2 * Copyright (C) 2006 Evgeniy Stepanov <eugeni.stepanov@gmail.com>
4 * This file is part of libass.
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
23 #include FT_FREETYPE_H
24 #include FT_SYNTHESIS_H
26 #include FT_TRUETYPE_TABLES_H
31 #include "ass_library.h"
33 #include "ass_fontconfig.h"
34 #include "ass_utils.h"
36 #define VERTICAL_LOWER_BOUND 0x02f1
39 * Select a good charmap, prefer Microsoft Unicode charmaps.
40 * Otherwise, let FreeType decide.
42 static void charmap_magic(ASS_Library
*library
, FT_Face face
)
47 // Search for a Microsoft Unicode cmap
48 for (i
= 0; i
< face
->num_charmaps
; ++i
) {
49 FT_CharMap cmap
= face
->charmaps
[i
];
50 unsigned pid
= cmap
->platform_id
;
51 unsigned eid
= cmap
->encoding_id
;
52 if (pid
== 3 /*microsoft */
53 && (eid
== 1 /*unicode bmp */
54 || eid
== 10 /*full unicode */ )) {
55 FT_Set_Charmap(face
, cmap
);
57 } else if (pid
== 3 && ms_cmap
< 0)
61 // Try the first Microsoft cmap if no Microsoft Unicode cmap was found
63 FT_CharMap cmap
= face
->charmaps
[ms_cmap
];
64 FT_Set_Charmap(face
, cmap
);
69 if (face
->num_charmaps
== 0) {
70 ass_msg(library
, MSGL_WARN
, "Font face with no charmaps");
73 ass_msg(library
, MSGL_WARN
,
74 "No charmap autodetected, trying the first one");
75 FT_Set_Charmap(face
, face
->charmaps
[0]);
81 * \brief find a memory font by name
83 static int find_font(ASS_Library
*library
, char *name
)
86 for (i
= 0; i
< library
->num_fontdata
; ++i
)
87 if (strcasecmp(name
, library
->fontdata
[i
].name
) == 0)
92 static void face_set_size(FT_Face face
, double size
);
94 static void buggy_font_workaround(FT_Face face
)
96 // Some fonts have zero Ascender/Descender fields in 'hhea' table.
97 // In this case, get the information from 'os2' table or, as
98 // a last resort, from face.bbox.
99 if (face
->ascender
+ face
->descender
== 0 || face
->height
== 0) {
100 TT_OS2
*os2
= FT_Get_Sfnt_Table(face
, ft_sfnt_os2
);
102 face
->ascender
= os2
->sTypoAscender
;
103 face
->descender
= os2
->sTypoDescender
;
104 face
->height
= face
->ascender
- face
->descender
;
106 face
->ascender
= face
->bbox
.yMax
;
107 face
->descender
= face
->bbox
.yMin
;
108 face
->height
= face
->ascender
- face
->descender
;
114 * \brief Select a face with the given charcode and add it to ASS_Font
115 * \return index of the new face in font->faces, -1 if failed
117 static int add_face(void *fc_priv
, ASS_Font
*font
, uint32_t ch
)
125 if (font
->n_faces
== ASS_FONT_MAX_FACES
)
129 fontconfig_select(font
->library
, fc_priv
, font
->desc
.family
,
130 font
->desc
.treat_family_as_pattern
,
131 font
->desc
.bold
, font
->desc
.italic
, &index
, ch
);
135 mem_idx
= find_font(font
->library
, path
);
138 FT_New_Memory_Face(font
->ftlibrary
,
139 (unsigned char *) font
->library
->
140 fontdata
[mem_idx
].data
,
141 font
->library
->fontdata
[mem_idx
].size
, index
,
144 ass_msg(font
->library
, MSGL_WARN
,
145 "Error opening memory font: '%s'", path
);
150 error
= FT_New_Face(font
->ftlibrary
, path
, index
, &face
);
152 ass_msg(font
->library
, MSGL_WARN
,
153 "Error opening font: '%s', %d", path
, index
);
158 charmap_magic(font
->library
, face
);
159 buggy_font_workaround(face
);
161 font
->faces
[font
->n_faces
++] = face
;
162 face_set_size(face
, font
->size
);
