1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/harfbuzz/src/hb-ot-layout-private.hh Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,423 @@
1.4 +/*
1.5 + * Copyright © 2007,2008,2009 Red Hat, Inc.
1.6 + * Copyright © 2012,2013 Google, Inc.
1.7 + *
1.8 + * This is part of HarfBuzz, a text shaping library.
1.9 + *
1.10 + * Permission is hereby granted, without written agreement and without
1.11 + * license or royalty fees, to use, copy, modify, and distribute this
1.12 + * software and its documentation for any purpose, provided that the
1.13 + * above copyright notice and the following two paragraphs appear in
1.14 + * all copies of this software.
1.15 + *
1.16 + * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
1.17 + * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
1.18 + * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
1.19 + * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
1.20 + * DAMAGE.
1.21 + *
1.22 + * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
1.23 + * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
1.24 + * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
1.25 + * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
1.26 + * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
1.27 + *
1.28 + * Red Hat Author(s): Behdad Esfahbod
1.29 + * Google Author(s): Behdad Esfahbod
1.30 + */
1.31 +
1.32 +#ifndef HB_OT_LAYOUT_PRIVATE_HH
1.33 +#define HB_OT_LAYOUT_PRIVATE_HH
1.34 +
1.35 +#include "hb-private.hh"
1.36 +
1.37 +#include "hb-font-private.hh"
1.38 +#include "hb-buffer-private.hh"
1.39 +#include "hb-set-private.hh"
1.40 +
1.41 +
1.42 +/*
1.43 + * GDEF
1.44 + */
1.45 +
1.46 +typedef enum
1.47 +{
1.48 + /* The following three match LookupFlags::Ignore* numbers. */
1.49 + HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH = 0x02u,
1.50 + HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE = 0x04u,
1.51 + HB_OT_LAYOUT_GLYPH_PROPS_MARK = 0x08u,
1.52 +
1.53 + /* The following are used internally; not derived from GDEF. */
1.54 + HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED = 0x10u,
1.55 + HB_OT_LAYOUT_GLYPH_PROPS_LIGATED = 0x20u,
1.56 +
1.57 + HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE = HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED |
1.58 + HB_OT_LAYOUT_GLYPH_PROPS_LIGATED
1.59 +} hb_ot_layout_glyph_class_mask_t;
1.60 +
1.61 +
1.62 +/*
1.63 + * GSUB/GPOS
1.64 + */
1.65 +
1.66 +HB_INTERNAL hb_bool_t
1.67 +hb_ot_layout_lookup_would_substitute_fast (hb_face_t *face,
1.68 + unsigned int lookup_index,
1.69 + const hb_codepoint_t *glyphs,
1.70 + unsigned int glyphs_length,
1.71 + hb_bool_t zero_context);
1.72 +
1.73 +
1.74 +/* Should be called before all the substitute_lookup's are done. */
1.75 +HB_INTERNAL void
1.76 +hb_ot_layout_substitute_start (hb_font_t *font,
1.77 + hb_buffer_t *buffer);
1.78 +
1.79 +
1.80 +struct hb_ot_layout_lookup_accelerator_t;
1.81 +
1.82 +namespace OT {
1.83 + struct hb_apply_context_t;
1.84 + struct SubstLookup;
1.85 +}
1.86 +
1.87 +HB_INTERNAL void
1.88 +hb_ot_layout_substitute_lookup (OT::hb_apply_context_t *c,
1.89 + const OT::SubstLookup &lookup,
1.90 + const hb_ot_layout_lookup_accelerator_t &accel);
1.91 +
1.92 +
1.93 +/* Should be called after all the substitute_lookup's are done */
1.94 +HB_INTERNAL void
1.95 +hb_ot_layout_substitute_finish (hb_font_t *font,
1.96 + hb_buffer_t *buffer);
1.97 +
1.98 +
1.99 +/* Should be called before all the position_lookup's are done. Resets positions to zero. */
