1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/harfbuzz/src/hb-ft.cc Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,522 @@
1.4 +/*
1.5 + * Copyright © 2009 Red Hat, Inc.
1.6 + * Copyright © 2009 Keith Stribley
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 + */
1.30 +
1.31 +#include "hb-private.hh"
1.32 +
1.33 +#include "hb-ft.h"
1.34 +
1.35 +#include "hb-font-private.hh"
1.36 +
1.37 +#include FT_ADVANCES_H
1.38 +#include FT_TRUETYPE_TABLES_H
1.39 +
1.40 +
1.41 +
1.42 +#ifndef HB_DEBUG_FT
1.43 +#define HB_DEBUG_FT (HB_DEBUG+0)
1.44 +#endif
1.45 +
1.46 +
1.47 +/* TODO:
1.48 + *
1.49 + * In general, this file does a fine job of what it's supposed to do.
1.50 + * There are, however, things that need more work:
1.51 + *
1.52 + * - We don't handle any load_flags. That definitely has API implications. :(
1.53 + * I believe hb_ft_font_create() should take load_flags input.
1.54 + * In particular, FT_Get_Advance() without the NO_HINTING flag seems to be
1.55 + * buggy.
1.56 + *
1.57 + * - We don't handle / allow for emboldening / obliqueing.
1.58 + *
1.59 + * - In the future, we should add constructors to create fonts in font space?
1.60 + *
1.61 + * - FT_Load_Glyph() is exteremely costly. Do something about it?
1.62 + */
1.63 +
1.64 +
1.65 +static hb_bool_t
1.66 +hb_ft_get_glyph (hb_font_t *font HB_UNUSED,
1.67 + void *font_data,
1.68 + hb_codepoint_t unicode,
1.69 + hb_codepoint_t variation_selector,
1.70 + hb_codepoint_t *glyph,
1.71 + void *user_data HB_UNUSED)
1.72 +
1.73 +{
1.74 + FT_Face ft_face = (FT_Face) font_data;
1.75 +
1.76 +#ifdef HAVE_FT_FACE_GETCHARVARIANTINDEX
1.77 + if (unlikely (variation_selector)) {
1.78 + *glyph = FT_Face_GetCharVariantIndex (ft_face, unicode, variation_selector);
1.79 + return *glyph != 0;
1.80 + }
1.81 +#endif
1.82 +
1.83 + *glyph = FT_Get_Char_Index (ft_face, unicode);
1.84 + return *glyph != 0;
1.85 +}
1.86 +
1.87 +static hb_position_t
1.88 +hb_ft_get_glyph_h_advance (hb_font_t *font HB_UNUSED,
1.89 + void *font_data,
1.90 + hb_codepoint_t glyph,
1.91 + void *user_data HB_UNUSED)
1.92 +{
1.93 + FT_Face ft_face = (FT_Face) font_data;
1.94 + int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING;
1.95 + FT_Fixed v;
1.96 +
1.97 + if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v)))
1.98 + return 0;
1.99 +
1.100 + return (v + (1<<9)) >> 10;
1.101 +}
1.102 +
1.103 +static hb_position_t
1.104 +hb_ft_get_glyph_v_advance (hb_font_t *font HB_UNUSED,
1.105 + void *font_data,
1.106 + hb_codepoint_t glyph,
1.107 + void *user_data HB_UNUSED)
1.108 +{
1.109 + FT_Face ft_face = (FT_Face) font_data;
1.110 + int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING | FT_LOAD_VERTICAL_LAYOUT;
1.111 + FT_Fixed v;
1.112 +
1.113 + if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v)))
1.114 + return 0;
1.115 +
1.116 + /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
1.117 + * have a Y growing upward. Hence the extra negation. */
1.118 + return (-v + (1<<9)) >> 10;
1.119 +}
1.120 +
1.121 +static hb_bool_t
