1 /****************************************************************************
2 *
3 * ttdriver.c
4 *
5 * TrueType font driver implementation (body).
6 *
7 * Copyright (C) 1996-2019 by
8 * David Turner, Robert Wilhelm, and Werner Lemberg.
9 *
10 * This file is part of the FreeType project, and may only be used,
11 * modified, and distributed under the terms of the FreeType project
12 * license, LICENSE.TXT. By continuing to use, modify, or distribute
13 * this file you indicate that you have read the license and
14 * understand and accept it fully.
15 *
16 */
17
18
19 #include <ft2build.h>
20 #include FT_INTERNAL_DEBUG_H
21 #include FT_INTERNAL_STREAM_H
22 #include FT_INTERNAL_SFNT_H
23 #include FT_SERVICE_FONT_FORMAT_H
24
25 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
26 #include FT_MULTIPLE_MASTERS_H
27 #include FT_SERVICE_MULTIPLE_MASTERS_H
28 #include FT_SERVICE_METRICS_VARIATIONS_H
29 #endif
30
31 #include FT_SERVICE_TRUETYPE_ENGINE_H
32 #include FT_SERVICE_TRUETYPE_GLYF_H
33 #include FT_SERVICE_PROPERTIES_H
34 #include FT_DRIVER_H
35
36 #include "ttdriver.h"
37 #include "ttgload.h"
38 #include "ttpload.h"
39
40 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
41 #include "ttgxvar.h"
42 #endif
43
44 #include "tterrors.h"
45
46
47 /**************************************************************************
48 *
49 * The macro FT_COMPONENT is used in trace mode. It is an implicit
50 * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
51 * messages during execution.
52 */
53 #undef FT_COMPONENT
54 #define FT_COMPONENT ttdriver
55
56
57 /*
58 * PROPERTY SERVICE
59 *
60 */
61 static FT_Error
62 tt_property_set( FT_Module module, /* TT_Driver */
63 const char* property_name,
64 const void* value,
65 FT_Bool value_is_string )
66 {
67 FT_Error error = FT_Err_Ok;
68 TT_Driver driver = (TT_Driver)module;
69
70 #ifndef FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES
71 FT_UNUSED( value_is_string );
72 #endif
73
74
75 if ( !ft_strcmp( property_name, "interpreter-version" ) )
76 {
77 FT_UInt interpreter_version;
78
79
80 #ifdef FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES
81 if ( value_is_string )
82 {
83 const char* s = (const char*)value;
84
85
86 interpreter_version = (FT_UInt)ft_strtol( s, NULL, 10 );
87 }
88 else
89 #endif
90 {
91 FT_UInt* iv = (FT_UInt*)value;
92
93
94 interpreter_version = *iv;
95 }
96
97 if ( interpreter_version == TT_INTERPRETER_VERSION_35
98 #ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
99 || interpreter_version == TT_INTERPRETER_VERSION_38
100 #endif
101 #ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
102 || interpreter_version == TT_INTERPRETER_VERSION_40
103 #endif
104 )
105 driver->interpreter_version = interpreter_version;
106 else
107 error = FT_ERR( Unimplemented_Feature );
108
109 return error;
110 }
111
112 FT_TRACE0(( "tt_property_set: missing property `%s'\n",
113 property_name ));
114 return FT_THROW( Missing_Property );
115 }
116
117
118 static FT_Error
119 tt_property_get( FT_Module module, /* TT_Driver */
120 const char* property_name,
121 const void* value )
122 {
123 FT_Error error = FT_Err_Ok;
124 TT_Driver driver = (TT_Driver)module;
125
126 FT_UInt interpreter_version = driver->interpreter_version;
127
128
129 if ( !ft_strcmp( property_name, "interpreter-version" ) )
130 {
131 FT_UInt* val = (FT_UInt*)value;
132
133
134 *val = interpreter_version;
135
136 return error;
137 }
138
139 FT_TRACE0(( "tt_property_get: missing property `%s'\n",
140 property_name ));
141 return FT_THROW( Missing_Property );
142 }
143
144
145 FT_DEFINE_SERVICE_PROPERTIESREC(
146 tt_service_properties,
147
148 (FT_Properties_SetFunc)tt_property_set, /* set_property */
149 (FT_Properties_GetFunc)tt_property_get /* get_property */
150 )
151
152
153 /*************************************************************************/
154 /*************************************************************************/
155 /*************************************************************************/
156 /**** ****/
157 /**** ****/
158 /**** F A C E S ****/
159 /**** ****/
160 /**** ****/
161 /*************************************************************************/
162 /*************************************************************************/
163 /*************************************************************************/
164
165
166 /**************************************************************************
167 *
168 * @Function:
169 * tt_get_kerning
170 *
171 * @Description:
172 * A driver method used to return the kerning vector between two
173 * glyphs of the same face.
