1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
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
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
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
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
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
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
|
/***************************************************************************/
/* */
/* ttobjs.h */
/* */
/* Objects manager (specification). */
/* */
/* Copyright 1996-2009, 2011-2014 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/* modified, and distributed under the terms of the FreeType project */
/* 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__
#include <ft2build.h>
#include <internal/ftobjs.h>
#include <internal/tttypes.h>
FT_BEGIN_HEADER
/*************************************************************************/
/* */
/* <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_
{
FT_UShort rp0;
FT_UShort rp1;
FT_UShort rp2;
FT_UnitVector dualVector;
FT_UnitVector projVector;
FT_UnitVector freeVector;
#ifdef TT_CONFIG_OPTION_UNPATENTED_HINTING
FT_Bool both_x_axis;
#endif
FT_Long loop;
FT_F26Dot6 minimum_distance;
FT_Int round_state;
FT_Bool auto_flip;
FT_F26Dot6 control_value_cutin;
FT_F26Dot6 single_width_cutin;
FT_F26Dot6 single_width_value;
FT_UShort delta_base;
FT_UShort delta_shift;
FT_Byte instruct_control;
/* According to Greg Hitchcock from Microsoft, the `scan_control' */
/* variable as documented in the TrueType specification is a 32-bit */
/* integer; the high-word part holds the SCANTYPE value, the low-word */
/* part the SCANCTRL value. We separate it into two fields. */
FT_Bool scan_control;
FT_Int scan_type;
FT_UShort gep0;
FT_UShort gep1;
FT_UShort gep2;
} TT_GraphicsState;
#ifdef TT_USE_BYTECODE_INTERPRETER
FT_LOCAL( void )
tt_glyphzone_done( TT_GlyphZone zone );
FT_LOCAL( FT_Error )
tt_glyphzone_new( FT_Memory memory,
FT_UShort maxPoints,
FT_Short maxContours,
TT_GlyphZone zone );
#endif /* TT_USE_BYTECODE_INTERPRETER */
/*************************************************************************/
/* */
/* 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_
{
FT_Byte* base;
FT_ULong size;
} TT_CodeRange;
typedef TT_CodeRange TT_CodeRangeTable[TT_MAX_CODE_RANGES];
/*************************************************************************/
/* */
/* Defines a function/instruction definition record. */
/* */
typedef struct TT_DefRecord_
{
FT_Int range; /* in which code range is it located? */
FT_Long start; /* where does it start? */
FT_Long end; /* where does it end? */
FT_UInt opc; /* function #, or instruction code */
FT_Bool active; /* is it active? */
FT_Bool inline_delta; /* is function that defines inline delta? */
FT_ULong sph_fdef_flags; /* flags to identify special functions */
} TT_DefRecord, *TT_DefArray;
/*************************************************************************/
/* */
/* Subglyph transformation record. */
/* */
typedef struct TT_Transform_
{
FT_Fixed xx, xy; /* transformation matrix coefficients */
FT_Fixed yx, yy;
FT_F26Dot6 ox, oy; /* offsets */
} TT_Transform;
/*************************************************************************/
/* */
/* A note regarding non-squared pixels: */
/* */
/* (This text will probably go into some docs at some time; for now, it */
/* is kept here to explain some definitions in the TT_Size_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 */
FT_Long x_ratio;
FT_Long y_ratio;
FT_UShort ppem; /* maximum ppem size */
FT_Long ratio; /* current ratio */
FT_Fixed scale;
FT_F26Dot6 compensations[4]; /* device-specific compensations */
FT_Bool valid;
FT_Bool rotated; /* `is the glyph rotated?'-flag */
FT_Bool stretched; /* `is the glyph stretched?'-flag */