1.122 +hb_ft_get_glyph_h_origin (hb_font_t *font HB_UNUSED,
1.123 + void *font_data HB_UNUSED,
1.124 + hb_codepoint_t glyph HB_UNUSED,
1.125 + hb_position_t *x HB_UNUSED,
1.126 + hb_position_t *y HB_UNUSED,
1.127 + void *user_data HB_UNUSED)
1.128 +{
1.129 + /* We always work in the horizontal coordinates. */
1.130 + return true;
1.131 +}
1.132 +
1.133 +static hb_bool_t
1.134 +hb_ft_get_glyph_v_origin (hb_font_t *font HB_UNUSED,
1.135 + void *font_data,
1.136 + hb_codepoint_t glyph,
1.137 + hb_position_t *x,
1.138 + hb_position_t *y,
1.139 + void *user_data HB_UNUSED)
1.140 +{
1.141 + FT_Face ft_face = (FT_Face) font_data;
1.142 + int load_flags = FT_LOAD_DEFAULT;
1.143 +
1.144 + if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
1.145 + return false;
1.146 +
1.147 + /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
1.148 + * have a Y growing upward. Hence the extra negation. */
1.149 + *x = ft_face->glyph->metrics.horiBearingX - ft_face->glyph->metrics.vertBearingX;
1.150 + *y = ft_face->glyph->metrics.horiBearingY - (-ft_face->glyph->metrics.vertBearingY);
1.151 +
1.152 + return true;
1.153 +}
1.154 +
1.155 +static hb_position_t
1.156 +hb_ft_get_glyph_h_kerning (hb_font_t *font,
1.157 + void *font_data,
1.158 + hb_codepoint_t left_glyph,
1.159 + hb_codepoint_t right_glyph,
1.160 + void *user_data HB_UNUSED)
1.161 +{
1.162 + FT_Face ft_face = (FT_Face) font_data;
1.163 + FT_Vector kerningv;
1.164 +
1.165 + FT_Kerning_Mode mode = font->x_ppem ? FT_KERNING_DEFAULT : FT_KERNING_UNFITTED;
1.166 + if (FT_Get_Kerning (ft_face, left_glyph, right_glyph, mode, &kerningv))
1.167 + return 0;
1.168 +
1.169 + return kerningv.x;
1.170 +}
1.171 +
1.172 +static hb_position_t
1.173 +hb_ft_get_glyph_v_kerning (hb_font_t *font HB_UNUSED,
1.174 + void *font_data HB_UNUSED,
1.175 + hb_codepoint_t top_glyph HB_UNUSED,
1.176 + hb_codepoint_t bottom_glyph HB_UNUSED,
1.177 + void *user_data HB_UNUSED)
1.178 +{
1.179 + /* FreeType API doesn't support vertical kerning */
1.180 + return 0;
1.181 +}
1.182 +
1.183 +static hb_bool_t
1.184 +hb_ft_get_glyph_extents (hb_font_t *font HB_UNUSED,
1.185 + void *font_data,
1.186 + hb_codepoint_t glyph,
1.187 + hb_glyph_extents_t *extents,
1.188 + void *user_data HB_UNUSED)
1.189 +{
1.190 + FT_Face ft_face = (FT_Face) font_data;
1.191 + int load_flags = FT_LOAD_DEFAULT;
1.192 +
1.193 + if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
1.194 + return false;
1.195 +
1.196 + extents->x_bearing = ft_face->glyph->metrics.horiBearingX;
1.197 + extents->y_bearing = ft_face->glyph->metrics.horiBearingY;
1.198 + extents->width = ft_face->glyph->metrics.width;
1.199 + extents->height = -ft_face->glyph->metrics.height;
1.200 + return true;
1.201 +}
1.202 +
1.203 +static hb_bool_t
1.204 +hb_ft_get_glyph_contour_point (hb_font_t *font HB_UNUSED,
1.205 + void *font_data,
1.206 + hb_codepoint_t glyph,
1.207 + unsigned int point_index,
1.208 + hb_position_t *x,
1.209 + hb_position_t *y,
1.210 + void *user_data HB_UNUSED)
1.211 +{
1.212 + FT_Face ft_face = (FT_Face) font_data;