174 *
175 * @Input:
176 * face ::
177 * A handle to the source face object.
178 *
179 * left_glyph ::
180 * The index of the left glyph in the kern pair.
181 *
182 * right_glyph ::
183 * The index of the right glyph in the kern pair.
184 *
185 * @Output:
186 * kerning ::
187 * The kerning vector. This is in font units for
188 * scalable formats, and in pixels for fixed-sizes
189 * formats.
190 *
191 * @Return:
192 * FreeType error code. 0 means success.
193 *
194 * @Note:
195 * Only horizontal layouts (left-to-right & right-to-left) are
196 * supported by this function. Other layouts, or more sophisticated
197 * kernings, are out of scope of this method (the basic driver
198 * interface is meant to be simple).
199 *
200 * They can be implemented by format-specific interfaces.
201 */
202 static FT_Error
203 tt_get_kerning( FT_Face ttface, /* TT_Face */
204 FT_UInt left_glyph,
205 FT_UInt right_glyph,
206 FT_Vector* kerning )
207 {
208 TT_Face face = (TT_Face)ttface;
209 SFNT_Service sfnt = (SFNT_Service)face->sfnt;
210
211
212 kerning->x = 0;
213 kerning->y = 0;
214
215 if ( sfnt )
216 kerning->x = sfnt->get_kerning( face, left_glyph, right_glyph );
217
218 return 0;
219 }
220
221
222 static FT_Error
223 tt_get_advances( FT_Face ttface,
224 FT_UInt start,
225 FT_UInt count,
226 FT_Int32 flags,
227 FT_Fixed *advances )
228 {
229 FT_UInt nn;
230 TT_Face face = (TT_Face)ttface;
231
232
233 /* XXX: TODO: check for sbits */
234
235 if ( flags & FT_LOAD_VERTICAL_LAYOUT )
236 {
237 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
238 /* no fast retrieval for blended MM fonts without VVAR table */
239 if ( ( FT_IS_NAMED_INSTANCE( ttface ) || FT_IS_VARIATION( ttface ) ) &&
240 !( face->variation_support & TT_FACE_FLAG_VAR_VADVANCE ) )
241 return FT_THROW( Unimplemented_Feature );
242 #endif
243
244 for ( nn = 0; nn < count; nn++ )
245 {
246 FT_Short tsb;
247 FT_UShort ah;
248
249
250 /* since we don't need `tsb', we use zero for `yMax' parameter */
251 TT_Get_VMetrics( face, start + nn, 0, &tsb, &ah );
252 advances[nn] = ah;
253 }
254 }
255 else
256 {
257 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
258 /* no fast retrieval for blended MM fonts without HVAR table */
259 if ( ( FT_IS_NAMED_INSTANCE( ttface ) || FT_IS_VARIATION( ttface ) ) &&
260 !( face->variation_support & TT_FACE_FLAG_VAR_HADVANCE ) )
261 return FT_THROW( Unimplemented_Feature );
262 #endif
263
264 for ( nn = 0; nn < count; nn++ )
265 {
266 FT_Short lsb;
267 FT_UShort aw;
268
269
270 TT_Get_HMetrics( face, start + nn, &lsb, &aw );
271 advances[nn] = aw;
272 }
273 }
274
275 return FT_Err_Ok;
276 }
277
278
279 /*************************************************************************/
280 /*************************************************************************/
281 /*************************************************************************/
282 /**** ****/
283 /**** ****/
284 /**** S I Z E S ****/
285 /**** ****/
286 /**** ****/
287 /*************************************************************************/
288 /*************************************************************************/
289 /*************************************************************************/