164 return font
->n_faces
- 1;
168 * \brief Create a new ASS_Font according to "desc" argument
170 ASS_Font
*ass_font_new(Cache
*font_cache
, ASS_Library
*library
,
171 FT_Library ftlibrary
, void *fc_priv
,
178 fontp
= ass_cache_get(font_cache
, desc
);
182 font
.library
= library
;
183 font
.ftlibrary
= ftlibrary
;
185 font
.desc
.family
= strdup(desc
->family
);
186 font
.desc
.treat_family_as_pattern
= desc
->treat_family_as_pattern
;
187 font
.desc
.bold
= desc
->bold
;
188 font
.desc
.italic
= desc
->italic
;
189 font
.desc
.vertical
= desc
->vertical
;
191 font
.scale_x
= font
.scale_y
= 1.;
192 font
.v
.x
= font
.v
.y
= 0;
195 error
= add_face(fc_priv
, &font
, 0);
197 free(font
.desc
.family
);
200 return ass_cache_put(font_cache
, &font
.desc
, &font
);
204 * \brief Set font transformation matrix and shift vector
206 void ass_font_set_transform(ASS_Font
*font
, double scale_x
,
207 double scale_y
, FT_Vector
*v
)
209 font
->scale_x
= scale_x
;
210 font
->scale_y
= scale_y
;
217 static void face_set_size(FT_Face face
, double size
)
219 TT_HoriHeader
*hori
= FT_Get_Sfnt_Table(face
, ft_sfnt_hhea
);
220 TT_OS2
*os2
= FT_Get_Sfnt_Table(face
, ft_sfnt_os2
);
222 FT_Size_RequestRec rq
;
223 FT_Size_Metrics
*m
= &face
->size
->metrics
;
224 // VSFilter uses metrics from TrueType OS/2 table
225 // The idea was borrowed from asa (http://asa.diac24.net)
227 int hori_height
= hori
->Ascender
- hori
->Descender
;
228 int os2_height
= os2
->usWinAscent
+ os2
->usWinDescent
;
229 if (hori_height
&& os2_height
)
230 mscale
= (double) hori_height
/ os2_height
;
232 memset(&rq
, 0, sizeof(rq
));
233 rq
.type
= FT_SIZE_REQUEST_TYPE_REAL_DIM
;
235 rq
.height
= double_to_d6(size
* mscale
);
236 rq
.horiResolution
= rq
.vertResolution
= 0;
237 FT_Request_Size(face
, &rq
);
238 m
->ascender
/= mscale
;
239 m
->descender
/= mscale
;
244 * \brief Set font size
246 void ass_font_set_size(ASS_Font
*font
, double size
)
249 if (font
->size
!= size
) {
251 for (i
= 0; i
< font
->n_faces
; ++i
)
252 face_set_size(font
->faces
[i
], size
);
257 * \brief Get maximal font ascender and descender.
258 * \param ch character code
259 * The values are extracted from the font face that provides glyphs for the given character
261 void ass_font_get_asc_desc(ASS_Font
*font
, uint32_t ch
, int *asc
,
265 for (i
= 0; i
< font
->n_faces
; ++i
) {
266 FT_Face face
= font
->faces
[i
];
267 TT_OS2
*os2
= FT_Get_Sfnt_Table(face
, ft_sfnt_os2
);
268 if (FT_Get_Char_Index(face
, ch
)) {
269 int y_scale
= face
->size
->metrics
.y_scale
;
271 *asc
= FT_MulFix(os2
->usWinAscent
, y_scale
);
272 *desc
= FT_MulFix(os2
->usWinDescent
, y_scale
);
274 *asc
= FT_MulFix(face
->ascender
, y_scale
);
275 *desc
= FT_MulFix(-face
->descender
, y_scale
);
277 if (font
->desc
.vertical
&& ch
>= VERTICAL_LOWER_BOUND
) {
278 *asc
= FT_MulFix(face
->max_advance_width
, y_scale
);
288 * Strike a glyph with a horizontal line; it's possible to underline it
289 * and/or strike through it. For the line's position and size, truetype
290 * tables are consulted. Obviously this relies on the data in the tables
294 static int ass_strike_outline_glyph(FT_Face face
, ASS_Font
*font
,
295 FT_Glyph glyph
, int under
, int through
)
297 TT_OS2
*os2
= FT_Get_Sfnt_Table(face
, ft_sfnt_os2
);