} TT_Size_Metrics;
/*************************************************************************/
/* */
/* TrueType size class. */
/* */
typedef struct TT_SizeRec_
{
FT_SizeRec root;
/* we have our own copy of metrics so that we can modify */
/* it without affecting auto-hinting (when used) */
FT_Size_Metrics metrics;
TT_Size_Metrics ttmetrics;
FT_ULong strike_index; /* 0xFFFFFFFF to indicate invalid */
#ifdef TT_USE_BYTECODE_INTERPRETER
FT_UInt num_function_defs; /* number of function definitions */
FT_UInt max_function_defs;
TT_DefArray function_defs; /* table of function definitions */
FT_UInt num_instruction_defs; /* number of ins. definitions */
FT_UInt max_instruction_defs;
TT_DefArray instruction_defs; /* table of ins. definitions */
FT_UInt max_func;
FT_UInt max_ins;
TT_CodeRangeTable codeRangeTable;
TT_GraphicsState GS;
FT_ULong cvt_size; /* the scaled control value table */
FT_Long* cvt;
FT_UShort storage_size; /* The storage area is now part of */
FT_Long* storage; /* the instance */
TT_GlyphZoneRec twilight; /* The instance's twilight zone */
/* debugging variables */
/* When using the debugger, we must keep the */
/* execution context tied to the instance */
/* object rather than asking it on demand. */
FT_Bool debug;
TT_ExecContext context;
/* if negative, `fpgm' (resp. `prep'), wasn't executed yet; */
/* otherwise it is the returned error code */
FT_Error bytecode_ready;
FT_Error cvt_ready;
#endif /* TT_USE_BYTECODE_INTERPRETER */
} TT_SizeRec;
/*************************************************************************/
/* */
/* TrueType driver class. */
/* */
typedef struct TT_DriverRec_
{
FT_DriverRec root;
TT_ExecContext context; /* execution context */
TT_GlyphZoneRec zone; /* glyph loader points zone */
FT_UInt interpreter_version;
} TT_DriverRec;
/* Note: All of the functions below (except tt_size_reset()) are used */
/* as function pointers in a FT_Driver_ClassRec. Therefore their */
/* parameters are of types FT_Face, FT_Size, etc., rather than TT_Face, */
/* TT_Size, etc., so that the compiler can confirm that the types and */
/* number of parameters are correct. In all cases the FT_xxx types are */
/* cast to their TT_xxx counterparts inside the functions since FreeType */
/* will always use the TT driver to create them. */
/*************************************************************************/
/* */
/* Face functions */
/* */
FT_LOCAL( FT_Error )
tt_face_init( FT_Stream stream,
FT_Face ttface, /* TT_Face */
FT_Int face_index,
FT_Int num_params,
FT_Parameter* params );
FT_LOCAL( void )
tt_face_done( FT_Face ttface ); /* TT_Face */
/*************************************************************************/
/* */
/* Size functions */
/* */
FT_LOCAL( FT_Error )
tt_size_init( FT_Size ttsize ); /* TT_Size */
FT_LOCAL( void )
tt_size_done( FT_Size ttsize ); /* TT_Size */
#ifdef TT_USE_BYTECODE_INTERPRETER
FT_LOCAL( FT_Error )
tt_size_run_fpgm( TT_Size size,
FT_Bool pedantic );
FT_LOCAL( FT_Error )
tt_size_run_prep( TT_Size size,
FT_Bool pedantic );
FT_LOCAL( FT_Error )
tt_size_ready_bytecode( TT_Size size,
FT_Bool pedantic );
#endif /* TT_USE_BYTECODE_INTERPRETER */
FT_LOCAL( FT_Error )
tt_size_reset( TT_Size size );
/*************************************************************************/
/* */
/* Driver functions */
/* */
FT_LOCAL( FT_Error )
tt_driver_init( FT_Module ttdriver ); /* TT_Driver */
FT_LOCAL( void )
tt_driver_done( FT_Module ttdriver ); /* TT_Driver */
/*************************************************************************/
/* */
/* Slot functions */
/* */
FT_LOCAL( FT_Error )
tt_slot_init( FT_GlyphSlot slot );
/* auxiliary */
#define IS_HINTED( flags ) ( ( flags & FT_LOAD_NO_HINTING ) == 0 )
FT_END_HEADER
#endif /* __TTOBJS_H__ */
/* END */
|
