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| -rw-r--r-- | gfx/harfbuzz/src/hb-ft.cc | 1042 |
1 files changed, 1042 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/hb-ft.cc b/gfx/harfbuzz/src/hb-ft.cc new file mode 100644 index 0000000000..ab7d6146ce --- /dev/null +++ b/gfx/harfbuzz/src/hb-ft.cc @@ -0,0 +1,1042 @@ +/* + * Copyright © 2009 Red Hat, Inc. + * Copyright © 2009 Keith Stribley + * Copyright © 2015 Google, Inc. + * + * This is part of HarfBuzz, a text shaping library. + * + * Permission is hereby granted, without written agreement and without + * license or royalty fees, to use, copy, modify, and distribute this + * software and its documentation for any purpose, provided that the + * above copyright notice and the following two paragraphs appear in + * all copies of this software. + * + * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR + * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES + * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN + * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, + * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS + * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO + * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. + * + * Red Hat Author(s): Behdad Esfahbod + * Google Author(s): Behdad Esfahbod + */ + +#include "hb.hh" + +#ifdef HAVE_FREETYPE + +#include "hb-ft.h" + +#include "hb-font.hh" +#include "hb-machinery.hh" +#include "hb-cache.hh" + +#include FT_ADVANCES_H +#include FT_MULTIPLE_MASTERS_H +#include FT_TRUETYPE_TABLES_H + + +/** + * SECTION:hb-ft + * @title: hb-ft + * @short_description: FreeType integration + * @include: hb-ft.h + * + * Functions for using HarfBuzz with the FreeType library. + * + * HarfBuzz supports using FreeType to provide face and + * font data. + * + * <note>Note that FreeType is not thread-safe, therefore these + * functions are not thread-safe either.</note> + **/ + + +/* TODO: + * + * In general, this file does a fine job of what it's supposed to do. + * There are, however, things that need more work: + * + * - FreeType works in 26.6 mode. Clients can decide to use that mode, and everything + * would work fine. However, we also abuse this API for performing in font-space, + * but don't pass the correct flags to FreeType. We just abuse the no-hinting mode + * for that, such that no rounding etc happens. As such, we don't set ppem, and + * pass NO_HINTING as load_flags. Would be much better to use NO_SCALE, and scale + * ourselves. + * + * - We don't handle / allow for emboldening / obliqueing. + * + * - In the future, we should add constructors to create fonts in font space? + */ + + +struct hb_ft_font_t +{ + mutable hb_mutex_t lock; + FT_Face ft_face; + int load_flags; + bool symbol; /* Whether selected cmap is symbol cmap. */ + bool unref; /* Whether to destroy ft_face when done. */ + + mutable hb_atomic_int_t cached_x_scale; + mutable hb_advance_cache_t advance_cache; +}; + +static hb_ft_font_t * +_hb_ft_font_create (FT_Face ft_face, bool symbol, bool unref) +{ + hb_ft_font_t *ft_font = (hb_ft_font_t *) calloc (1, sizeof (hb_ft_font_t)); + if (unlikely (!ft_font)) return nullptr; + + ft_font->lock.init (); + ft_font->ft_face = ft_face; + ft_font->symbol = symbol; + ft_font->unref = unref; + + ft_font->load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING; + + ft_font->cached_x_scale.set_relaxed (0); + ft_font->advance_cache.init (); + + return ft_font; +} + +static void +_hb_ft_face_destroy (void *data) +{ + FT_Done_Face ((FT_Face) data); +} + +static