298 TT_Postscript
*ps
= FT_Get_Sfnt_Table(face
, ft_sfnt_post
);
299 FT_Outline
*ol
= &((FT_OutlineGlyph
) glyph
)->outline
;
300 int bear
, advance
, y_scale
, i
, dir
;
302 if (!under
&& !through
)
306 i
= (under
? 4 : 0) + (through
? 4 : 0);
307 ol
->points
= realloc(ol
->points
, sizeof(FT_Vector
) *
309 ol
->tags
= realloc(ol
->tags
, ol
->n_points
+ i
);
310 i
= !!under
+ !!through
;
311 ol
->contours
= realloc(ol
->contours
, sizeof(short) *
312 (ol
->n_contours
+ i
));
314 // If the bearing is negative, the glyph starts left of the current
316 bear
= FFMIN(face
->glyph
->metrics
.horiBearingX
, 0);
317 // We're adding half a pixel to avoid small gaps
318 advance
= d16_to_d6(glyph
->advance
.x
) + 32;
319 y_scale
= face
->size
->metrics
.y_scale
;
321 // Reverse drawing direction for non-truetype fonts
322 dir
= FT_Outline_Get_Orientation(ol
);
324 // Add points to the outline
327 pos
= FT_MulFix(ps
->underlinePosition
, y_scale
* font
->scale_y
);
328 size
= FT_MulFix(ps
->underlineThickness
,
329 y_scale
* font
->scale_y
/ 2);
331 if (pos
> 0 || size
<= 0)
334 FT_Vector points
[4] = {
335 {.x
= bear
, .y
= pos
+ size
},
336 {.x
= advance
, .y
= pos
+ size
},
337 {.x
= advance
, .y
= pos
- size
},
338 {.x
= bear
, .y
= pos
- size
},
341 if (dir
== FT_ORIENTATION_TRUETYPE
) {
342 for (i
= 0; i
< 4; i
++) {
343 ol
->points
[ol
->n_points
] = points
[i
];
344 ol
->tags
[ol
->n_points
++] = 1;
347 for (i
= 3; i
>= 0; i
--) {
348 ol
->points
[ol
->n_points
] = points
[i
];
349 ol
->tags
[ol
->n_points
++] = 1;
353 ol
->contours
[ol
->n_contours
++] = ol
->n_points
- 1;
356 if (through
&& os2
) {
358 pos
= FT_MulFix(os2
->yStrikeoutPosition
, y_scale
* font
->scale_y
);
359 size
= FT_MulFix(os2
->yStrikeoutSize
, y_scale
* font
->scale_y
/ 2);
361 if (pos
< 0 || size
<= 0)
364 FT_Vector points
[4] = {
365 {.x
= bear
, .y
= pos
+ size
},
366 {.x
= advance
, .y
= pos
+ size
},
367 {.x
= advance
, .y
= pos
- size
},
368 {.x
= bear
, .y
= pos
- size
},
371 if (dir
== FT_ORIENTATION_TRUETYPE
) {
372 for (i
= 0; i
< 4; i
++) {
373 ol
->points
[ol
->n_points
] = points
[i
];
374 ol
->tags
[ol
->n_points
++] = 1;
377 for (i
= 3; i
>= 0; i
--) {
378 ol
->points
[ol
->n_points
] = points
[i
];
379 ol
->tags
[ol
->n_points
++] = 1;
383 ol
->contours
[ol
->n_contours
++] = ol
->n_points
- 1;
389 void outline_copy(FT_Library lib
, FT_Outline
*source
, FT_Outline
**dest
)
391 if (source
== NULL
) {
395 *dest
= calloc(1, sizeof(**dest
));
397 FT_Outline_New(lib
, source
->n_points
, source
->n_contours
, *dest
);
398 FT_Outline_Copy(source
, *dest
);
401 void outline_free(FT_Library lib
, FT_Outline
*outline
)
404 FT_Outline_Done(lib
, outline
);
409 * Slightly embold a glyph without touching its metrics
411 static void ass_glyph_embolden(FT_GlyphSlot slot
)
415 if (slot
->format
!= FT_GLYPH_FORMAT_OUTLINE
)
418 str
= FT_MulFix(slot
->face
->units_per_EM
,
419 slot
->face
->size
->metrics
.y_scale
) / 64;
421 FT_Outline_Embolden(&slot
->outline
, str
);
425 * \brief Get glyph and face index
426 * Finds a face that has the requested codepoint and returns both face
429 int ass_font_get_index(void *fcpriv
, ASS_Font
*font
, uint32_t symbol
,
430 int *face_index
, int *glyph_index
)
442 // Handle NBSP like a regular space when rendering the glyph
