Symaptic: os/textandloc/fontservices/textshaperplugin/IcuSource/layout/ArabicShaping.cpp@260cb5ec6c19

     1 /*

     2  *

     3  * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved

     4  *

     5  */

     7 #include "LETypes.h"

     8 #include "OpenTypeTables.h"

     9 #include "ArabicShaping.h"

    10 #include "LEGlyphStorage.h"

    12 U_NAMESPACE_BEGIN

    14 enum {

    15     _c_ = ArabicShaping::ST_NOSHAPE_DUAL,

    16     _d_ = ArabicShaping::ST_DUAL,

    17     _n_ = ArabicShaping::ST_NONE,

    18     _r_ = ArabicShaping::ST_RIGHT,

    19     _t_ = ArabicShaping::ST_TRANSPARENT,

    20     _x_ = ArabicShaping::ST_NOSHAPE_NONE

    21 };

    23 const ArabicShaping::ShapeType ArabicShaping::shapeTypes[] =

    24 {

    25     _t_, _t_, _t_, _t_, _t_, _t_, _x_, _x_, _x_, _x_, _x_, _n_, _x_, _x_, _x_, _n_,   // 0x610 - 0x61f

    26     _x_, _n_, _r_, _r_, _r_, _r_, _d_, _r_, _d_, _r_, _d_, _d_, _d_, _d_, _d_, _r_,   // 0x620 - 0x62f

    27     _r_, _r_, _r_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _x_, _x_, _x_, _x_, _x_,   // 0x630 - 0x63f

    28     _c_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _r_, _d_, _d_, _t_, _t_, _t_, _t_, _t_,   // 0x640 - 0x64f

    29     _t_, _t_, _t_, _t_, _t_, _t_, _t_, _t_, _t_, _x_, _x_, _x_, _x_, _x_, _x_, _x_,   // 0x650 - 0x65f

    30     _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _d_, _d_,   // 0x660 - 0x66f

    31     _t_, _r_, _r_, _r_, _n_, _r_, _r_, _r_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_,   // 0x670 - 0x67f

    32     _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _r_, _r_, _r_, _r_, _r_, _r_, _r_, _r_,   // 0x680 - 0x68f

    33     _r_, _r_, _r_, _r_, _r_, _r_, _r_, _r_, _r_, _r_, _d_, _d_, _d_, _d_, _d_, _d_,   // 0x690 - 0x69f

    34     _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_,   // 0x6a0 - 0x6af

    35     _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_, _d_,   // 0x6b0 - 0x6bf

    36     _r_, _d_, _r_, _r_, _r_, _r_, _r_, _r_, _r_, _r_, _r_, _r_, _d_, _r_, _d_, _r_,   // 0x6c0 - 0x6cf

    37     _d_, _d_, _r_, _r_, _n_, _r_, _t_, _t_, _t_, _t_, _t_, _t_, _t_, _x_, _t_, _t_,   // 0x6d0 - 0x6df

    38     _t_, _t_, _t_, _t_, _t_, _n_, _n_, _t_, _t_, _n_, _t_, _t_, _t_, _t_, _r_, _r_,   // 0x6e0 - 0x6ef

    39     _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _n_, _d_, _d_, _d_, _n_, _n_, _d_    // 0x6f0 - 0x6ff

    40 };

    42 /*

    43     shaping array holds types for Arabic chars between 0610 and 0700

    44     other values are either unshaped, or transparent if a mark or format

    45     code, except for format codes 200c (zero-width non-joiner) and 200d

    46     (dual-width joiner) which are both unshaped and non_joining or

    47     dual-joining, respectively.

    48 */

    49 ArabicShaping::ShapeType ArabicShaping::getShapeType(LEUnicode c)

    50 {

    51     if (c >= 0x0610 && c <= 0x206f) {

    52         if (c < 0x0700) {

    53             return shapeTypes[c - 0x0610];

    54         } else if (c == 0x200c) {   // ZWNJ

    55             return ST_NOSHAPE_NONE;

    56         } else if (c == 0x200d) {   // ZWJ

    57             return ST_NOSHAPE_DUAL;

    58         } else if (c >= 0x202a && c <= 0x202e) { // LRE - RLO

    59             return ST_TRANSPARENT;

    60         } else if (c >= 0x206a && c <= 0x206f) { // Inhibit Symmetric Swapping - Nominal Digit Shapes

    61             return ST_TRANSPARENT;

    62         }

    63     }

    65     return ST_NOSHAPE_NONE;

    66 }

    68 static const LETag isolFeatureTag = LE_ISOL_FEATURE_TAG;

    69 static const LETag initFeatureTag = LE_INIT_FEATURE_TAG;

    70 static const LETag mediFeatureTag = LE_MEDI_FEATURE_TAG;

    71 static const LETag finaFeatureTag = LE_FINA_FEATURE_TAG;

    72 static const LETag ligaFeatureTag = LE_LIGA_FEATURE_TAG;

    73 static const LETag msetFeatureTag = LE_MSET_FEATURE_TAG;

    74 static const LETag markFeatureTag = LE_MARK_FEATURE_TAG;

    75 static const LETag ccmpFeatureTag = LE_CCMP_FEATURE_TAG;

    76 static const LETag rligFeatureTag = LE_RLIG_FEATURE_TAG;

    77 static const LETag caltFeatureTag = LE_CALT_FEATURE_TAG;

    78 static const LETag dligFeatureTag = LE_DLIG_FEATURE_TAG;

    79 static const LETag cswhFeatureTag = LE_CSWH_FEATURE_TAG;

    80 static const LETag cursFeatureTag = LE_CURS_FEATURE_TAG;

    81 static const LETag kernFeatureTag = LE_KERN_FEATURE_TAG;