void +_hb_ft_font_destroy (void *data) +{ + hb_ft_font_t *ft_font = (hb_ft_font_t *) data; + + ft_font->advance_cache.fini (); + + if (ft_font->unref) + _hb_ft_face_destroy (ft_font->ft_face); + + ft_font->lock.fini (); + + free (ft_font); +} + +/** + * hb_ft_font_set_load_flags: + * @font: #hb_font_t to work upon + * @load_flags: The FreeType load flags to set + * + * Sets the FT_Load_Glyph load flags for the specified #hb_font_t. + * + * For more information, see + * https://www.freetype.org/freetype2/docs/reference/ft2-base_interface.html#ft_load_xxx + * + * Since: 1.0.5 + **/ +void +hb_ft_font_set_load_flags (hb_font_t *font, int load_flags) +{ + if (hb_object_is_immutable (font)) + return; + + if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)) + return; + + hb_ft_font_t *ft_font = (hb_ft_font_t *) font->user_data; + + ft_font->load_flags = load_flags; +} + +/** + * hb_ft_font_get_load_flags: + * @font: #hb_font_t to work upon + * + * Fetches the FT_Load_Glyph load flags of the specified #hb_font_t. + * + * For more information, see + * https://www.freetype.org/freetype2/docs/reference/ft2-base_interface.html#ft_load_xxx + * + * Return value: FT_Load_Glyph flags found + * + * Since: 1.0.5 + **/ +int +hb_ft_font_get_load_flags (hb_font_t *font) +{ + if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)) + return 0; + + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data; + + return ft_font->load_flags; +} + +/** + * hb_ft_get_face: + * @font: #hb_font_t to work upon + * + * Fetches the FT_Face associated with the specified #hb_font_t + * font object. + * + * Return value: the FT_Face found + * + * Since: 0.9.2 + **/ +FT_Face +hb_ft_font_get_face (hb_font_t *font) +{ + if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)) + return nullptr; + + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data; + + return ft_font->ft_face; +} + +/** + * hb_ft_font_lock_face: + * @font: + * + * + * + * Return value: + * Since: 2.6.5 + **/ +FT_Face +hb_ft_font_lock_face (hb_font_t *font) +{ + if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)) + return nullptr; + + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data; + + ft_font->lock.lock (); + + return ft_font->ft_face; +} + +/** + * hb_ft_font_unlock_face: + * @font: + * + * + * + * Return value: + * Since: 2.6.5 + **/ +void +hb_ft_font_unlock_face (hb_font_t *font) +{ + if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)) + return; + + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data; + + ft_font->lock.unlock (); +} + + +static hb_bool_t +hb_ft_get_nominal_glyph (hb_font_t *font HB_UNUSED, + void *font_data, + hb_codepoint_t unicode, + hb_codepoint_t *glyph, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + unsigned int g = FT_Get_Char_Index (ft_font->ft_face, unicode); + + if (unlikely (!g)) + { + if (unlikely (ft_font->symbol) && unicode <= 0x00FFu) + { + /* For symbol-encoded OpenType fonts, we duplicate the + * U+F000..F0FF range at U+0000..U+00FF. That's what + * Windows seems to do, and that's hinted about at: + * https://docs.microsoft.com/en-us/typography/opentype/spec/recom + * under "Non-Standard (Symbol) Fonts". */ + g = FT_Get_Char_Index (ft_font->ft_face, 0xF000u + unicode); + if (!g) + return false; + } + else + return false; + } + + *glyph = g; + return true; +} + +static unsigned int +hb_ft_get_nominal_glyphs (hb_font_t *font HB_UNUSED, + void *font_data, + unsigned int count, + const hb_codepoint_t *first_unicode, + unsigned int unicode_stride, + hb_codepoint_t *first_glyph, + unsigned