445 if (font
->n_faces
== 0) {
450 // try with the requested face
451 if (*face_index
< font
->n_faces
) {
452 face
= font
->faces
[i
];
453 index
= FT_Get_Char_Index(face
, symbol
);
456 // not found in requested face, try all others
457 for (i
= 0; i
< font
->n_faces
&& index
== 0; ++i
) {
458 face
= font
->faces
[i
];
459 index
= FT_Get_Char_Index(face
, symbol
);
464 #ifdef CONFIG_FONTCONFIG
467 ass_msg(font
->library
, MSGL_INFO
,
468 "Glyph 0x%X not found, selecting one more "
469 "font for (%s, %d, %d)", symbol
, font
->desc
.family
,
470 font
->desc
.bold
, font
->desc
.italic
);
471 face_idx
= *face_index
= add_face(fcpriv
, font
, symbol
);
473 face
= font
->faces
[face_idx
];
474 index
= FT_Get_Char_Index(face
, symbol
);
475 if (index
== 0 && face
->num_charmaps
> 0) {
477 ass_msg(font
->library
, MSGL_WARN
,
478 "Glyph 0x%X not found, broken font? Trying all charmaps", symbol
);
479 for (i
= 0; i
< face
->num_charmaps
; i
++) {
480 FT_Set_Charmap(face
, face
->charmaps
[i
]);
481 if ((index
= FT_Get_Char_Index(face
, symbol
)) != 0) break;
485 ass_msg(font
->library
, MSGL_ERR
,
486 "Glyph 0x%X not found in font for (%s, %d, %d)",
487 symbol
, font
->desc
.family
, font
->desc
.bold
,
493 *glyph_index
= index
;
500 * \param ch character code
502 FT_Glyph
ass_font_get_glyph(void *fontconfig_priv
, ASS_Font
*font
,
503 uint32_t ch
, int face_index
, int index
,
504 ASS_Hinting hinting
, int deco
)
508 FT_Face face
= font
->faces
[face_index
];
510 int vertical
= font
->desc
.vertical
;
512 flags
= FT_LOAD_NO_BITMAP
| FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH
513 | FT_LOAD_IGNORE_TRANSFORM
;
515 case ASS_HINTING_NONE
:
516 flags
|= FT_LOAD_NO_HINTING
;
518 case ASS_HINTING_LIGHT
:
519 flags
|= FT_LOAD_FORCE_AUTOHINT
| FT_LOAD_TARGET_LIGHT
;
521 case ASS_HINTING_NORMAL
:
522 flags
|= FT_LOAD_FORCE_AUTOHINT
;
524 case ASS_HINTING_NATIVE
:
528 error
= FT_Load_Glyph(face
, index
, flags
);
530 ass_msg(font
->library
, MSGL_WARN
, "Error loading glyph, index %d",
534 if (!(face
->style_flags
& FT_STYLE_FLAG_ITALIC
) &&
535 (font
->desc
.italic
> 55)) {
536 FT_GlyphSlot_Oblique(face
->glyph
);
539 if (!(face
->style_flags
& FT_STYLE_FLAG_BOLD
) &&
540 (font
->desc
.bold
> 80)) {
541 ass_glyph_embolden(face
->glyph
);
543 error
= FT_Get_Glyph(face
->glyph
, &glyph
);
545 ass_msg(font
->library
, MSGL_WARN
, "Error loading glyph, index %d",
550 // Rotate glyph, if needed
551 if (vertical
&& ch
>= VERTICAL_LOWER_BOUND
) {
552 FT_Matrix m
= { 0, double_to_d16(-1.0), double_to_d16(1.0), 0 };
553 FT_Outline_Transform(&((FT_OutlineGlyph
) glyph
)->outline
, &m
);
554 FT_Outline_Translate(&((FT_OutlineGlyph
) glyph
)->outline
,
555 face
->glyph
->metrics
.vertAdvance
,
557 glyph
->advance
.x
= face
->glyph
->linearVertAdvance
;
560 // Apply scaling and shift
561 FT_Matrix scale
= { double_to_d16(font
->scale_x
), 0, 0,
562 double_to_d16(font
->scale_y
) };
563 FT_Outline
*outl
= &((FT_OutlineGlyph
) glyph
)->outline
;
564 FT_Outline_Transform(outl
, &scale
);
565 FT_Outline_Translate(outl
, font
->v
.x
, font
->v
.y
);
566 glyph
->advance
.x
*= font
->scale_x
;
568 ass_strike_outline_glyph(face
, font
, glyph
, deco
& DECO_UNDERLINE
,
569 deco
& DECO_STRIKETHROUGH
);
575 * \brief Get kerning for the pair of glyphs.