1.100 +HB_INTERNAL void
1.101 +hb_ot_layout_position_start (hb_font_t *font,
1.102 + hb_buffer_t *buffer);
1.103 +
1.104 +/* Should be called after all the position_lookup's are done */
1.105 +HB_INTERNAL void
1.106 +hb_ot_layout_position_finish (hb_font_t *font,
1.107 + hb_buffer_t *buffer);
1.108 +
1.109 +
1.110 +
1.111 +/*
1.112 + * hb_ot_layout_t
1.113 + */
1.114 +
1.115 +namespace OT {
1.116 + struct GDEF;
1.117 + struct GSUB;
1.118 + struct GPOS;
1.119 +}
1.120 +
1.121 +struct hb_ot_layout_lookup_accelerator_t
1.122 +{
1.123 + template <typename TLookup>
1.124 + inline void init (const TLookup &lookup)
1.125 + {
1.126 + digest.init ();
1.127 + lookup.add_coverage (&digest);
1.128 + }
1.129 +
1.130 + template <typename TLookup>
1.131 + inline void fini (const TLookup &lookup)
1.132 + {
1.133 + }
1.134 +
1.135 + hb_set_digest_t digest;
1.136 +};
1.137 +
1.138 +struct hb_ot_layout_t
1.139 +{
1.140 + hb_blob_t *gdef_blob;
1.141 + hb_blob_t *gsub_blob;
1.142 + hb_blob_t *gpos_blob;
1.143 +
1.144 + const struct OT::GDEF *gdef;
1.145 + const struct OT::GSUB *gsub;
1.146 + const struct OT::GPOS *gpos;
1.147 +
1.148 + unsigned int gsub_lookup_count;
1.149 + unsigned int gpos_lookup_count;
1.150 +
1.151 + hb_ot_layout_lookup_accelerator_t *gsub_accels;
1.152 + hb_ot_layout_lookup_accelerator_t *gpos_accels;
1.153 +};
1.154 +
1.155 +
1.156 +HB_INTERNAL hb_ot_layout_t *
1.157 +_hb_ot_layout_create (hb_face_t *face);
1.158 +
1.159 +HB_INTERNAL void
1.160 +_hb_ot_layout_destroy (hb_ot_layout_t *layout);
1.161 +
1.162 +
1.163 +#define hb_ot_layout_from_face(face) ((hb_ot_layout_t *) face->shaper_data.ot)
1.164 +
1.165 +
1.166 +/*
1.167 + * Buffer var routines.
1.168 + */
1.169 +
1.170 +/* buffer var allocations, used during the entire shaping process */
1.171 +#define unicode_props0() var2.u8[0]
1.172 +#define unicode_props1() var2.u8[1]
1.173 +
1.174 +/* buffer var allocations, used during the GSUB/GPOS processing */
1.175 +#define glyph_props() var1.u16[0] /* GDEF glyph properties */
1.176 +#define lig_props() var1.u8[2] /* GSUB/GPOS ligature tracking */
1.177 +#define syllable() var1.u8[3] /* GSUB/GPOS shaping boundaries */
1.178 +
1.179 +/* unicode_props */
1.180 +
1.181 +enum {
1.182 + MASK0_ZWJ = 0x20u,
1.183 + MASK0_ZWNJ = 0x40u,
1.184 + MASK0_IGNORABLE = 0x80u,
1.185 + MASK0_GEN_CAT = 0x1Fu
1.186 +};
1.187 +
1.188 +inline void
1.189 +_hb_glyph_info_set_unicode_props (hb_glyph_info_t *info, hb_unicode_funcs_t *unicode)
1.190 +{
1.191 + /* XXX This shouldn't be inlined, or at least not while is_default_ignorable() is inline. */
1.192 + info->unicode_props0() = ((unsigned int) unicode->general_category (info->codepoint)) |
1.193 + (unicode->is_default_ignorable (info->codepoint) ? MASK0_IGNORABLE : 0) |
1.194 + (info->codepoint == 0x200C ? MASK0_ZWNJ : 0) |
1.195 + (info->codepoint == 0x200D ? MASK0_ZWJ : 0);
1.196 + info->unicode_props1() = unicode->modified_combining_class (info->codepoint);
1.197 +}
1.198 +
1.199 +inline void
1.200 +_hb_glyph_info_set_general_category (hb_glyph_info_t *info,
1.201 + hb_unicode_general_category_t gen_cat)
1.202 +{
1.203 + info->unicode_props0() = (unsigned int) gen_cat | ((info->unicode_props0()) & ~MASK0_GEN_CAT);
1.204 +}
1.205 +
1.206 +inline hb_unicode_general_category_t
1.207 +_hb_glyph_info_get_general_category (const hb_glyph_info_t *info)
1.208 +{
1.209 + return (hb_unicode_general_category_t) (info->unicode_props0() & MASK0_GEN_CAT);