290
291
292 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
293
294 static FT_Error
295 tt_size_select( FT_Size size,
296 FT_ULong strike_index )
297 {
298 TT_Face ttface = (TT_Face)size->face;
299 TT_Size ttsize = (TT_Size)size;
300 FT_Error error = FT_Err_Ok;
301
302
303 ttsize->strike_index = strike_index;
304
305 if ( FT_IS_SCALABLE( size->face ) )
306 {
307 /* use the scaled metrics, even when tt_size_reset fails */
308 FT_Select_Metrics( size->face, strike_index );
309
310 tt_size_reset( ttsize, 0 ); /* ignore return value */
311 }
312 else
313 {
314 SFNT_Service sfnt = (SFNT_Service)ttface->sfnt;
315 FT_Size_Metrics* size_metrics = &size->metrics;
316
317
318 error = sfnt->load_strike_metrics( ttface,
319 strike_index,
320 size_metrics );
321 if ( error )
322 ttsize->strike_index = 0xFFFFFFFFUL;
323 }
324
325 return error;
326 }
327
328 #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
329
330
331 static FT_Error
332 tt_size_request( FT_Size size,
333 FT_Size_Request req )
334 {
335 TT_Size ttsize = (TT_Size)size;
336 FT_Error error = FT_Err_Ok;
337
338
339 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
340
341 if ( FT_HAS_FIXED_SIZES( size->face ) )
342 {
343 TT_Face ttface = (TT_Face)size->face;
344 SFNT_Service sfnt = (SFNT_Service)ttface->sfnt;
345 FT_ULong strike_index;
346
347
348 error = sfnt->set_sbit_strike( ttface, req, &strike_index );
349
350 if ( error )
351 ttsize->strike_index = 0xFFFFFFFFUL;
352 else
353 return tt_size_select( size, strike_index );
354 }
355
356 #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
357
358 FT_Request_Metrics( size->face, req );
359
360 if ( FT_IS_SCALABLE( size->face ) )
361 {
362 error = tt_size_reset( ttsize, 0 );
363
364 #ifdef TT_USE_BYTECODE_INTERPRETER
365 /* for the `MPS' bytecode instruction we need the point size */
366 if ( !error )
367 {
368 FT_UInt resolution =
369 ttsize->metrics->x_ppem > ttsize->metrics->y_ppem
370 ? req->horiResolution
371 : req->vertResolution;
372
373
374 /* if we don't have a resolution value, assume 72dpi */
375 if ( req->type == FT_SIZE_REQUEST_TYPE_SCALES ||
376 !resolution )
377 resolution = 72;
378
379 ttsize->point_size = FT_MulDiv( ttsize->ttmetrics.ppem,
380 64 * 72,
381 resolution );
382 }
383 #endif
384 }
385
386 return error;
387 }
388
389
390 /**************************************************************************
391 *
392 * @Function:
393 * tt_glyph_load
394 *
395 * @Description:
396 * A driver method used to load a glyph within a given glyph slot.
397 *
398 * @Input:
399 * slot ::
400 * A handle to the target slot object where the glyph
401 * will be loaded.
402 *
403 * size ::
404 * A handle to the source face size at which the glyph
405 * must be scaled, loaded, etc.
406 *
407 * glyph_index ::
408 * The index of the glyph in the font file.
409 *
410 * load_flags ::
411 * A flag indicating what to load for this glyph. The
412 * FT_LOAD_XXX constants can be used to control the
413 * glyph loading process (e.g., whether the outline
414 * should be scaled, whether to load bitmaps or not,
415 * whether to hint the outline, etc).
416 *
417 * @Return:
418 * FreeType error code. 0 means success.
