2 * Copyright (C) 2006 Evgeniy Stepanov <eugeni.stepanov@gmail.com>
4 * This file is part of libass.
6 * libass is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * libass is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License along
17 * with libass; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
25 #include FT_FREETYPE_H
26 #include FT_SYNTHESIS_H
28 #include FT_TRUETYPE_TABLES_H
31 #include "ass_library.h"
33 #include "ass_bitmap.h"
34 #include "ass_cache.h"
35 #include "ass_fontconfig.h"
36 #include "ass_utils.h"
39 * Select Microfost Unicode CharMap, if the font has one.
40 * Otherwise, let FreeType decide.
42 static void charmap_magic(ass_library_t *library, FT_Face face)
45 for (i = 0; i < face->num_charmaps; ++i) {
46 FT_CharMap cmap = face->charmaps[i];
47 unsigned pid = cmap->platform_id;
48 unsigned eid = cmap->encoding_id;
49 if (pid == 3 /*microsoft */
50 && (eid == 1 /*unicode bmp */
51 || eid == 10 /*full unicode */ )) {
52 FT_Set_Charmap(face, cmap);
58 if (face->num_charmaps == 0) {
59 ass_msg(library, MSGL_WARN, "Font face with no charmaps");
62 ass_msg(library, MSGL_WARN,
63 "No charmap autodetected, trying the first one");
64 FT_Set_Charmap(face, face->charmaps[0]);
69 static void update_transform(ass_font_t *font)
73 m.xx = double_to_d16(font->scale_x);
74 m.yy = double_to_d16(font->scale_y);
76 for (i = 0; i < font->n_faces; ++i)
77 FT_Set_Transform(font->faces[i], &m, &font->v);
81 * \brief find a memory font by name
83 static int find_font(ass_library_t *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_t
115 * \return index of the new face in font->faces, -1 if failed
117 static int add_face(void *fc_priv, ass_font_t *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, 0,
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 update_transform(font);
163 face_set_size(face, font->size);
165 return font->n_faces - 1;
169 * \brief Create a new ass_font_t according to "desc" argument
171 ass_font_t *ass_font_new(void *font_cache, ass_library_t *library,
172 FT_Library ftlibrary, void *fc_priv,
173 ass_font_desc_t *desc)
179 fontp = ass_font_cache_find((hashmap_t *) font_cache, desc);
183 font.library = library;
184 font.ftlibrary = ftlibrary;
186 font.desc.family = strdup(desc->family);
187 font.desc.treat_family_as_pattern = desc->treat_family_as_pattern;
188 font.desc.bold = desc->bold;
189 font.desc.italic = desc->italic;
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_font_cache_add((hashmap_t *) font_cache, &font);
204 * \brief Set font transformation matrix and shift vector
206 void ass_font_set_transform(ass_font_t *font, double scale_x,
207 double scale_y, FT_Vector *v)
209 font->scale_x = scale_x;
210 font->scale_y = scale_y;
213 update_transform(font);
216 static void face_set_size(FT_Face face, double size)
218 #if (FREETYPE_MAJOR > 2) || ((FREETYPE_MAJOR == 2) && (FREETYPE_MINOR > 1))
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;
242 FT_Set_Char_Size(face, 0, double_to_d6(size), 0, 0);
247 * \brief Set font size
249 void ass_font_set_size(ass_font_t *font, double size)
252 if (font->size != size) {
254 for (i = 0; i < font->n_faces; ++i)
255 face_set_size(font->faces[i], size);
260 * \brief Get maximal font ascender and descender.
261 * \param ch character code
262 * The values are extracted from the font face that provides glyphs for the given character
264 void ass_font_get_asc_desc(ass_font_t *font, uint32_t ch, int *asc,
268 for (i = 0; i < font->n_faces; ++i) {
269 FT_Face face = font->faces[i];
270 if (FT_Get_Char_Index(face, ch)) {
271 *asc = face->size->metrics.ascender;
272 *desc = -face->size->metrics.descender;
281 * Strike a glyph with a horizontal line; it's possible to underline it
282 * and/or strike through it. For the line's position and size, truetype
283 * tables are consulted. Obviously this relies on the data in the tables
287 static int ass_strike_outline_glyph(FT_Face face, ass_font_t *font,
288 FT_Glyph glyph, int under, int through)
290 TT_OS2 *os2 = FT_Get_Sfnt_Table(face, ft_sfnt_os2);
291 TT_Postscript *ps = FT_Get_Sfnt_Table(face, ft_sfnt_post);