1.213 + int load_flags = FT_LOAD_DEFAULT;
1.214 +
1.215 + if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
1.216 + return false;
1.217 +
1.218 + if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE))
1.219 + return false;
1.220 +
1.221 + if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points))
1.222 + return false;
1.223 +
1.224 + *x = ft_face->glyph->outline.points[point_index].x;
1.225 + *y = ft_face->glyph->outline.points[point_index].y;
1.226 +
1.227 + return true;
1.228 +}
1.229 +
1.230 +static hb_bool_t
1.231 +hb_ft_get_glyph_name (hb_font_t *font HB_UNUSED,
1.232 + void *font_data,
1.233 + hb_codepoint_t glyph,
1.234 + char *name, unsigned int size,
1.235 + void *user_data HB_UNUSED)
1.236 +{
1.237 + FT_Face ft_face = (FT_Face) font_data;
1.238 +
1.239 + hb_bool_t ret = !FT_Get_Glyph_Name (ft_face, glyph, name, size);
1.240 + if (ret && (size && !*name))
1.241 + ret = false;
1.242 +
1.243 + return ret;
1.244 +}
1.245 +
1.246 +static hb_bool_t
1.247 +hb_ft_get_glyph_from_name (hb_font_t *font HB_UNUSED,
1.248 + void *font_data,
1.249 + const char *name, int len, /* -1 means nul-terminated */
1.250 + hb_codepoint_t *glyph,
1.251 + void *user_data HB_UNUSED)
1.252 +{
1.253 + FT_Face ft_face = (FT_Face) font_data;
1.254 +
1.255 + if (len < 0)
1.256 + *glyph = FT_Get_Name_Index (ft_face, (FT_String *) name);
1.257 + else {
1.258 + /* Make a nul-terminated version. */
1.259 + char buf[128];
1.260 + len = MIN (len, (int) sizeof (buf) - 1);
1.261 + strncpy (buf, name, len);
1.262 + buf[len] = '\0';
1.263 + *glyph = FT_Get_Name_Index (ft_face, buf);
1.264 + }
1.265 +
1.266 + if (*glyph == 0)
1.267 + {
1.268 + /* Check whether the given name was actually the name of glyph 0. */
1.269 + char buf[128];
1.270 + if (!FT_Get_Glyph_Name(ft_face, 0, buf, sizeof (buf)) &&
1.271 + len < 0 ? !strcmp (buf, name) : !strncmp (buf, name, len))
1.272 + return true;
1.273 + }
1.274 +
1.275 + return *glyph != 0;
1.276 +}
1.277 +
1.278 +
1.279 +static hb_font_funcs_t *
1.280 +_hb_ft_get_font_funcs (void)
1.281 +{
1.282 + static const hb_font_funcs_t ft_ffuncs = {
1.283 + HB_OBJECT_HEADER_STATIC,
1.284 +
1.285 + true, /* immutable */
1.286 +
1.287 + {
1.288 +#define HB_FONT_FUNC_IMPLEMENT(name) hb_ft_get_##name,
1.289 + HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
1.290 +#undef HB_FONT_FUNC_IMPLEMENT
1.291 + }
1.292 + };
1.293 +
1.294 + return const_cast<hb_font_funcs_t *> (&ft_ffuncs);
1.295 +}
1.296 +
1.297 +
1.298 +static hb_blob_t *
1.299 +reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
1.300 +{
1.301 + FT_Face ft_face = (FT_Face) user_data;
1.302 + FT_Byte *buffer;
1.303 + FT_ULong length = 0;
1.304 + FT_Error error;
1.305 +
1.306 + /* Note: FreeType like HarfBuzz uses the NONE tag for fetching the entire blob */
1.307 +
1.308 + error = FT_Load_Sfnt_Table (ft_face, tag, 0, NULL, &length);
1.309 + if (error)
1.310 + return NULL;
1.311 +
1.312 + buffer = (FT_Byte *) malloc (length);
1.313 + if (buffer == NULL)
1.314 + return NULL;
1.315 +
