Aegisub/libass/ass_font.c

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// -*- c-basic-offset: 8; indent-tabs-mode: t -*-
// vim:ts=8:sw=8:noet:ai:
/*
Copyright (C) 2006 Evgeniy Stepanov <eugeni.stepanov@gmail.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include <inttypes.h>
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_SYNTHESIS_H
#include FT_GLYPH_H
#include "ass.h"
#include "ass_library.h"
#include "ass_font.h"
#include "ass_bitmap.h"
#include "ass_cache.h"
#include "ass_fontconfig.h"
#include "mputils.h"
/**
* Select Microfost Unicode CharMap, if the font has one.
* Otherwise, let FreeType decide.
*/
static void charmap_magic(FT_Face face)
{
int i;
for (i = 0; i < face->num_charmaps; ++i) {
FT_CharMap cmap = face->charmaps[i];
unsigned pid = cmap->platform_id;
unsigned eid = cmap->encoding_id;
if (pid == 3 /*microsoft*/ && (eid == 1 /*unicode bmp*/ || eid == 10 /*full unicode*/)) {
FT_Set_Charmap(face, cmap);
return;
}
}
if (!face->charmap) {
if (face->num_charmaps == 0) {
mp_msg(MSGT_ASS, MSGL_WARN, MSGTR_LIBASS_NoCharmaps);
return;
}
mp_msg(MSGT_ASS, MSGL_WARN, MSGTR_LIBASS_NoCharmapAutodetected);
FT_Set_Charmap(face, face->charmaps[0]);
return;
}
}
/**
* \brief find a memory font by name
*/
static int find_font(ass_library_t* library, char* name)
{
int i;
for (i = 0; i < library->num_fontdata; ++i)
if (strcasecmp(name, library->fontdata[i].name) == 0)
return i;
return -1;
}
/**
* \brief Create a new ass_font_t according to "desc" argument
*/
ass_font_t* ass_font_new(ass_library_t* library, FT_Library ftlibrary, void* fc_priv, ass_font_desc_t* desc)
{
char* path;
int index;
FT_Face face;
int error;
ass_font_t* font;
int mem_idx;
font = ass_font_cache_find(desc);
if (font)
return font;
path = fontconfig_select(fc_priv, desc->family, desc->bold, desc->italic, &index);
mem_idx = find_font(library, path);
if (mem_idx >= 0) {
error = FT_New_Memory_Face(ftlibrary, (unsigned char*)library->fontdata[mem_idx].data,
library->fontdata[mem_idx].size, 0, &face);
if (error) {
mp_msg(MSGT_ASS, MSGL_WARN, MSGTR_LIBASS_ErrorOpeningMemoryFont, path);
return 0;
}
} else {
error = FT_New_Face(ftlibrary, path, index, &face);
if (error) {
mp_msg(MSGT_ASS, MSGL_WARN, MSGTR_LIBASS_ErrorOpeningFont, path, index);
return 0;
}
}
charmap_magic(face);
font = calloc(1, sizeof(ass_font_t));
font->ftlibrary = ftlibrary;
font->faces[0] = face;
font->n_faces = 1;
font->desc.family = strdup(desc->family);
font->desc.bold = desc->bold;
font->desc.italic = desc->italic;
font->m.xx = font->m.yy = (FT_Fixed)0x10000L;
font->m.xy = font->m.yy = 0;
font->v.x = font->v.y = 0;
font->size = 0;
#ifdef HAVE_FONTCONFIG
font->charset = FcCharSetCreate();
#endif
ass_font_cache_add(font);
return font;
}
/**
* \brief Set font transformation matrix and shift vector
**/
void ass_font_set_transform(ass_font_t* font, FT_Matrix* m, FT_Vector* v)
{
int i;
font->m.xx = m->xx;
font->m.xy = m->xy;
font->m.yx = m->yx;
font->m.yy = m->yy;
font->v.x = v->x;
font->v.y = v->y;
for (i = 0; i < font->n_faces; ++i)
FT_Set_Transform(font->faces[i], &font->m, &font->v);
}
/**
* \brief Set font size
**/
void ass_font_set_size(ass_font_t* font, int size)
{
int i;
if (font->size != size) {
font->size = size;
for (i = 0; i < font->n_faces; ++i)
FT_Set_Pixel_Sizes(font->faces[i], 0, size);
}
}
#ifdef HAVE_FONTCONFIG
/**
* \brief Select a new FT_Face with the given character
* The new face is added to the end of font->faces.