577 FT_Vector
ass_font_get_kerning(ASS_Font
*font
, uint32_t c1
, uint32_t c2
)
579 FT_Vector v
= { 0, 0 };
582 if (font
->desc
.vertical
)
585 for (i
= 0; i
< font
->n_faces
; ++i
) {
586 FT_Face face
= font
->faces
[i
];
587 int i1
= FT_Get_Char_Index(face
, c1
);
588 int i2
= FT_Get_Char_Index(face
, c2
);
590 if (FT_HAS_KERNING(face
))
591 FT_Get_Kerning(face
, i1
, i2
, FT_KERNING_DEFAULT
, &v
);
594 if (i1
|| i2
) // these glyphs are from different font faces, no kerning information
601 * \brief Deallocate ASS_Font
603 void ass_font_free(ASS_Font
*font
)
606 for (i
= 0; i
< font
->n_faces
; ++i
)
608 FT_Done_Face(font
->faces
[i
]);
609 free(font
->desc
.family
);
614 * \brief Calculate the cbox of a series of points
617 get_contour_cbox(FT_BBox
*box
, FT_Vector
*points
, int start
, int end
)
619 box
->xMin
= box
->yMin
= INT_MAX
;
620 box
->xMax
= box
->yMax
= INT_MIN
;
623 for (i
= start
; i
<= end
; i
++) {
624 box
->xMin
= (points
[i
].x
< box
->xMin
) ? points
[i
].x
: box
->xMin
;
625 box
->xMax
= (points
[i
].x
> box
->xMax
) ? points
[i
].x
: box
->xMax
;
626 box
->yMin
= (points
[i
].y
< box
->yMin
) ? points
[i
].y
: box
->yMin
;
627 box
->yMax
= (points
[i
].y
> box
->yMax
) ? points
[i
].y
: box
->yMax
;
632 * \brief Determine winding direction of a contour
633 * \return direction; 0 = clockwise
635 static int get_contour_direction(FT_Vector
*points
, int start
, int end
)
639 int x
= points
[start
].x
;
640 int y
= points
[start
].y
;
641 for (i
= start
+ 1; i
<= end
; i
++) {
642 sum
+= x
* (points
[i
].y
- y
) - y
* (points
[i
].x
- x
);
646 sum
+= x
* (points
[start
].y
- y
) - y
* (points
[start
].x
- x
);
651 * \brief Fix-up stroker result for huge borders by removing inside contours
652 * that would reverse in size
654 void fix_freetype_stroker(FT_Outline
*outline
, int border_x
, int border_y
)
656 int nc
= outline
->n_contours
;
659 char *valid_cont
= malloc(nc
);
662 FT_BBox
*boxes
= malloc(nc
* sizeof(FT_BBox
));
664 int inside_direction
;
666 inside_direction
= FT_Outline_Get_Orientation(outline
) ==
667 FT_ORIENTATION_TRUETYPE
;
669 // create a list of cboxes of the contours
670 for (i
= 0; i
< nc
; i
++) {
672 end
= outline
->contours
[i
];
673 get_contour_cbox(&boxes
[i
], outline
->points
, start
, end
);
676 // for each contour, check direction and whether it's "outside"
677 // or contained in another contour
679 for (i
= 0; i
< nc
; i
++) {
681 end
= outline
->contours
[i
];
682 int dir
= get_contour_direction(outline
->points
, start
, end
);
684 if (dir
== inside_direction
) {
685 for (j
= 0; j
< nc
; j
++) {
688 if (boxes
[i
].xMin
>= boxes
[j
].xMin
&&
689 boxes
[i
].xMax
<= boxes
[j
].xMax
&&
690 boxes
[i
].yMin
>= boxes
[j
].yMin
&&
691 boxes
[i
].yMax
<= boxes
[j
].yMax
)
694 /* "inside" contour but we can't find anything it could be
695 * inside of - assume the font is buggy and it should be
696 * an "outside" contour, and reverse it */
697 for (j
= 0; j
< (end
+ 1 - start
) / 2; j
++) {
698 FT_Vector temp
= outline
->points
[start
+ j
];
699 char temp2
= outline
->tags
[start
+ j
];
700 outline
->points
[start
+ j
] = outline
->points
[end
- j
];
701 outline
->points
[end
- j
] = temp
;
702 outline
->tags
[start
+ j
] = outline
->tags
[end
- j
];
703 outline
->tags
[end
- j
] = temp2
;
708 if (dir
== inside_direction
) {
710 get_contour_cbox(&box
, outline
->points
, start
, end
);
711 int width
= box
.xMax
- box
.xMin
;
712 int height
= box
.yMax
- box
.yMin
;
713 if (width
< border_x
* 2 || height
< border_y
* 2) {
720 // zero-out contours that can be removed; much simpler than copying
722 for (i
= 0; i
< nc
; i
++) {
725 begin
= (i
== 0) ? 0 : outline
->contours
[i
- 1] + 1;
726 stop
= outline
->contours
[i
];
727 for (j
= begin
; j
<= stop
; j
++) {
728 outline
->points
[j
].x
= 0;
729 outline
->points
[j
].y
= 0;
730 outline
->tags
[j
] = 0;