1.316 + error = FT_Load_Sfnt_Table (ft_face, tag, 0, buffer, &length);
1.317 + if (error)
1.318 + return NULL;
1.319 +
1.320 + return hb_blob_create ((const char *) buffer, length,
1.321 + HB_MEMORY_MODE_WRITABLE,
1.322 + buffer, free);
1.323 +}
1.324 +
1.325 +/**
1.326 + * hb_ft_face_create:
1.327 + * @ft_face: (destroy destroy) (scope notified):
1.328 + * @destroy:
1.329 + *
1.330 + *
1.331 + *
1.332 + * Return value: (transfer full):
1.333 + * Since: 1.0
1.334 + **/
1.335 +hb_face_t *
1.336 +hb_ft_face_create (FT_Face ft_face,
1.337 + hb_destroy_func_t destroy)
1.338 +{
1.339 + hb_face_t *face;
1.340 +
1.341 + if (ft_face->stream->read == NULL) {
1.342 + hb_blob_t *blob;
1.343 +
1.344 + blob = hb_blob_create ((const char *) ft_face->stream->base,
1.345 + (unsigned int) ft_face->stream->size,
1.346 + /* TODO: We assume that it's mmap()'ed, but FreeType code
1.347 + * suggests that there are cases we reach here but font is
1.348 + * not mmapped. For example, when mmap() fails. No idea
1.349 + * how to deal with it better here. */
1.350 + HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE,
1.351 + ft_face, destroy);
1.352 + face = hb_face_create (blob, ft_face->face_index);
1.353 + hb_blob_destroy (blob);
1.354 + } else {
1.355 + face = hb_face_create_for_tables (reference_table, ft_face, destroy);
1.356 + }
1.357 +
1.358 + hb_face_set_index (face, ft_face->face_index);
1.359 + hb_face_set_upem (face, ft_face->units_per_EM);
1.360 +
1.361 + return face;
1.362 +}
1.363 +
1.364 +static void
1.365 +hb_ft_face_finalize (FT_Face ft_face)
1.366 +{
1.367 + hb_face_destroy ((hb_face_t *) ft_face->generic.data);
1.368 +}
1.369 +
1.370 +/**
1.371 + * hb_ft_face_create_cached:
1.372 + * @ft_face:
1.373 + *
1.374 + *
1.375 + *
1.376 + * Return value: (transfer full):
1.377 + * Since: 1.0
1.378 + **/
1.379 +hb_face_t *
1.380 +hb_ft_face_create_cached (FT_Face ft_face)
1.381 +{
1.382 + if (unlikely (!ft_face->generic.data || ft_face->generic.finalizer != (FT_Generic_Finalizer) hb_ft_face_finalize))
1.383 + {
1.384 + if (ft_face->generic.finalizer)
1.385 + ft_face->generic.finalizer (ft_face);
1.386 +
1.387 + ft_face->generic.data = hb_ft_face_create (ft_face, NULL);
1.388 + ft_face->generic.finalizer = (FT_Generic_Finalizer) hb_ft_face_finalize;
1.389 + }
1.390 +
1.391 + return hb_face_reference ((hb_face_t *) ft_face->generic.data);
1.392 +}
1.393 +
1.394 +static void
1.395 +_do_nothing (void)
1.396 +{
1.397 +}
1.398 +
1.399 +
1.400 +/**
1.401 + * hb_ft_font_create:
1.402 + * @ft_face: (destroy destroy) (scope notified):
1.403 + * @destroy:
1.404 + *
1.405 + *
1.406 + *
1.407 + * Return value: (transfer full):
1.408 + * Since: 1.0
1.409 + **/
1.410 +hb_font_t *
1.411 +hb_ft_font_create (FT_Face ft_face,
1.412 + hb_destroy_func_t destroy)
1.413 +{
1.414 + hb_font_t *font;
1.415 + hb_face_t *face;
1.416 +
1.417 + face = hb_ft_face_create (ft_face, destroy);
1.418 + font = hb_font_create (face);
1.419 + hb_face_destroy (face);
1.420 + hb_font_set_funcs (font,
1.421 + _hb_ft_get_font_funcs (),