1.210 +}
1.211 +
1.212 +inline void
1.213 +_hb_glyph_info_set_modified_combining_class (hb_glyph_info_t *info,
1.214 + unsigned int modified_class)
1.215 +{
1.216 + info->unicode_props1() = modified_class;
1.217 +}
1.218 +
1.219 +inline unsigned int
1.220 +_hb_glyph_info_get_modified_combining_class (const hb_glyph_info_t *info)
1.221 +{
1.222 + return info->unicode_props1();
1.223 +}
1.224 +
1.225 +inline hb_bool_t
1.226 +_hb_glyph_info_is_default_ignorable (const hb_glyph_info_t *info)
1.227 +{
1.228 + return !!(info->unicode_props0() & MASK0_IGNORABLE);
1.229 +}
1.230 +
1.231 +inline hb_bool_t
1.232 +_hb_glyph_info_is_zwnj (const hb_glyph_info_t *info)
1.233 +{
1.234 + return !!(info->unicode_props0() & MASK0_ZWNJ);
1.235 +}
1.236 +
1.237 +inline hb_bool_t
1.238 +_hb_glyph_info_is_zwj (const hb_glyph_info_t *info)
1.239 +{
1.240 + return !!(info->unicode_props0() & MASK0_ZWJ);
1.241 +}
1.242 +
1.243 +inline void
1.244 +_hb_glyph_info_flip_joiners (hb_glyph_info_t *info)
1.245 +{
1.246 + info->unicode_props0() ^= MASK0_ZWNJ | MASK0_ZWJ;
1.247 +}
1.248 +
1.249 +/* lig_props: aka lig_id / lig_comp
1.250 + *
1.251 + * When a ligature is formed:
1.252 + *
1.253 + * - The ligature glyph and any marks in between all the same newly allocated
1.254 + * lig_id,
1.255 + * - The ligature glyph will get lig_num_comps set to the number of components
1.256 + * - The marks get lig_comp > 0, reflecting which component of the ligature
1.257 + * they were applied to.
1.258 + * - This is used in GPOS to attach marks to the right component of a ligature
1.259 + * in MarkLigPos,
1.260 + * - Note that when marks are ligated together, much of the above is skipped
1.261 + * and the current lig_id reused.
1.262 + *
1.263 + * When a multiple-substitution is done:
1.264 + *
1.265 + * - All resulting glyphs will have lig_id = 0,
1.266 + * - The resulting glyphs will have lig_comp = 0, 1, 2, ... respectively.
1.267 + * - This is used in GPOS to attach marks to the first component of a
1.268 + * multiple substitution in MarkBasePos.
1.269 + *
1.270 + * The numbers are also used in GPOS to do mark-to-mark positioning only
1.271 + * to marks that belong to the same component of the same ligature.
1.272 + */
1.273 +
1.274 +static inline void
1.275 +_hb_glyph_info_clear_lig_props (hb_glyph_info_t *info)
1.276 +{
1.277 + info->lig_props() = 0;
1.278 +}
1.279 +
1.280 +#define IS_LIG_BASE 0x10
1.281 +
1.282 +static inline void
1.283 +_hb_glyph_info_set_lig_props_for_ligature (hb_glyph_info_t *info,
1.284 + unsigned int lig_id,
1.285 + unsigned int lig_num_comps)
1.286 +{
1.287 + info->lig_props() = (lig_id << 5) | IS_LIG_BASE | (lig_num_comps & 0x0F);
1.288 +}
1.289 +
1.290 +static inline void
1.291 +_hb_glyph_info_set_lig_props_for_mark (hb_glyph_info_t *info,
1.292 + unsigned int lig_id,
1.293 + unsigned int lig_comp)
1.294 +{
1.295 + info->lig_props() = (lig_id << 5) | (lig_comp & 0x0F);
1.296 +}
1.297 +
1.298 +static inline void
1.299 +_hb_glyph_info_set_lig_props_for_component (hb_glyph_info_t *info, unsigned int comp)
1.300 +{
1.301 + _hb_glyph_info_set_lig_props_for_mark (info, 0, comp);
1.302 +}
1.303 +
1.304 +static inline unsigned int
1.305 +_hb_glyph_info_get_lig_id (const hb_glyph_info_t *info)
1.306 +{
1.307 + return info->lig_props() >> 5;
1.308 +}
1.309 +
1.310 +static inline bool
1.311 +_hb_glyph_info_ligated_internal (const hb_glyph_info_t *info)
1.312 +{
