvt;
David Turner's avatar
David Turner committed
335

336
337
    FT_UShort          storage_size; /* The storage area is now part of */
    FT_Long*           storage;      /* the instance                    */
David Turner's avatar
David Turner committed
338

339
    TT_GlyphZone       twilight;     /* The instance's twilight zone    */
David Turner's avatar
David Turner committed
340
341
342
343
344
345
346

    /* debugging variables */

    /* When using the debugger, we must keep the */
    /* execution context tied to the instance    */
    /* object rather than asking it on demand.   */

347
    FT_Bool            debug;
David Turner's avatar
David Turner committed
348
349
    TT_ExecContext     context;

350
351
#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */

David Turner's avatar
David Turner committed
352
353
354
  } TT_SizeRec;


Werner Lemberg's avatar
   
Werner Lemberg committed
355
356
357
358
  /*************************************************************************/
  /*                                                                       */
  /* TrueType driver class.                                                */
  /*                                                                       */
David Turner's avatar
David Turner committed
359
360
361
  typedef struct  TT_DriverRec_
  {
    FT_DriverRec    root;
362
    TT_ExecContext  context;  /* execution context        */
363
    TT_GlyphZone    zone;     /* glyph loader points zone */
David Turner's avatar
David Turner committed
364
365
366
367
368
369

    void*           extension_component;

  } TT_DriverRec;


Werner Lemberg's avatar
   
Werner Lemberg committed
370
371
372
373
  /*************************************************************************/
  /*                                                                       */
  /* Face functions                                                        */
  /*                                                                       */
374
  FT_LOCAL
375
  FT_Error  TT_Init_Face( FT_Stream      stream,
Werner Lemberg's avatar
   
Werner Lemberg committed
376
                          TT_Face        face,
377
378
                          FT_Int         face_index,
                          FT_Int         num_params,
Werner Lemberg's avatar
   
Werner Lemberg committed
379
                          FT_Parameter*  params );
David Turner's avatar
David Turner committed
380

381
  FT_LOCAL
Werner Lemberg's avatar
   
Werner Lemberg committed
382
  void  TT_Done_Face( TT_Face  face );
David Turner's avatar
David Turner committed
383
384


Werner Lemberg's avatar
   
Werner Lemberg committed
385
386
387
388
  /*************************************************************************/
  /*                                                                       */
  /* Size functions                                                        */
  /*                                                                       */
389
  FT_LOCAL
390
  FT_Error  TT_Init_Size( TT_Size  size );
David Turner's avatar
David Turner committed
391

392
  FT_LOCAL
Werner Lemberg's avatar
   
Werner Lemberg committed
393
  void  TT_Done_Size( TT_Size  size );
David Turner's avatar
David Turner committed
394

395
  FT_LOCAL
396
  FT_Error  TT_Reset_Size( TT_Size  size );
David Turner's avatar
David Turner committed
397
398


Werner Lemberg's avatar
   
Werner Lemberg committed
399
400
401
402
  /*************************************************************************/
  /*                                                                       */
  /* Driver functions                                                      */
  /*                                                                       */
403
  FT_LOCAL
404
  FT_Error  TT_Init_Driver( TT_Driver  driver );
David Turner's avatar
David Turner committed
405

406
  FT_LOCAL
Werner Lemberg's avatar
   
Werner Lemberg committed
407
  void  TT_Done_Driver( TT_Driver  driver );
David Turner's avatar
David Turner committed
408

Werner Lemberg's avatar
   
Werner Lemberg committed
409

David Turner's avatar
David Turner committed
410
411
412
413
414
415
416
417
#ifdef __cplusplus
  }
#endif

#endif /* TTOBJS_H */


/* END */