/* * Copyright © 2007,2008,2009 Red Hat, Inc. * Copyright © 2012 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 */ #ifndef HB_OT_LAYOUT_PRIVATE_HH #define HB_OT_LAYOUT_PRIVATE_HH #include "hb-private.hh" #include "hb-ot-layout.h" #include "hb-font-private.hh" #include "hb-buffer-private.hh" #include "hb-set-private.hh" /* buffer var allocations, used during the GSUB/GPOS processing */ #define glyph_props() var1.u16[0] /* GDEF glyph properties */ #define syllable() var1.u8[2] /* GSUB/GPOS shaping boundaries */ #define lig_props() var1.u8[3] /* GSUB/GPOS ligature tracking */ #define hb_ot_layout_from_face(face) ((hb_ot_layout_t *) face->shaper_data.ot) /* * GDEF */ typedef enum { HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED = 0x0001, HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH = 0x0002, HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE = 0x0004, HB_OT_LAYOUT_GLYPH_CLASS_MARK = 0x0008, HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT = 0x0010 } hb_ot_layout_glyph_class_t; /* * GSUB/GPOS */ /* lig_id / lig_comp * * When a ligature is formed: * * - The ligature glyph and any marks in between all the same newly allocated * lig_id, * - The ligature glyph will get lig_num_comps set to the number of components * - The marks get lig_comp > 0, reflecting which component of the ligature * they were applied to. * - This is used in GPOS to attach marks to the right component of a ligature * in MarkLigPos. * * When a multiple-substitution is done: * * - All resulting glyphs will have lig_id = 0, * - The resulting glyphs will have lig_comp = 0, 1, 2, ... respectively. * - This is used in GPOS to attach marks to the first component of a * multiple substitution in MarkBasePos. * * The numbers are also used in GPOS to do mark-to-mark positioning only * to marks that belong to the same component of a ligature in MarkMarPos. */ #define IS_LIG_BASE 0x10 static inline void set_lig_props_for_ligature (hb_glyph_info_t &info, unsigned int lig_id, unsigned int lig_num_comps) { info.lig_props() = (lig_id << 5) | IS_LIG_BASE | (lig_num_comps & 0x0F); } static inline void set_lig_props_for_mark (hb_glyph_info_t &info, unsigned int lig_id, unsigned int lig_comp) { info.lig_props() = (lig_id << 5) | (lig_comp & 0x0F); } static inline void set_lig_props_for_component (hb_glyph_info_t &info, unsigned int comp) { set_lig_props_for_mark (info, 0, comp); } static inline unsigned int get_lig_id (const hb_glyph_info_t &info) { return info.lig_props() >> 5; } static inline bool is_a_ligature (const hb_glyph_info_t &info) { return !!(info.lig_props() & IS_LIG_BASE); } static inline unsigned int get_lig_comp (const hb_glyph_info_t &info) { if (is_a_ligature (info)) return 0; else return info.lig_props() & 0x0F; } static inline unsigned int get_lig_num_comps (const hb_glyph_info_t &info) { if ((info.glyph_props() & HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE) && is_a_ligature (info)) return info.lig_props() & 0x0F; else return 1; } static inline uint8_t allocate_lig_id (hb_buffer_t *buffer) { uint8_t lig_id = buffer->next_serial () & 0x07; if (unlikely (!lig_id)) lig_id = allocate_lig_id (buffer); /* in case of overflow */ return lig_id; } HB_INTERNAL hb_bool_t hb_ot_layout_would_substitute_lookup_fast (hb_face_t *face, const hb_codepoint_t *glyphs, unsigned int glyphs_length, unsigned int lookup_index); /* Should be called before all the substitute_lookup's are done. */ HB_INTERNAL void hb_ot_layout_substitute_start (hb_font_t *font, hb_buffer_t *buffer); HB_INTERNAL hb_bool_t hb_ot_layout_substitute_lookup (hb_font_t *font, hb_buffer_t *buffer, unsigned int lookup_index, hb_mask_t mask); /* Should be called after all the substitute_lookup's are done */ HB_INTERNAL void hb_ot_layout_substitute_finish (hb_font_t *font, hb_buffer_t *buffer); /* Should be called before all the position_lookup's are done. Resets positions to zero. */ HB_INTERNAL void hb_ot_layout_position_start (hb_font_t *font, hb_buffer_t *buffer); HB_INTERNAL hb_bool_t hb_ot_layout_position_lookup (hb_font_t *font, hb_buffer_t *buffer, unsigned int lookup_index, hb_mask_t mask); /* Should be called after all the position_lookup's are done */ HB_INTERNAL void hb_ot_layout_position_finish (hb_font_t *font, hb_buffer_t *buffer, hb_bool_t zero_width_attached_marks); /* * hb_ot_layout_t */ struct hb_ot_layout_t { hb_blob_t *gdef_blob; hb_blob_t *gsub_blob; hb_blob_t *gpos_blob; const struct GDEF *gdef; const struct GSUB *gsub; const struct GPOS *gpos; unsigned int gsub_lookup_count; unsigned int gpos_lookup_count; hb_set_digest_t *gsub_digests; hb_set_digest_t *gpos_digests; }; HB_INTERNAL hb_ot_layout_t * _hb_ot_layout_create (hb_face_t *face); HB_INTERNAL void _hb_ot_layout_destroy (hb_ot_layout_t *layout); #endif /* HB_OT_LAYOUT_PRIVATE_HH */