int glyph_stride, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + unsigned int done; + for (done = 0; + done < count && (*first_glyph = FT_Get_Char_Index (ft_font->ft_face, *first_unicode)); + done++) + { + first_unicode = &StructAtOffsetUnaligned<hb_codepoint_t> (first_unicode, unicode_stride); + first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride); + } + /* We don't need to do ft_font->symbol dance here, since HB calls the singular + * nominal_glyph() for what we don't handle here. */ + return done; +} + + +static hb_bool_t +hb_ft_get_variation_glyph (hb_font_t *font HB_UNUSED, + void *font_data, + hb_codepoint_t unicode, + hb_codepoint_t variation_selector, + hb_codepoint_t *glyph, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + unsigned int g = FT_Face_GetCharVariantIndex (ft_font->ft_face, unicode, variation_selector); + + if (unlikely (!g)) + return false; + + *glyph = g; + return true; +} + +static void +hb_ft_get_glyph_h_advances (hb_font_t* font, void* font_data, + unsigned count, + const hb_codepoint_t *first_glyph, + unsigned glyph_stride, + hb_position_t *first_advance, + unsigned advance_stride, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + FT_Face ft_face = ft_font->ft_face; + int load_flags = ft_font->load_flags; + int mult = font->x_scale < 0 ? -1 : +1; + + if (font->x_scale != ft_font->cached_x_scale.get ()) + { + ft_font->advance_cache.clear (); + ft_font->cached_x_scale.set (font->x_scale); + } + + for (unsigned int i = 0; i < count; i++) + { + FT_Fixed v = 0; + hb_codepoint_t glyph = *first_glyph; + + unsigned int cv; + if (ft_font->advance_cache.get (glyph, &cv)) + v = cv; + else + { + FT_Get_Advance (ft_face, glyph, load_flags, &v); + ft_font->advance_cache.set (glyph, v); + } + + *first_advance = (v * mult + (1<<9)) >> 10; + first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride); + first_advance = &StructAtOffsetUnaligned<hb_position_t> (first_advance, advance_stride); + } +} + +static hb_position_t +hb_ft_get_glyph_v_advance (hb_font_t *font, + void *font_data, + hb_codepoint_t glyph, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + FT_Fixed v; + + if (unlikely (FT_Get_Advance (ft_font->ft_face, glyph, ft_font->load_flags | FT_LOAD_VERTICAL_LAYOUT, &v))) + return 0; + + if (font->y_scale < 0) + v = -v; + + /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates + * have a Y growing upward. Hence the extra negation. */ + return (-v + (1<<9)) >> 10; +} + +static hb_bool_t +hb_ft_get_glyph_v_origin (hb_font_t *font, + void *font_data, + hb_codepoint_t glyph, + hb_position_t *x, + hb_position_t *y, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + FT_Face ft_face = ft_font->ft_face; + + if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags))) + return false; + + /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates + * have a Y growing upward. Hence the extra negation. */ + *x = ft_face->glyph->metrics.horiBearingX - ft_face->glyph->metrics.vertBearingX; + *y = ft_face->glyph->metrics.horiBearingY - (-ft_face->glyph->metrics.vertBearingY); + + if (font->x_scale < 0) + *x = -*x; + if (font->y_scale < 0) + *y = -*y; + + return true; +} + +#ifndef HB_NO_OT_SHAPE_FALLBACK +static hb_position_t +hb_ft_get_glyph_h_kerning (hb_font_t *font, + void *font_data, + hb_codepoint_t left_glyph, + hb_codepoint_t right_glyph, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + FT_Vector kerningv; + + FT_Kerning_Mode mode = font->x_ppem ? FT_KERNING_DEFAULT : FT_KERNING_UNFITTED; + if (FT_Get_Kerning (ft_font->ft_face, left_glyph, right_glyph, mode, &kerningv)) + return 0; + + return kerningv.x; +} +#endif + +static hb_bool_t +hb_ft_get_glyph_extents (hb_font_t *font, + void *font_data, + hb_codepoint_t glyph, + hb_glyph_extents_t *extents, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + FT_Face ft_face = ft_font->ft_face; + + if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags))) + return false; + + extents->x_bearing = ft_face->glyph->metrics.horiBearingX; + extents->y_bearing = ft_face->glyph->metrics.horiBearingY; + extents->width = ft_face->glyph->metrics.width; + extents->height = -ft_face->glyph->metrics.height; + if (font->x_scale < 0) + { + extents->x_bearing = -extents->x_bearing; + extents->width = -extents->width; + } + if (font->y_scale < 0) + { + extents->y_bearing = -extents->y_bearing; + extents->height = -extents->height; + } + return true; +} + +static hb_bool_t +hb_ft_get_glyph_contour_point (hb_font_t *font HB_UNUSED, + void *font_data, + hb_codepoint_t glyph, + unsigned int point_index, + hb_position_t *x, + hb_position_t *y, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + FT_Face ft_face = ft_font->ft_face; + + if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags))) + return false; + + if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE)) + return false; + + if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points)) + return false; + + *x = ft_face->glyph->outline.points[point_index].x; + *y = ft_face->glyph->outline.points[point_index].y; + + return true; +} + +static hb_bool_t +hb_ft_get_glyph_name (hb_font_t *font HB_UNUSED, + void *font_data, + hb_codepoint_t glyph, + char *name, unsigned int size, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + FT_Face ft_face = ft_font->ft_face; + + hb_bool_t ret = !FT_Get_Glyph_Name (ft_face, glyph, name, size); + if (ret && (size && !*name)) + ret = false; + + return ret; +} + +static hb_bool_t +hb_ft_get_glyph_from_name (hb_font_t *font HB_UNUSED, + void *font_data, + const char *name, int len, /* -1 means nul-terminated */ + hb_codepoint_t *glyph, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + FT_Face ft_face = ft_font->ft_face; + + if (len < 0) + *glyph = FT_Get_Name_Index (ft_face, (FT_String *) name); + else { + /* Make a nul-terminated version. */ + char buf[128]; + len = hb_min (len, (int) sizeof (buf) - 1); + strncpy (buf, name, len); + buf[len] = '\0'; + *glyph = FT_Get_Name_Index (ft_face, buf); + } + + if (*glyph == 0) + { + /* Check whether the given name was actually the name of glyph 0. */ + char buf[128]; + if (!FT_Get_Glyph_Name(ft_face, 0, buf, sizeof (buf)) && + len < 0 ? !strcmp (buf, name) : !strncmp (buf, name, len)) + return true; + } + + return *glyph != 0; +} + +static hb_bool_t +hb_ft_get_font_h_extents (hb_font_t *font HB_UNUSED, + void *font_data, + hb_font_extents_t *metrics, + void *user_data HB_UNUSED) +{ + const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data; + hb_lock_t lock (ft_font->lock); + FT_Face ft_face = ft_font->ft_face; + metrics->ascender = FT_MulFix(ft_face->ascender, ft_face->size->metrics.y_scale); + metrics->descender = FT_MulFix(ft_face->descender, ft_face->size->metrics.y_scale); + metrics->line_gap = FT_MulFix( ft_face->height, ft_face->size->metrics.y_scale ) - (metrics->ascender - metrics->descender); + if (font->y_scale < 0) + { + metrics->ascender = -metrics->ascender; + metrics->descender = -metrics->descender; + metrics->line_gap = -metrics->line_gap; + } + return true; +} + +#if HB_USE_ATEXIT +static void free_static_ft_funcs (); +#endif + +static struct hb_ft_font_funcs_lazy_loader_t : hb_font_funcs_lazy_loader_t<hb_ft_font_funcs_lazy_loader_t> +{ + static hb_font_funcs_t *create () + { + hb_font_funcs_t *funcs = hb_font_funcs_create (); + + hb_font_funcs_set_font_h_extents_func (funcs, hb_ft_get_font_h_extents, nullptr, nullptr); + //hb_font_funcs_set_font_v_extents_func (funcs, hb_ft_get_font_v_extents, nullptr, nullptr); + hb_font_funcs_set_nominal_glyph_func (funcs, hb_ft_get_nominal_glyph, nullptr, nullptr); + hb_font_funcs_set_nominal_glyphs_func (funcs, hb_ft_get_nominal_glyphs, nullptr, nullptr); + hb_font_funcs_set_variation_glyph_func (funcs, hb_ft_get_variation_glyph, nullptr, nullptr); + hb_font_funcs_set_glyph_h_advances_func (funcs, hb_ft_get_glyph_h_advances, nullptr, nullptr); + hb_font_funcs_set_glyph_v_advance_func (funcs, hb_ft_get_glyph_v_advance, nullptr, nullptr); + //hb_font_funcs_set_glyph_h_origin_func (funcs, hb_ft_get_glyph_h_origin, nullptr, nullptr); + hb_font_funcs_set_glyph_v_origin_func (funcs, hb_ft_get_glyph_v_origin, nullptr, nullptr); +#ifndef HB_NO_OT_SHAPE_FALLBACK + hb_font_funcs_set_glyph_h_kerning_func (funcs, hb_ft_get_glyph_h_kerning, nullptr, nullptr); +#endif + //hb_font_funcs_set_glyph_v_kerning_func (funcs, hb_ft_get_glyph_v_kerning, nullptr, nullptr); + hb_font_funcs_set_glyph_extents_func (funcs, hb_ft_get_glyph_extents, nullptr, nullptr); + hb_font_funcs_set_glyph_contour_point_func (funcs, hb_ft_get_glyph_contour_point, nullptr, nullptr); + hb_font_funcs_set_glyph_name_func (funcs, hb_ft_get_glyph_name, nullptr, nullptr); + hb_font_funcs_set_glyph_from_name_func (funcs, hb_ft_get_glyph_from_name, nullptr, nullptr); + + hb_font_funcs_make_immutable (funcs); + +#if HB_USE_ATEXIT + atexit (free_static_ft_funcs); +#endif + + return funcs; + } +} static_ft_funcs; + +#if HB_USE_ATEXIT +static +void free_static_ft_funcs () +{ + static_ft_funcs.free_instance (); +} +#endif + +static hb_font_funcs_t * +_hb_ft_get_font_funcs () +{ + return static_ft_funcs.get_unconst (); +} + +static void +_hb_ft_font_set_funcs (hb_font_t *font, FT_Face ft_face, bool unref) +{ + bool symbol = ft_face->charmap && ft_face->charmap->encoding == FT_ENCODING_MS_SYMBOL; + + hb_ft_font_t *ft_font = _hb_ft_font_create (ft_face, symbol, unref); + if (unlikely (!ft_font)) return; + + hb_font_set_funcs (font, + _hb_ft_get_font_funcs (), + ft_font, + _hb_ft_font_destroy); +} + + +static hb_blob_t * +_hb_ft_reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data) +{ + FT_Face ft_face = (FT_Face) user_data; + FT_Byte *buffer; + FT_ULong length = 0; + FT_Error error; + + /* Note: FreeType like HarfBuzz uses the NONE tag for fetching the entire blob */ + + error = FT_Load_Sfnt_Table (ft_face, tag, 0, nullptr, &length); + if (error) + return nullptr; + + buffer = (FT_Byte *) malloc (length); + if (!buffer) + return nullptr; + + error = FT_Load_Sfnt_Table (ft_face, tag, 0, buffer, &length); + if (error) + { + free (buffer); + return nullptr; + } + + return hb_blob_create ((const char *) buffer, length, + HB_MEMORY_MODE_WRITABLE, + buffer, free); +} + +/** + * hb_ft_face_create: + * @ft_face: (destroy destroy) (scope notified): FT_Face to work upon + * @destroy: (optional): A callback to call when the face object is not needed anymore + * + * Creates an #hb_face_t face object from the specified FT_Face. + * + * This variant of the function does not provide any life-cycle management. + * + * Most client programs should use hb_ft_face_create_referenced() + * (or, perhaps, hb_ft_face_create_cached()) instead. + * + * If