gfx/harfbuzz/src/hb-aat-layout-ankr-table.hh

   1 /*
   2  * Copyright © 2018  Ebrahim Byagowi
   3  *
   4  *  This is part of HarfBuzz, a text shaping library.
   5  *
   6  * Permission is hereby granted, without written agreement and without
   7  * license or royalty fees, to use, copy, modify, and distribute this
   8  * software and its documentation for any purpose, provided that the
   9  * above copyright notice and the following two paragraphs appear in
  10  * all copies of this software.
  11  *
  12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  16  * DAMAGE.
  17  *
  18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  23  */
  24
  25 #ifndef HB_AAT_LAYOUT_ANKR_TABLE_HH
  26 #define HB_AAT_LAYOUT_ANKR_TABLE_HH
  27
  28 #include "hb-aat-layout-common.hh"
  29
  30 /*
  31  * ankr -- Anchor Point
  32  * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6ankr.html
  33  */
  34 #define HB_AAT_TAG_ankr HB_TAG('a','n','k','r')
  35
  36
  37 namespace AAT {
  38
  39 using namespace OT;
  40
  41
  42 struct Anchor
  43 {
  44   bool sanitize (hb_sanitize_context_t *c) const
  45   {
  46     TRACE_SANITIZE (this);
  47     return_trace (c->check_struct (this));
  48   }
  49
  50   public:
  51   FWORD         xCoordinate;
  52   FWORD         yCoordinate;
  53   public:
  54   DEFINE_SIZE_STATIC (4);
  55 };
  56
  57 typedef Array32Of<Anchor> GlyphAnchors;
  58
  59 struct ankr
  60 {
  61   static constexpr hb_tag_t tableTag = HB_AAT_TAG_ankr;
  62
  63   const Anchor &get_anchor (hb_codepoint_t glyph_id,
  64                             unsigned int i,
  65                             unsigned int num_glyphs) const
  66   {
  67     const NNOffset16To<GlyphAnchors> *offset = (this+lookupTable).get_value (glyph_id, num_glyphs);
  68     if (!offset)
  69       return Null (Anchor);
  70     const GlyphAnchors &anchors = &(this+anchorData) + *offset;
  71     return anchors[i];
  72   }
  73
  74   bool sanitize (hb_sanitize_context_t *c) const
  75   {
  76     TRACE_SANITIZE (this);
  77     return_trace (likely (c->check_struct (this) &&
  78                           hb_barrier () &&
  79                           version == 0 &&
  80                           c->check_range (this, anchorData) &&
  81                           lookupTable.sanitize (c, this, &(this+anchorData))));
  82   }
  83
  84   protected:
  85   HBUINT16      version;        /* Version number (set to zero) */
  86   HBUINT16      flags;          /* Flags (currently unused; set to zero) */
  87   Offset32To<Lookup<NNOffset16To<GlyphAnchors>>>
  88                 lookupTable;    /* Offset to the table's lookup table */
  89   NNOffset32To<HBUINT8>
  90                 anchorData;     /* Offset to the glyph data table */
  91
  92   public:
  93   DEFINE_SIZE_STATIC (12);
  94 };
  95
  96 } /* namespace AAT */
  97
  98
  99 #endif /* HB_AAT_LAYOUT_ANKR_TABLE_HH */