419 */
420 static FT_Error
421 tt_glyph_load( FT_GlyphSlot ttslot, /* TT_GlyphSlot */
422 FT_Size ttsize, /* TT_Size */
423 FT_UInt glyph_index,
424 FT_Int32 load_flags )
425 {
426 TT_GlyphSlot slot = (TT_GlyphSlot)ttslot;
427 TT_Size size = (TT_Size)ttsize;
428 FT_Face face = ttslot->face;
429 FT_Error error;
430
431
432 if ( !slot )
433 return FT_THROW( Invalid_Slot_Handle );
434
435 if ( !size )
436 return FT_THROW( Invalid_Size_Handle );
437
438 if ( !face )
439 return FT_THROW( Invalid_Face_Handle );
440
441 #ifdef FT_CONFIG_OPTION_INCREMENTAL
442 if ( glyph_index >= (FT_UInt)face->num_glyphs &&
443 !face->internal->incremental_interface )
444 #else
445 if ( glyph_index >= (FT_UInt)face->num_glyphs )
446 #endif
447 return FT_THROW( Invalid_Argument );
448
449 if ( load_flags & FT_LOAD_NO_HINTING )
450 {
451 /* both FT_LOAD_NO_HINTING and FT_LOAD_NO_AUTOHINT */
452 /* are necessary to disable hinting for tricky fonts */
453
454 if ( FT_IS_TRICKY( face ) )
455 load_flags &= ~FT_LOAD_NO_HINTING;
456
457 if ( load_flags & FT_LOAD_NO_AUTOHINT )
458 load_flags |= FT_LOAD_NO_HINTING;
459 }
460
461 if ( load_flags & ( FT_LOAD_NO_RECURSE | FT_LOAD_NO_SCALE ) )
462 {
463 load_flags |= FT_LOAD_NO_BITMAP | FT_LOAD_NO_SCALE;
464
465 if ( !FT_IS_TRICKY( face ) )
466 load_flags |= FT_LOAD_NO_HINTING;
467 }
468
469 /* use hinted metrics only if we load a glyph with hinting */
470 size->metrics = ( load_flags & FT_LOAD_NO_HINTING )
471 ? &ttsize->metrics
472 : &size->hinted_metrics;
473
474 /* now fill in the glyph slot with outline/bitmap/layered */
475 error = TT_Load_Glyph( size, slot, glyph_index, load_flags );
476
477 /* force drop-out mode to 2 - irrelevant now */
478 /* slot->outline.dropout_mode = 2; */
479
480 return error;
481 }
482
483
484 /*************************************************************************/
485 /*************************************************************************/
486 /*************************************************************************/
487 /**** ****/
488 /**** ****/
489 /**** D R I V E R I N T E R F A C E ****/
490 /**** ****/
491 /**** ****/
492 /*************************************************************************/
493 /*************************************************************************/
494 /*************************************************************************/
495
496 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
497
498 FT_DEFINE_SERVICE_MULTIMASTERSREC(
499 tt_service_gx_multi_masters,
500
501 (FT_Get_MM_Func) NULL, /* get_mm */
502 (FT_Set_MM_Design_Func) NULL, /* set_mm_design */
503 (FT_Set_MM_Blend_Func) TT_Set_MM_Blend, /* set_mm_blend */
504 (FT_Get_MM_Blend_Func) TT_Get_MM_Blend, /* get_mm_blend */
505 (FT_Get_MM_Var_Func) TT_Get_MM_Var, /* get_mm_var */
506 (FT_Set_Var_Design_Func) TT_Set_Var_Design, /* set_var_design */
507 (FT_Get_Var_Design_Func) TT_Get_Var_Design, /* get_var_design */
508 (FT_Set_Instance_Func) TT_Set_Named_Instance, /* set_instance */
509 (FT_Set_MM_WeightVector_Func)NULL, /* set_mm_weightvector */
510 (FT_Get_MM_WeightVector_Func)NULL, /* get_mm_weightvector */
511
512 (FT_Get_Var_Blend_Func) tt_get_var_blend, /* get_var_blend */
513 (FT_Done_Blend_Func) tt_done_blend /* done_blend */
514 )
515
516 FT_DEFINE_SERVICE_METRICSVARIATIONSREC(
517 tt_service_metrics_variations,
518
519 (FT_HAdvance_Adjust_Func)tt_hadvance_adjust, /* hadvance_adjust */
520 (FT_LSB_Adjust_Func) NULL, /* lsb_adjust */
521 (FT_RSB_Adjust_Func) NULL, /* rsb_adjust */
522
523 (FT_VAdvance_Adjust_Func)tt_vadvance_adjust, /* vadvance_adjust */
524 (FT_TSB_Adjust_Func) NULL, /* tsb_adjust */
525 (FT_BSB_Adjust_Func) NULL, /* bsb_adjust */
526 (FT_VOrg_Adjust_Func) NULL, /* vorg_adjust */
527
528 (FT_Metrics_Adjust_Func) tt_apply_mvar /* metrics_adjust */