you know you have valid reasons not to use hb_ft_face_create_referenced(), + * then it is the client program's responsibility to destroy @ft_face + * after the #hb_face_t face object has been destroyed. + * + * Return value: (transfer full): the new #hb_face_t face object + * + * Since: 0.9.2 + **/ +hb_face_t * +hb_ft_face_create (FT_Face ft_face, + hb_destroy_func_t destroy) +{ + hb_face_t *face; + + if (!ft_face->stream->read) { + hb_blob_t *blob; + + blob = hb_blob_create ((const char *) ft_face->stream->base, + (unsigned int) ft_face->stream->size, + HB_MEMORY_MODE_READONLY, + ft_face, destroy); + face = hb_face_create (blob, ft_face->face_index); + hb_blob_destroy (blob); + } else { + face = hb_face_create_for_tables (_hb_ft_reference_table, ft_face, destroy); + } + + hb_face_set_index (face, ft_face->face_index); + hb_face_set_upem (face, ft_face->units_per_EM); + + return face; +} + +/** + * hb_ft_face_create_referenced: + * @ft_face: FT_Face to work upon + * + * Creates an #hb_face_t face object from the specified FT_Face. + * + * This is the preferred variant of the hb_ft_face_create* + * function family, because it calls FT_Reference_Face() on @ft_face, + * ensuring that @ft_face remains alive as long as the resulting + * #hb_face_t face object remains alive. Also calls FT_Done_Face() + * when the #hb_face_t face object is destroyed. + * + * Use this version unless you know you have good reasons not to. + * + * Return value: (transfer full): the new #hb_face_t face object + * + * Since: 0.9.38 + **/ +hb_face_t * +hb_ft_face_create_referenced (FT_Face ft_face) +{ + FT_Reference_Face (ft_face); + return hb_ft_face_create (ft_face, _hb_ft_face_destroy); +} + +static void +hb_ft_face_finalize (FT_Face ft_face) +{ + hb_face_destroy ((hb_face_t *) ft_face->generic.data); +} + +/** + * hb_ft_face_create_cached: + * @ft_face: FT_Face to work upon + * + * Creates an #hb_face_t face object from the specified FT_Face. + * + * This variant of the function caches the newly created #hb_face_t + * face object, using the @generic pointer of @ft_face. Subsequent function + * calls that are passed the same @ft_face parameter will have the same + * #hb_face_t returned to them, and that #hb_face_t will be correctly + * reference counted. + * + * However, client programs are still responsible for destroying + * @ft_face after the last #hb_face_t face object has been destroyed. + * + * Return value: (transfer full): the new #hb_face_t face object + * + * Since: 0.9.2 + **/ +hb_face_t * +hb_ft_face_create_cached (FT_Face ft_face) +{ + if (unlikely (!ft_face->generic.data || ft_face->generic.finalizer != (FT_Generic_Finalizer) hb_ft_face_finalize)) + { + if (ft_face->generic.finalizer) + ft_face->generic.finalizer (ft_face); + + ft_face->generic.data = hb_ft_face_create (ft_face, nullptr); + ft_face->generic.finalizer = (FT_Generic_Finalizer) hb_ft_face_finalize; + } + + return hb_face_reference ((hb_face_t *) ft_face->generic.data); +} + +/** + * hb_ft_font_create: + * @ft_face: (destroy destroy) (scope notified): FT_Face to work upon + * @destroy: (optional): A callback to call when the font object is not needed anymore + * + * Creates an #hb_font_t font object from the specified FT_Face. + * + * <note>Note: You must set the face size on @ft_face before calling + * hb_ft_font_create() on it. Otherwise, HarfBuzz will not pick up + * the face size.