    82 static const LETag mkmkFeatureTag = LE_MKMK_FEATURE_TAG;

    84 static const LETag emptyTag       = 0x00000000; // ''

    86 static const LETag featureOrder[] =

    87 {

    88     ccmpFeatureTag, isolFeatureTag, finaFeatureTag, mediFeatureTag, initFeatureTag, rligFeatureTag,

    89     caltFeatureTag, ligaFeatureTag, dligFeatureTag, cswhFeatureTag, msetFeatureTag, cursFeatureTag,

    90     kernFeatureTag, markFeatureTag, mkmkFeatureTag, emptyTag

    91 };

    93 const LETag ArabicShaping::tagArray[] =

    94 {

    95     isolFeatureTag, ligaFeatureTag, msetFeatureTag, markFeatureTag, ccmpFeatureTag, rligFeatureTag,

    96         caltFeatureTag, dligFeatureTag, cswhFeatureTag, cursFeatureTag, kernFeatureTag, mkmkFeatureTag, emptyTag,

    98     finaFeatureTag, ligaFeatureTag, msetFeatureTag, markFeatureTag, ccmpFeatureTag, rligFeatureTag,

    99         caltFeatureTag, dligFeatureTag, cswhFeatureTag, cursFeatureTag, kernFeatureTag, mkmkFeatureTag, emptyTag,

   101     initFeatureTag, ligaFeatureTag, msetFeatureTag, markFeatureTag, ccmpFeatureTag, rligFeatureTag,

   102         caltFeatureTag, dligFeatureTag, cswhFeatureTag, cursFeatureTag, kernFeatureTag, mkmkFeatureTag, emptyTag,

   104     mediFeatureTag, ligaFeatureTag, msetFeatureTag, markFeatureTag, ccmpFeatureTag, rligFeatureTag,

   105         caltFeatureTag, dligFeatureTag, cswhFeatureTag, cursFeatureTag, kernFeatureTag, mkmkFeatureTag, emptyTag

   106 };

   108 #define TAGS_PER_GLYPH ((sizeof ArabicShaping::tagArray / sizeof ArabicShaping::tagArray[0]) / 4)

   110 const LETag *ArabicShaping::getFeatureOrder()

   111 {

   112     return featureOrder;

   113 }

   115 void ArabicShaping::adjustTags(le_int32 outIndex, le_int32 shapeOffset, LEGlyphStorage &glyphStorage)

   116 {

   117     LEErrorCode success = LE_NO_ERROR;

   118     const LETag *glyphTags = (const LETag *) glyphStorage.getAuxData(outIndex, success);

   120     glyphStorage.setAuxData(outIndex, (void *) &glyphTags[TAGS_PER_GLYPH * shapeOffset], success);

   121 }

   123 void ArabicShaping::shape(const LEUnicode *chars, le_int32 offset, le_int32 charCount, le_int32 charMax,

   124                           le_bool rightToLeft, LEGlyphStorage &glyphStorage)

   125 {

   126     // iterate in logical order, store tags in visible order

   127     //

   128     // the effective right char is the most recently encountered

   129     // non-transparent char

   130     //

   131     // four boolean states:

   132     //   the effective right char shapes

   133     //   the effective right char causes left shaping

   134     //   the current char shapes

   135     //   the current char causes right shaping

   136     //

   137     // if both cause shaping, then

   138     //   shaper.shape(errout, 2) (isolate to initial, or final to medial)

   139     //   shaper.shape(out, 1) (isolate to final)

   141     ShapeType rightType = ST_NOSHAPE_NONE, leftType = ST_NOSHAPE_NONE;

   142     LEErrorCode success = LE_NO_ERROR;

   143     le_int32 i;

   145     for (i = offset - 1; i >= 0; i -= 1) {

   146         rightType = getShapeType(chars[i]);

   148         if (rightType != ST_TRANSPARENT) {

   149             break;

   150         }

   151     }

   153     for (i = offset + charCount; i < charMax; i += 1) {

   154         leftType = getShapeType(chars[i]);

   156         if (leftType != ST_TRANSPARENT) {

   157             break;

   158         }

   159     }

   161     // erout is effective right logical index

   162     le_int32 erout = -1;

   163     le_bool rightShapes = FALSE;

   164     le_bool rightCauses = (rightType & MASK_SHAPE_LEFT) != 0;

   165     le_int32 in, e, out = 0, dir = 1;

   167     if (rightToLeft) {

   168         out = charCount - 1;

   169         erout = charCount;

   170         dir = -1;

   171     }

   173     for (in = offset, e = offset + charCount; in < e; in += 1, out += dir) {

   174         LEUnicode c = chars[in];

   175         ShapeType t = getShapeType(c);

   177         glyphStorage.setAuxData(out, (void *) tagArray, success);

   179         if ((t & MASK_TRANSPARENT) != 0) {

   180             continue;

   181         }

   183         le_bool curShapes = (t & MASK_NOSHAPE) == 0;

   184         le_bool curCauses = (t & MASK_SHAPE_RIGHT) != 0;

   186         if (rightCauses && curCauses) {

   187             if (rightShapes) {

   188                 adjustTags(erout, 2, glyphStorage);

   189             }

   191             if (curShapes) {

   192                 adjustTags(out, 1, glyphStorage);

   193             }

   194         }

   196         rightShapes = curShapes;

   197         rightCauses = (t & MASK_SHAPE_LEFT) != 0;

   198         erout = out;

   199     }

   201     if (rightShapes && rightCauses && (leftType & MASK_SHAPE_RIGHT) != 0) {

   202         adjustTags(erout, 2, glyphStorage);

   203     }

   204 }

   206 U_NAMESPACE_END

author	sl
	Tue, 10 Jun 2014 14:32:02 +0200
changeset 1	260cb5ec6c19
permissions	-rw-r--r--