1.422 + ft_face, (hb_destroy_func_t) _do_nothing);
1.423 + hb_font_set_scale (font,
1.424 + (int) (((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM + (1<<15)) >> 16),
1.425 + (int) (((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM + (1<<15)) >> 16));
1.426 + hb_font_set_ppem (font,
1.427 + ft_face->size->metrics.x_ppem,
1.428 + ft_face->size->metrics.y_ppem);
1.429 +
1.430 + return font;
1.431 +}
1.432 +
1.433 +
1.434 +/* Thread-safe, lock-free, FT_Library */
1.435 +
1.436 +static FT_Library ft_library;
1.437 +
1.438 +static inline
1.439 +void free_ft_library (void)
1.440 +{
1.441 + FT_Done_FreeType (ft_library);
1.442 +}
1.443 +
1.444 +static FT_Library
1.445 +get_ft_library (void)
1.446 +{
1.447 +retry:
1.448 + FT_Library library = (FT_Library) hb_atomic_ptr_get (&ft_library);
1.449 +
1.450 + if (unlikely (!library))
1.451 + {
1.452 + /* Not found; allocate one. */
1.453 + if (FT_Init_FreeType (&library))
1.454 + return NULL;
1.455 +
1.456 + if (!hb_atomic_ptr_cmpexch (&ft_library, NULL, library)) {
1.457 + FT_Done_FreeType (library);
1.458 + goto retry;
1.459 + }
1.460 +
1.461 +#ifdef HAVE_ATEXIT
1.462 + atexit (free_ft_library); /* First person registers atexit() callback. */
1.463 +#endif
1.464 + }
1.465 +
1.466 + return library;
1.467 +}
1.468 +
1.469 +static void
1.470 +_release_blob (FT_Face ft_face)
1.471 +{
1.472 + hb_blob_destroy ((hb_blob_t *) ft_face->generic.data);
1.473 +}
1.474 +
1.475 +void
1.476 +hb_ft_font_set_funcs (hb_font_t *font)
1.477 +{
1.478 + hb_blob_t *blob = hb_face_reference_blob (font->face);
1.479 + unsigned int blob_length;
1.480 + const char *blob_data = hb_blob_get_data (blob, &blob_length);
1.481 + if (unlikely (!blob_length))
1.482 + DEBUG_MSG (FT, font, "Font face has empty blob");
1.483 +
1.484 + FT_Face ft_face = NULL;
1.485 + FT_Error err = FT_New_Memory_Face (get_ft_library (),
1.486 + (const FT_Byte *) blob_data,
1.487 + blob_length,
1.488 + hb_face_get_index (font->face),
1.489 + &ft_face);
1.490 +
1.491 + if (unlikely (err)) {
1.492 + hb_blob_destroy (blob);
1.493 + DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed");
1.494 + return;
1.495 + }
1.496 +
1.497 + FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE);
1.498 +
1.499 + assert (font->y_scale >= 0);
1.500 + FT_Set_Char_Size (ft_face,
1.501 + font->x_scale, font->y_scale,
1.502 + 0, 0);
1.503 +#if 0
1.504 + font->x_ppem * 72 * 64 / font->x_scale,
1.505 + font->y_ppem * 72 * 64 / font->y_scale);
1.506 +#endif
1.507 +
1.508 + ft_face->generic.data = blob;
1.509 + ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob;
1.510 +
1.511 + hb_font_set_funcs (font,
1.512 + _hb_ft_get_font_funcs (),
1.513 + ft_face,
1.514 + (hb_destroy_func_t) FT_Done_Face);
1.515 +}
1.516 +
1.517 +FT_Face
1.518 +hb_ft_font_get_face (hb_font_t *font)
1.519 +{
1.520 + if (font->destroy == (hb_destroy_func_t) FT_Done_Face ||
1.521 + font->destroy == (hb_destroy_func_t) _do_nothing)
1.522 + return (FT_Face) font->user_data;
1.523 +
1.524 + return NULL;
1.525 +}