529 )
530
531 #endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
532
533
534 static const FT_Service_TrueTypeEngineRec tt_service_truetype_engine =
535 {
536 #ifdef TT_USE_BYTECODE_INTERPRETER
537
538 FT_TRUETYPE_ENGINE_TYPE_PATENTED
539
540 #else /* !TT_USE_BYTECODE_INTERPRETER */
541
542 FT_TRUETYPE_ENGINE_TYPE_NONE
543
544 #endif /* TT_USE_BYTECODE_INTERPRETER */
545 };
546
547
548 FT_DEFINE_SERVICE_TTGLYFREC(
549 tt_service_truetype_glyf,
550
551 (TT_Glyf_GetLocationFunc)tt_face_get_location /* get_location */
552 )
553
554
555 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
556 FT_DEFINE_SERVICEDESCREC6(
557 tt_services,
558
559 FT_SERVICE_ID_FONT_FORMAT, FT_FONT_FORMAT_TRUETYPE,
560 FT_SERVICE_ID_MULTI_MASTERS, &tt_service_gx_multi_masters,
561 FT_SERVICE_ID_METRICS_VARIATIONS, &tt_service_metrics_variations,
562 FT_SERVICE_ID_TRUETYPE_ENGINE, &tt_service_truetype_engine,
563 FT_SERVICE_ID_TT_GLYF, &tt_service_truetype_glyf,
564 FT_SERVICE_ID_PROPERTIES, &tt_service_properties )
565 #else
566 FT_DEFINE_SERVICEDESCREC4(
567 tt_services,
568
569 FT_SERVICE_ID_FONT_FORMAT, FT_FONT_FORMAT_TRUETYPE,
570 FT_SERVICE_ID_TRUETYPE_ENGINE, &tt_service_truetype_engine,
571 FT_SERVICE_ID_TT_GLYF, &tt_service_truetype_glyf,
572 FT_SERVICE_ID_PROPERTIES, &tt_service_properties )
573 #endif
574
575
576 FT_CALLBACK_DEF( FT_Module_Interface )
577 tt_get_interface( FT_Module driver, /* TT_Driver */
578 const char* tt_interface )
579 {
580 FT_Library library;
581 FT_Module_Interface result;
582 FT_Module sfntd;
583 SFNT_Service sfnt;
584
585
586 result = ft_service_list_lookup( tt_services, tt_interface );
587 if ( result )
588 return result;
589
590 if ( !driver )
591 return NULL;
592 library = driver->library;
593 if ( !library )
594 return NULL;
595
596 /* only return the default interface from the SFNT module */
597 sfntd = FT_Get_Module( library, "sfnt" );
598 if ( sfntd )
599 {
600 sfnt = (SFNT_Service)( sfntd->clazz->module_interface );
601 if ( sfnt )
602 return sfnt->get_interface( driver, tt_interface );
603 }
604
605 return 0;
606 }
607
608
609 /* The FT_DriverInterface structure is defined in ftdriver.h. */
610
611 #ifdef TT_USE_BYTECODE_INTERPRETER
612 #define TT_HINTER_FLAG FT_MODULE_DRIVER_HAS_HINTER
613 #else
614 #define TT_HINTER_FLAG 0
615 #endif
616
617 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
618 #define TT_SIZE_SELECT tt_size_select
619 #else
620 #define TT_SIZE_SELECT 0
621 #endif
622
623 FT_DEFINE_DRIVER(
624 tt_driver_class,
625
626 FT_MODULE_FONT_DRIVER |
627 FT_MODULE_DRIVER_SCALABLE |
628 TT_HINTER_FLAG,
629
630 sizeof ( TT_DriverRec ),
631
632 "truetype", /* driver name */
633 0x10000L, /* driver version == 1.0 */
634 0x20000L, /* driver requires FreeType 2.0 or above */
635
636 NULL, /* module-specific interface */
637
638 tt_driver_init, /* FT_Module_Constructor module_init */
639 tt_driver_done, /* FT_Module_Destructor module_done */
640 tt_get_interface, /* FT_Module_Requester get_interface */
641
642 sizeof ( TT_FaceRec ),
643 sizeof ( TT_SizeRec ),
644 sizeof ( FT_GlyphSlotRec ),
645
646 tt_face_init, /* FT_Face_InitFunc init_face */
647 tt_face_done, /* FT_Face_DoneFunc done_face */
648 tt_size_init, /* FT_Size_InitFunc init_size */
649 tt_size_done, /* FT_Size_DoneFunc done_size */
650 tt_slot_init, /* FT_Slot_InitFunc init_slot */
651 NULL, /* FT_Slot_DoneFunc done_slot */
652
653 tt_glyph_load, /* FT_Slot_LoadFunc load_glyph */
654
655 tt_get_kerning, /* FT_Face_GetKerningFunc get_kerning */
656 NULL, /* FT_Face_AttachFunc attach_file */
657 tt_get_advances, /* FT_Face_GetAdvancesFunc get_advances */
658
659 tt_size_request, /* FT_Size_RequestFunc request_size */
660 TT_SIZE_SELECT /* FT_Size_SelectFunc select_size */
661 )
662
663
664 /* END */