292 FT_Outline *ol = &((FT_OutlineGlyph) glyph)->outline;
293 int bear, advance, y_scale, i;
296 i = (under ? 4 : 0) + (through ? 4 : 0);
297 ol->points = realloc(ol->points, sizeof(FT_Vector) *
299 ol->tags = realloc(ol->tags, ol->n_points + i);
300 i = !!under + !!through;
301 ol->contours = realloc(ol->contours, sizeof(short) *
302 (ol->n_contours + i));
304 // If the bearing is negative, the glyph starts left of the current
306 bear = FFMIN(face->glyph->metrics.horiBearingX, 0);
307 // We're adding half a pixel to avoid small gaps
308 advance = d16_to_d6(glyph->advance.x) + 32;
309 y_scale = face->size->metrics.y_scale;
311 // Add points to the outline
314 pos = FT_MulFix(ps->underlinePosition, y_scale * font->scale_y);
315 size = FT_MulFix(ps->underlineThickness,
316 y_scale * font->scale_y / 2);
318 if (pos > 0 || size <= 0)
321 FT_Vector points[4] = {
322 {.x = bear, .y = pos + size},
323 {.x = advance, .y = pos + size},
324 {.x = advance, .y = pos - size},
325 {.x = bear, .y = pos - size},
328 for (i = 0; i < 4; i++) {
329 ol->points[ol->n_points] = points[i];
330 ol->tags[ol->n_points++] = 1;
332 ol->contours[ol->n_contours++] = ol->n_points - 1;
337 pos = FT_MulFix(os2->yStrikeoutPosition, y_scale * font->scale_y);
338 size = FT_MulFix(os2->yStrikeoutSize, y_scale * font->scale_y / 2);
340 if (pos < 0 || size <= 0)
343 FT_Vector points[4] = {
344 {.x = bear, .y = pos + size},
345 {.x = advance, .y = pos + size},
346 {.x = advance, .y = pos - size},
347 {.x = bear, .y = pos - size},
350 for (i = 0; i < 4; i++) {
351 ol->points[ol->n_points] = points[i];
352 ol->tags[ol->n_points++] = 1;
355 ol->contours[ol->n_contours++] = ol->n_points - 1;
363 * \param ch character code
365 FT_Glyph ass_font_get_glyph(void *fontconfig_priv, ass_font_t *font,
366 uint32_t ch, ass_hinting_t hinting, int deco)
377 if (font->n_faces == 0)
380 for (i = 0; i < font->n_faces; ++i) {
381 face = font->faces[i];
382 index = FT_Get_Char_Index(face, ch);
387 #ifdef CONFIG_FONTCONFIG
390 ass_msg(font->library, MSGL_INFO,
391 "Glyph 0x%X not found, selecting one more "
392 "font for (%s, %d, %d)", ch, font->desc.family,
393 font->desc.bold, font->desc.italic);
394 face_idx = add_face(fontconfig_priv, font, ch);
396 face = font->faces[face_idx];
397 index = FT_Get_Char_Index(face, ch);
399 ass_msg(font->library, MSGL_ERR,
400 "Glyph 0x%X not found in font for (%s, %d, %d)",
401 ch, font->desc.family, font->desc.bold,
409 case ASS_HINTING_NONE:
410 flags = FT_LOAD_NO_HINTING;
412 case ASS_HINTING_LIGHT:
413 flags = FT_LOAD_FORCE_AUTOHINT | FT_LOAD_TARGET_LIGHT;
415 case ASS_HINTING_NORMAL:
416 flags = FT_LOAD_FORCE_AUTOHINT;
418 case ASS_HINTING_NATIVE:
423 error = FT_Load_Glyph(face, index, FT_LOAD_NO_BITMAP | flags);
425 ass_msg(font->library, MSGL_WARN, "Error loading glyph, index %d",
429 #if (FREETYPE_MAJOR > 2) || \
430 ((FREETYPE_MAJOR == 2) && (FREETYPE_MINOR >= 2)) || \
431 ((FREETYPE_MAJOR == 2) && (FREETYPE_MINOR == 1) && (FREETYPE_PATCH >= 10))
432 // FreeType >= 2.1.10 required
433 if (!(face->style_flags & FT_STYLE_FLAG_ITALIC) &&
434 (font->desc.italic > 55)) {
435 FT_GlyphSlot_Oblique(face->glyph);
438 error = FT_Get_Glyph(face->glyph, &glyph);
440 ass_msg(font->library, MSGL_WARN, "Error loading glyph, index %d",
445 ass_strike_outline_glyph(face, font, glyph, deco & DECO_UNDERLINE,
446 deco & DECO_STRIKETHROUGH);
452 * \brief Get kerning for the pair of glyphs.
454 FT_Vector ass_font_get_kerning(ass_font_t *font, uint32_t c1, uint32_t c2)
456 FT_Vector v = { 0, 0 };
459 for (i = 0; i < font->n_faces; ++i) {
460 FT_Face face = font->faces[i];
461 int i1 = FT_Get_Char_Index(face, c1);
462 int i2 = FT_Get_Char_Index(face, c2);
464 if (FT_HAS_KERNING(face))
465 FT_Get_Kerning(face, i1, i2, FT_KERNING_DEFAULT, &v);
468 if (i1 || i2) // these glyphs are from different font faces, no kerning information
475 * \brief Deallocate ass_font_t
477 void ass_font_free(ass_font_t *font)
480 for (i = 0; i < font->n_faces; ++i)
482 FT_Done_Face(font->faces[i]);
483 if (font->desc.family)
484 free(font->desc.family);