**/
static void ass_font_reselect(void* fontconfig_priv, ass_font_t* font, uint32_t ch)
{
char* path;
int index;
FT_Face face;
int error;
if (font->n_faces == ASS_FONT_MAX_FACES)
return;
path = fontconfig_select_with_charset(fontconfig_priv, font->desc.family, font->desc.bold,
font->desc.italic, &index, font->charset);
error = FT_New_Face(font->ftlibrary, path, index, &face);
if (error) {
mp_msg(MSGT_ASS, MSGL_WARN, MSGTR_LIBASS_ErrorOpeningFont, path, index);
return;
}
charmap_magic(face);
error = FT_Get_Char_Index(face, ch);
if (error == 0) { // the new font face is not better then the old one
FT_Done_Face(face);
return;
}
font->faces[font->n_faces++] = face;
FT_Set_Transform(face, &font->m, &font->v);
FT_Set_Pixel_Sizes(face, 0, font->size);
}
#endif
/**
* \brief Get maximal font ascender and descender.
* \param ch character code
* The values are extracted from the font face that provides glyphs for the given character
**/
void ass_font_get_asc_desc(ass_font_t* font, uint32_t ch, int* asc, int* desc)
{
int i;
for (i = 0; i < font->n_faces; ++i) {
FT_Face face = font->faces[i];
if (FT_Get_Char_Index(face, ch)) {
int v, v2;
v = face->size->metrics.ascender;
v2 = FT_MulFix(face->bbox.yMax, face->size->metrics.y_scale);
*asc = (v > v2 * 0.9) ? v : v2;
v = - face->size->metrics.descender;
v2 = - FT_MulFix(face->bbox.yMin, face->size->metrics.y_scale);
*desc = (v > v2 * 0.9) ? v : v2;
return;
}
}
*asc = *desc = 0;
}
/**
* \brief Get a glyph
* \param ch character code
**/
FT_Glyph ass_font_get_glyph(void* fontconfig_priv, ass_font_t* font, uint32_t ch)
{
int error;
int index = 0;
int i;
FT_Glyph glyph;
FT_Face face = 0;
if (ch < 0x20)
return 0;
if (font->n_faces == 0)
return 0;
for (i = 0; i < font->n_faces; ++i) {
face = font->faces[i];
index = FT_Get_Char_Index(face, ch);
if (index)
break;
}
#ifdef HAVE_FONTCONFIG
FcCharSetAddChar(font->charset, ch);
if (index == 0) {
mp_msg(MSGT_ASS, MSGL_INFO, MSGTR_LIBASS_GlyphNotFoundReselectingFont,
ch, font->desc.family, font->desc.bold, font->desc.italic);
ass_font_reselect(fontconfig_priv, font, ch);
face = font->faces[font->n_faces - 1];
index = FT_Get_Char_Index(face, ch);
if (index == 0) {
mp_msg(MSGT_ASS, MSGL_ERR, MSGTR_LIBASS_GlyphNotFound,
ch, font->desc.family, font->desc.bold, font->desc.italic);
}
}
#endif
error = FT_Load_Glyph(face, index, FT_LOAD_NO_BITMAP );
if (error) {
mp_msg(MSGT_ASS, MSGL_WARN, MSGTR_LIBASS_ErrorLoadingGlyph);
return 0;
}
#if (FREETYPE_MAJOR > 2) || \
((FREETYPE_MAJOR == 2) && (FREETYPE_MINOR >= 2)) || \
((FREETYPE_MAJOR == 2) && (FREETYPE_MINOR == 1) && (FREETYPE_PATCH >= 10))
// FreeType >= 2.1.10 required
if (!(face->style_flags & FT_STYLE_FLAG_ITALIC) &&
(font->desc.italic > 55)) {
FT_GlyphSlot_Oblique(face->glyph);
}
#endif
error = FT_Get_Glyph(face->glyph, &glyph);
if (error) {
mp_msg(MSGT_ASS, MSGL_WARN, MSGTR_LIBASS_ErrorLoadingGlyph);
return 0;
}
return glyph;
}
/**
* \brief Get kerning for the pair of glyphs.
**/
FT_Vector ass_font_get_kerning(ass_font_t* font, uint32_t c1, uint32_t c2)
{
FT_Vector v = {0, 0};
int i;
for (i = 0; i < font->n_faces; ++i) {
FT_Face face = font->faces[i];
int i1 = FT_Get_Char_Index(face, c1);
int i2 = FT_Get_Char_Index(face, c2);
if (i1 && i2) {
if (FT_HAS_KERNING(face))
FT_Get_Kerning(face, i1, i2, FT_KERNING_DEFAULT, &v);
return v;
}
if (i1 || i2) // these glyphs are from different font faces, no kerning information
return v;
}
return v;
}
/**
* \brief Deallocate ass_font_t
**/
void ass_font_free(ass_font_t* font)
{
int i;
for (i = 0; i < font->n_faces; ++i)
if (font->faces[i]) FT_Done_Face(font->faces[i]);
if (font->desc.family) free(font->desc.family);
#ifdef HAVE_FONTCONFIG
if (font->charset) FcCharSetDestroy(font->charset);
#endif
free(font);
}