1 /*

     2  * Copyright © 2011,2012  Google, Inc.

     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  * Google Author(s): Behdad Esfahbod

    25  */

    26 

    27 #ifndef HB_OT_HMTX_TABLE_HH

    28 #define HB_OT_HMTX_TABLE_HH

    29 

    30 #include "hb-open-type-private.hh"

    31 

    32 

    33 namespace OT {

    34 

    35 

    36 /*

    37  * hmtx -- The Horizontal Metrics Table

    38  * vmtx -- The Vertical Metrics Table

    39  */

    40 

    41 #define HB_OT_TAG_hmtx HB_TAG('h','m','t','x')

    42 #define HB_OT_TAG_vmtx HB_TAG('v','m','t','x')

    43 

    44 

    45 struct LongMetric

    46 {

    47   UFWORD        advance; /* Advance width/height. */

    48   FWORD         lsb; /* Leading (left/top) side bearing. */

    49   public:

    50   DEFINE_SIZE_STATIC (4);

    51 };

    52 

    53 struct _mtx

    54 {

    55   static const hb_tag_t tableTag = HB_TAG('_','m','t','x');

    56 

    57   static const hb_tag_t hmtxTag = HB_OT_TAG_hmtx;

    58   static const hb_tag_t vmtxTag = HB_OT_TAG_vmtx;

    59 

    60   inline bool sanitize (hb_sanitize_context_t *c) const

    61   {

    62     TRACE_SANITIZE (this);

    63     /* We don't check for anything specific here.  The users of the

    64      * struct do all the hard work... */

    65     return_trace (true);

    66   }

    67 

    68   public:

    69   LongMetric    longMetric[VAR];        /* Paired advance width and leading

    70                                          * bearing values for each glyph. The

    71                                          * value numOfHMetrics comes from

    72                                          * the 'hhea' table. If the font is

    73                                          * monospaced, only one entry need

    74                                          * be in the array, but that entry is

    75                                          * required. The last entry applies to

    76                                          * all subsequent glyphs. */

    77   FWORD         leadingBearingX[VAR];   /* Here the advance is assumed

    78                                          * to be the same as the advance

    79                                          * for the last entry above. The

    80                                          * number of entries in this array is

    81                                          * derived from numGlyphs (from 'maxp'

    82                                          * table) minus numberOfLongMetrics.

    83                                          * This generally is used with a run

    84                                          * of monospaced glyphs (e.g., Kanji

    85                                          * fonts or Courier fonts). Only one

    86                                          * run is allowed and it must be at

    87                                          * the end. This allows a monospaced

    88                                          * font to vary the side bearing

    89                                          * values for each glyph. */

    90   public:

    91   DEFINE_SIZE_ARRAY2 (0, longMetric, leadingBearingX);

    92 };

    93 

    94 struct hmtx : _mtx {

    95   static const hb_tag_t tableTag        = HB_OT_TAG_hmtx;

    96 };

    97 struct vmtx : _mtx {

    98   static const hb_tag_t tableTag        = HB_OT_TAG_vmtx;

    99 };

   100 

   101 } /* namespace OT */

   102 

   103 

   104 #endif /* HB_OT_HMTX_TABLE_HH */