src/hb-ot-shape-complex-indic-private.hh

   1 /*
   2  * Copyright © 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_SHAPE_COMPLEX_INDIC_PRIVATE_HH
  28 #define HB_OT_SHAPE_COMPLEX_INDIC_PRIVATE_HH
  29
  30 #include "hb-private.hh"
  31
  32
  33 #include "hb-ot-shape-complex-private.hh"
  34 #include "hb-ot-shape-private.hh" /* XXX Remove */
  35
  36
  37 #define INDIC_TABLE_ELEMENT_TYPE uint16_t
  38
  39 /* Cateories used in the OpenType spec:
  40  * https://www.microsoft.com/typography/otfntdev/devanot/shaping.aspx
  41  */
  42 /* Note: This enum is duplicated in the -machine.rl source file.
  43  * Not sure how to avoid duplication. */
  44 enum indic_category_t {
  45   OT_X = 0,
  46   OT_C = 1,
  47   OT_V = 2,
  48   OT_N = 3,
  49   OT_H = 4,
  50   OT_ZWNJ = 5,
  51   OT_ZWJ = 6,
  52   OT_M = 7,
  53   OT_SM = 8,
  54   OT_VD = 9,
  55   OT_A = 10,
  56   OT_PLACEHOLDER = 11,
  57   OT_DOTTEDCIRCLE = 12,
  58   OT_RS = 13, /* Register Shifter, used in Khmer OT spec. */
  59   OT_Coeng = 14, /* Khmer-style Virama. */
  60   OT_Repha = 15, /* Atomically-encoded logical or visual repha. */
  61   OT_Ra = 16,
  62   OT_CM = 17,  /* Consonant-Medial. */
  63   OT_Symbol = 18, /* Avagraha, etc that take marks (SM,A,VD). */
  64   OT_CM2 = 31 /* Consonant-Medial, second slot. */
  65 };
  66
  67 #define MEDIAL_FLAGS (FLAG (OT_CM) | FLAG (OT_CM2))
  68
  69 /* Note:
  70  *
  71  * We treat Vowels and placeholders as if they were consonants.  This is safe because Vowels
  72  * cannot happen in a consonant syllable.  The plus side however is, we can call the
  73  * consonant syllable logic from the vowel syllable function and get it all right! */
  74 #define CONSONANT_FLAGS (FLAG (OT_C) | FLAG (OT_Ra) | MEDIAL_FLAGS | FLAG (OT_V) | FLAG (OT_PLACEHOLDER) | FLAG (OT_DOTTEDCIRCLE))
  75 #define JOINER_FLAGS (FLAG (OT_ZWJ) | FLAG (OT_ZWNJ))
  76 #define HALANT_OR_COENG_FLAGS (FLAG (OT_H) | FLAG (OT_Coeng))
  77
  78
  79 /* Visual positions in a syllable from left to right. */
  80 enum indic_position_t {
  81   POS_START,
  82
  83   POS_RA_TO_BECOME_REPH,
  84   POS_PRE_M,
  85   POS_PRE_C,
  86
  87   POS_BASE_C,
  88   POS_AFTER_MAIN,
  89
  90   POS_ABOVE_C,
  91
  92   POS_BEFORE_SUB,
  93   POS_BELOW_C,
  94   POS_AFTER_SUB,
  95
  96   POS_BEFORE_POST,
  97   POS_POST_C,
  98   POS_AFTER_POST,
  99
 100   POS_FINAL_C,
 101   POS_SMVD,
 102
 103   POS_END
 104 };
 105
 106 /* Categories used in IndicSyllabicCategory.txt from UCD. */
 107 enum indic_syllabic_category_t {
 108   INDIC_SYLLABIC_CATEGORY_OTHER                         = OT_X,
 109
 110   INDIC_SYLLABIC_CATEGORY_AVAGRAHA                      = OT_Symbol,
 111   INDIC_SYLLABIC_CATEGORY_BINDU                         = OT_SM,
 112   INDIC_SYLLABIC_CATEGORY_BRAHMI_JOINING_NUMBER         = OT_PLACEHOLDER, /* TODO */
 113   INDIC_SYLLABIC_CATEGORY_CANTILLATION_MARK             = OT_A,
 114   INDIC_SYLLABIC_CATEGORY_CONSONANT                     = OT_C,
 115   INDIC_SYLLABIC_CATEGORY_CONSONANT_DEAD                = OT_C,
 116   INDIC_SYLLABIC_CATEGORY_CONSONANT_FINAL               = OT_CM,
 117   INDIC_SYLLABIC_CATEGORY_CONSONANT_HEAD_LETTER         = OT_C,
 118   INDIC_SYLLABIC_CATEGORY_CONSONANT_MEDIAL              = OT_CM,
 119   INDIC_SYLLABIC_CATEGORY_CONSONANT_PLACEHOLDER         = OT_PLACEHOLDER,
 120   INDIC_SYLLABIC_CATEGORY_CONSONANT_PRECEDING_REPHA     = OT_Repha,
 121   INDIC_SYLLABIC_CATEGORY_CONSONANT_SUBJOINED           = OT_CM,
 122   INDIC_SYLLABIC_CATEGORY_CONSONANT_SUCCEEDING_REPHA    = OT_N,
 123   INDIC_SYLLABIC_CATEGORY_GEMINATION_MARK               = OT_SM,