</note> + * + * This variant of the function does not provide any life-cycle management. + * + * Most client programs should use hb_ft_font_create_referenced() + * instead. + * + * If you know you have valid reasons not to use hb_ft_font_create_referenced(), + * then it is the client program's responsibility to destroy @ft_face + * after the #hb_font_t font object has been destroyed. + * + * HarfBuzz will use the @destroy callback on the #hb_font_t font object + * if it is supplied when you use this function. However, even if @destroy + * is provided, it is the client program's responsibility to destroy @ft_face, + * and it is the client program's responsibility to ensure that @ft_face is + * destroyed only after the #hb_font_t font object has been destroyed. + * + * Return value: (transfer full): the new #hb_font_t font object + * + * Since: 0.9.2 + **/ +hb_font_t * +hb_ft_font_create (FT_Face ft_face, + hb_destroy_func_t destroy) +{ + hb_font_t *font; + hb_face_t *face; + + face = hb_ft_face_create (ft_face, destroy); + font = hb_font_create (face); + hb_face_destroy (face); + _hb_ft_font_set_funcs (font, ft_face, false); + hb_ft_font_changed (font); + return font; +} + +/** + * hb_ft_font_has_changed: + * @font: #hb_font_t to work upon + * + * Refreshes the state of @font when the underlying FT_Face has changed. + * This function should be called after changing the size or + * variation-axis settings on the FT_Face. + * + * Since: 1.0.5 + **/ +void +hb_ft_font_changed (hb_font_t *font) +{ + if (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy) + return; + + hb_ft_font_t *ft_font = (hb_ft_font_t *) font->user_data; + + FT_Face ft_face = ft_font->ft_face; + + hb_font_set_scale (font, + (int) (((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM + (1u<<15)) >> 16), + (int) (((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM + (1u<<15)) >> 16)); +#if 0 /* hb-ft works in no-hinting model */ + hb_font_set_ppem (font, + ft_face->size->metrics.x_ppem, + ft_face->size->metrics.y_ppem); +#endif + +#if defined(HAVE_FT_GET_VAR_BLEND_COORDINATES) && !defined(HB_NO_VAR) + FT_MM_Var *mm_var = nullptr; + if (!FT_Get_MM_Var (ft_face, &mm_var)) + { + FT_Fixed *ft_coords = (FT_Fixed *) calloc (mm_var->num_axis, sizeof (FT_Fixed)); + int *coords = (int *) calloc (mm_var->num_axis, sizeof (int)); + if (coords && ft_coords) + { + if (!FT_Get_Var_Blend_Coordinates (ft_face, mm_var->num_axis, ft_coords)) + { + bool nonzero = false; + + for (unsigned int i = 0; i < mm_var->num_axis; ++i) + { + coords[i] = ft_coords[i] >>= 2; + nonzero = nonzero || coords[i]; + } + + if (nonzero) + hb_font_set_var_coords_normalized (font, coords, mm_var->num_axis); + else + hb_font_set_var_coords_normalized (font, nullptr, 0); + } + } + free (coords); + free (ft_coords); +#ifdef HAVE_FT_DONE_MM_VAR + FT_Done_MM_Var (ft_face->glyph->library, mm_var); +#else + free (mm_var); +#endif + } +#endif +} + +/** + * hb_ft_font_create_referenced: + * @ft_face: FT_Face to work upon + * + * Creates an #hb_font_t font object from the specified FT_Face. + * + * <note>Note: You must set the face size on @ft_face before calling + * hb_ft_font_create_references() on it. Otherwise, HarfBuzz will not pick up + * the face size.