1.313 + return !!(info->lig_props() & IS_LIG_BASE);
1.314 +}
1.315 +
1.316 +static inline unsigned int
1.317 +_hb_glyph_info_get_lig_comp (const hb_glyph_info_t *info)
1.318 +{
1.319 + if (_hb_glyph_info_ligated_internal (info))
1.320 + return 0;
1.321 + else
1.322 + return info->lig_props() & 0x0F;
1.323 +}
1.324 +
1.325 +static inline unsigned int
1.326 +_hb_glyph_info_get_lig_num_comps (const hb_glyph_info_t *info)
1.327 +{
1.328 + if ((info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE) &&
1.329 + _hb_glyph_info_ligated_internal (info))
1.330 + return info->lig_props() & 0x0F;
1.331 + else
1.332 + return 1;
1.333 +}
1.334 +
1.335 +static inline uint8_t
1.336 +_hb_allocate_lig_id (hb_buffer_t *buffer) {
1.337 + uint8_t lig_id = buffer->next_serial () & 0x07;
1.338 + if (unlikely (!lig_id))
1.339 + lig_id = _hb_allocate_lig_id (buffer); /* in case of overflow */
1.340 + return lig_id;
1.341 +}
1.342 +
1.343 +/* glyph_props: */
1.344 +
1.345 +inline void
1.346 +_hb_glyph_info_set_glyph_props (hb_glyph_info_t *info, unsigned int props)
1.347 +{
1.348 + info->glyph_props() = props;
1.349 +}
1.350 +
1.351 +inline unsigned int
1.352 +_hb_glyph_info_get_glyph_props (const hb_glyph_info_t *info)
1.353 +{
1.354 + return info->glyph_props();
1.355 +}
1.356 +
1.357 +inline bool
1.358 +_hb_glyph_info_is_base_glyph (const hb_glyph_info_t *info)
1.359 +{
1.360 + return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH);
1.361 +}
1.362 +
1.363 +inline bool
1.364 +_hb_glyph_info_is_ligature (const hb_glyph_info_t *info)
1.365 +{
1.366 + return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE);
1.367 +}
1.368 +
1.369 +inline bool
1.370 +_hb_glyph_info_is_mark (const hb_glyph_info_t *info)
1.371 +{
1.372 + return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_MARK);
1.373 +}
1.374 +
1.375 +static inline bool
1.376 +_hb_glyph_info_substituted (const hb_glyph_info_t *info)
1.377 +{
1.378 + return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED);
1.379 +}
1.380 +
1.381 +static inline bool
1.382 +_hb_glyph_info_ligated (const hb_glyph_info_t *info)
1.383 +{
1.384 + return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_LIGATED);
1.385 +}
1.386 +
1.387 +/* Allocation / deallocation. */
1.388 +
1.389 +inline void
1.390 +_hb_buffer_allocate_unicode_vars (hb_buffer_t *buffer)
1.391 +{
1.392 + HB_BUFFER_ALLOCATE_VAR (buffer, unicode_props0);
1.393 + HB_BUFFER_ALLOCATE_VAR (buffer, unicode_props1);
1.394 +}
1.395 +
1.396 +inline void
1.397 +_hb_buffer_deallocate_unicode_vars (hb_buffer_t *buffer)
1.398 +{
1.399 + HB_BUFFER_DEALLOCATE_VAR (buffer, unicode_props0);
1.400 + HB_BUFFER_DEALLOCATE_VAR (buffer, unicode_props1);
1.401 +}
1.402 +
1.403 +inline void
1.404 +_hb_buffer_allocate_gsubgpos_vars (hb_buffer_t *buffer)
1.405 +{
1.406 + HB_BUFFER_ALLOCATE_VAR (buffer, glyph_props);
1.407 + HB_BUFFER_ALLOCATE_VAR (buffer, lig_props);
1.408 + HB_BUFFER_ALLOCATE_VAR (buffer, syllable);
1.409 +}
1.410 +
1.411 +inline void
1.412 +_hb_buffer_deallocate_gsubgpos_vars (hb_buffer_t *buffer)
1.413 +{
1.414 + HB_BUFFER_DEALLOCATE_VAR (buffer, syllable);
1.415 + HB_BUFFER_DEALLOCATE_VAR (buffer, lig_props);
1.416 + HB_BUFFER_DEALLOCATE_VAR (buffer, glyph_props);
1.417 +}
1.418 +
1.419 +/* Make sure no one directly touches our props... */
1.420 +#undef unicode_props0
1.421 +#undef unicode_props1
1.422 +#undef lig_props
1.423 +#undef glyph_props
1.424 +
1.425 +
1.426 +#endif /* HB_OT_LAYOUT_PRIVATE_HH */