 124   INDIC_SYLLABIC_CATEGORY_INVISIBLE_STACKER             = OT_H, /* TODO */
 125   INDIC_SYLLABIC_CATEGORY_JOINER                        = OT_ZWJ,
 126   INDIC_SYLLABIC_CATEGORY_MODIFYING_LETTER              = OT_X,
 127   INDIC_SYLLABIC_CATEGORY_NON_JOINER                    = OT_ZWNJ,
 128   INDIC_SYLLABIC_CATEGORY_NUKTA                         = OT_N,
 129   INDIC_SYLLABIC_CATEGORY_NUMBER                        = OT_PLACEHOLDER,
 130   INDIC_SYLLABIC_CATEGORY_NUMBER_JOINER                 = OT_PLACEHOLDER, /* TODO */
 131   INDIC_SYLLABIC_CATEGORY_PURE_KILLER                   = OT_H, /* TODO */
 132   INDIC_SYLLABIC_CATEGORY_REGISTER_SHIFTER              = OT_RS,
 133   INDIC_SYLLABIC_CATEGORY_TONE_LETTER                   = OT_X,
 134   INDIC_SYLLABIC_CATEGORY_TONE_MARK                     = OT_N,
 135   INDIC_SYLLABIC_CATEGORY_VIRAMA                        = OT_H,
 136   INDIC_SYLLABIC_CATEGORY_VISARGA                       = OT_SM,
 137   INDIC_SYLLABIC_CATEGORY_VOWEL                         = OT_V,
 138   INDIC_SYLLABIC_CATEGORY_VOWEL_DEPENDENT               = OT_M,
 139   INDIC_SYLLABIC_CATEGORY_VOWEL_INDEPENDENT             = OT_V
 140 };
 141
 142 /* Categories used in IndicSMatraCategory.txt from UCD */
 143 enum indic_matra_category_t {
 144   INDIC_MATRA_CATEGORY_NOT_APPLICABLE                   = POS_END,
 145
 146   INDIC_MATRA_CATEGORY_LEFT                             = POS_PRE_C,
 147   INDIC_MATRA_CATEGORY_TOP                              = POS_ABOVE_C,
 148   INDIC_MATRA_CATEGORY_BOTTOM                           = POS_BELOW_C,
 149   INDIC_MATRA_CATEGORY_RIGHT                            = POS_POST_C,
 150
 151   /* These should resolve to the position of the last part of the split sequence. */
 152   INDIC_MATRA_CATEGORY_BOTTOM_AND_RIGHT                 = INDIC_MATRA_CATEGORY_RIGHT,
 153   INDIC_MATRA_CATEGORY_LEFT_AND_RIGHT                   = INDIC_MATRA_CATEGORY_RIGHT,
 154   INDIC_MATRA_CATEGORY_TOP_AND_BOTTOM                   = INDIC_MATRA_CATEGORY_BOTTOM,
 155   INDIC_MATRA_CATEGORY_TOP_AND_BOTTOM_AND_RIGHT         = INDIC_MATRA_CATEGORY_RIGHT,
 156   INDIC_MATRA_CATEGORY_TOP_AND_LEFT                     = INDIC_MATRA_CATEGORY_TOP,
 157   INDIC_MATRA_CATEGORY_TOP_AND_LEFT_AND_RIGHT           = INDIC_MATRA_CATEGORY_RIGHT,
 158   INDIC_MATRA_CATEGORY_TOP_AND_RIGHT                    = INDIC_MATRA_CATEGORY_RIGHT,
 159
 160   INDIC_MATRA_CATEGORY_OVERSTRUCK                       = POS_AFTER_MAIN,
 161   INDIC_MATRA_CATEGORY_VISUAL_ORDER_LEFT                = POS_PRE_M
 162 };
 163
 164 /* Note: We use ASSERT_STATIC_EXPR_ZERO() instead of ASSERT_STATIC_EXPR() and the comma operation
 165  * because gcc fails to optimize the latter and fills the table in at runtime. */
 166 #define INDIC_COMBINE_CATEGORIES(S,M) \
 167   (ASSERT_STATIC_EXPR_ZERO (M == INDIC_MATRA_CATEGORY_NOT_APPLICABLE || \
 168                             ( \
 169                              S == INDIC_SYLLABIC_CATEGORY_CONSONANT_MEDIAL || \
 170                              S == INDIC_SYLLABIC_CATEGORY_GEMINATION_MARK || \
 171                              S == INDIC_SYLLABIC_CATEGORY_REGISTER_SHIFTER || \
 172                              S == INDIC_SYLLABIC_CATEGORY_CONSONANT_SUCCEEDING_REPHA || \
 173                              S == INDIC_SYLLABIC_CATEGORY_VIRAMA || \
 174                              S == INDIC_SYLLABIC_CATEGORY_VOWEL_DEPENDENT || \
 175                              false)) + \
 176    ASSERT_STATIC_EXPR_ZERO (S < 255 && M < 255) + \
 177    ((M << 8) | S))
 178
 179 HB_INTERNAL INDIC_TABLE_ELEMENT_TYPE
 180 hb_indic_get_categories (hb_codepoint_t u);
 181
 182 #endif /* HB_OT_SHAPE_COMPLEX_INDIC_PRIVATE_HH */