</note> + * + * This is the preferred variant of the hb_ft_font_create* + * function family, because it calls FT_Reference_Face() on @ft_face, + * ensuring that @ft_face remains alive as long as the resulting + * #hb_font_t font object remains alive. + * + * Use this version unless you know you have good reasons not to. + * + * Return value: (transfer full): the new #hb_font_t font object + * + * Since: 0.9.38 + **/ +hb_font_t * +hb_ft_font_create_referenced (FT_Face ft_face) +{ + FT_Reference_Face (ft_face); + return hb_ft_font_create (ft_face, _hb_ft_face_destroy); +} + +#if HB_USE_ATEXIT +static void free_static_ft_library (); +#endif + +static struct hb_ft_library_lazy_loader_t : hb_lazy_loader_t<hb_remove_pointer<FT_Library>, + hb_ft_library_lazy_loader_t> +{ + static FT_Library create () + { + FT_Library l; + if (FT_Init_FreeType (&l)) + return nullptr; + +#if HB_USE_ATEXIT + atexit (free_static_ft_library); +#endif + + return l; + } + static void destroy (FT_Library l) + { + FT_Done_FreeType (l); + } + static FT_Library get_null () + { + return nullptr; + } +} static_ft_library; + +#if HB_USE_ATEXIT +static +void free_static_ft_library () +{ + static_ft_library.free_instance (); +} +#endif + +static FT_Library +get_ft_library () +{ + return static_ft_library.get_unconst (); +} + +static void +_release_blob (FT_Face ft_face) +{ + hb_blob_destroy ((hb_blob_t *) ft_face->generic.data); +} + +/** + * hb_ft_font_set_funcs: + * @font: #hb_font_t to work upon + * + * Configures the font-functions structure of the specified + * #hb_font_t font object to use FreeType font functions. + * + * In particular, you can use this function to configure an + * existing #hb_face_t face object for use with FreeType font + * functions even if that #hb_face_t face object was initially + * created with hb_face_create(), and therefore was not + * initially configured to use FreeType font functions. + * + * An #hb_face_t face object created with hb_ft_face_create() + * is preconfigured for FreeType font functions and does not + * require this function to be used. + * + * <note>Note: Internally, this function creates an FT_Face. +* </note> + * + * Since: 1.0.5 + **/ +void +hb_ft_font_set_funcs (hb_font_t *font) +{ + hb_blob_t *blob = hb_face_reference_blob (font->face); + unsigned int blob_length; + const char *blob_data = hb_blob_get_data (blob, &blob_length); + if (unlikely (!blob_length)) + DEBUG_MSG (FT, font, "Font face has empty blob"); + + FT_Face ft_face = nullptr; + FT_Error err = FT_New_Memory_Face (get_ft_library (), + (const FT_Byte *) blob_data, + blob_length, + hb_face_get_index (font->face), + &ft_face); + + if (unlikely (err)) { + hb_blob_destroy (blob); + DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed"); + return; + } + + if (FT_Select_Charmap (ft_face, FT_ENCODING_MS_SYMBOL)) + FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE); + + FT_Set_Char_Size (ft_face, + abs (font->x_scale), abs (font->y_scale), + 0, 0); +#if 0 + font->x_ppem * 72 * 64 / font->x_scale, + font->y_ppem * 72 * 64 / font->y_scale); +#endif + if (font->x_scale < 0 || font->y_scale < 0) + { + FT_Matrix matrix = { font->x_scale < 0 ? -1 : +1, 0, + 0, font->y_scale < 0 ? -1 : +1}; + FT_Set_Transform (ft_face, &matrix, nullptr); + } + +#if defined(HAVE_FT_GET_VAR_BLEND_COORDINATES) && !defined(HB_NO_VAR) + unsigned int num_coords; + const int *coords = hb_font_get_var_coords_normalized (font, &num_coords); + if (num_coords) + { + FT_Fixed *ft_coords = (FT_Fixed *) calloc (num_coords, sizeof (FT_Fixed)); + if (ft_coords) + { + for (unsigned int i = 0; i < num_coords; i++) + ft_coords[i] = coords[i] * 4; + FT_Set_Var_Blend_Coordinates (ft_face, num_coords, ft_coords); + free (ft_coords); + } + } +#endif + + ft_face->generic.data = blob; + ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob; + + _hb_ft_font_set_funcs (font, ft_face, true); + hb_ft_font_set_load_flags (font, FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING); +} + + +#endif |