1 /*
2 *
3 * (C) Copyright IBM Corp. 1998-2013 - All Rights Reserved
4 *
5 */
6
7 #include "LETypes.h"
8 #include "OpenTypeTables.h"
9 #include "ArabicShaping.h"
10 #include "LEGlyphStorage.h"
11 #include "ClassDefinitionTables.h"
12
13 U_NAMESPACE_BEGIN
14
15 // This table maps Unicode joining types to
16 // ShapeTypes.
17 const ArabicShaping::ShapeType ArabicShaping::shapeTypes[] =
18 {
19 ArabicShaping::ST_NOSHAPE_NONE, // [U]
20 ArabicShaping::ST_NOSHAPE_DUAL, // [C]
21 ArabicShaping::ST_DUAL, // [D]
22 ArabicShaping::ST_LEFT, // [L]
23 ArabicShaping::ST_RIGHT, // [R]
24 ArabicShaping::ST_TRANSPARENT // [T]
25 };
26
27 /*
28 shaping array holds types for Arabic chars between 0610 and 0700
29 other values are either unshaped, or transparent if a mark or format
30 code, except for format codes 200c (zero-width non-joiner) and 200d
31 (dual-width joiner) which are both unshaped and non_joining or
32 dual-joining, respectively.
33 */
getShapeType(LEUnicode c)34 ArabicShaping::ShapeType ArabicShaping::getShapeType(LEUnicode c)
35 {
36 LEErrorCode success = LE_NO_ERROR;
37 const LEReferenceTo<ClassDefinitionTable> joiningTypes((const ClassDefinitionTable *) ArabicShaping::shapingTypeTable,
38 ArabicShaping::shapingTypeTableLen);
39 le_int32 joiningType = joiningTypes->getGlyphClass(joiningTypes, c, success);
40
41 if (joiningType >= 0 && joiningType < ArabicShaping::JT_COUNT && LE_SUCCESS(success)) {
42 return ArabicShaping::shapeTypes[joiningType];
43 }
44
45 return ArabicShaping::ST_NOSHAPE_NONE;
46 }
47
48 #define isolFeatureTag LE_ISOL_FEATURE_TAG
49 #define initFeatureTag LE_INIT_FEATURE_TAG
50 #define mediFeatureTag LE_MEDI_FEATURE_TAG
51 #define finaFeatureTag LE_FINA_FEATURE_TAG
52 #define ligaFeatureTag LE_LIGA_FEATURE_TAG
53 #define msetFeatureTag LE_MSET_FEATURE_TAG
54 #define markFeatureTag LE_MARK_FEATURE_TAG
55 #define ccmpFeatureTag LE_CCMP_FEATURE_TAG
56 #define rligFeatureTag LE_RLIG_FEATURE_TAG
57 #define caltFeatureTag LE_CALT_FEATURE_TAG
58 #define dligFeatureTag LE_DLIG_FEATURE_TAG
59 #define cswhFeatureTag LE_CSWH_FEATURE_TAG
60 #define cursFeatureTag LE_CURS_FEATURE_TAG
61 #define kernFeatureTag LE_KERN_FEATURE_TAG
62 #define mkmkFeatureTag LE_MKMK_FEATURE_TAG
63
64 // NOTE:
65 // The isol, fina, init and medi features must be
66 // defined in the above order, and have masks that
67 // are all in the same nibble.
68 #define isolFeatureMask 0x80000000UL
69 #define finaFeatureMask 0x40000000UL
70 #define initFeatureMask 0x20000000UL
71 #define mediFeatureMask 0x10000000UL
72 #define ccmpFeatureMask 0x08000000UL
73 #define rligFeatureMask 0x04000000UL
74 #define caltFeatureMask 0x02000000UL
75 #define ligaFeatureMask 0x01000000UL
76 #define dligFeatureMask 0x00800000UL
77 #define cswhFeatureMask 0x00400000UL
78 #define msetFeatureMask 0x00200000UL
79 #define cursFeatureMask 0x00100000UL
80 #define kernFeatureMask 0x00080000UL
81 #define markFeatureMask 0x00040000UL
82 #define mkmkFeatureMask 0x00020000UL
83
84 #define NO_FEATURES 0
85 #define ISOL_FEATURES (isolFeatureMask | ligaFeatureMask | msetFeatureMask | markFeatureMask | ccmpFeatureMask | rligFeatureMask | caltFeatureMask | dligFeatureMask | cswhFeatureMask | cursFeatureMask | kernFeatureMask | mkmkFeatureMask)
86
87 #define SHAPE_MASK 0xF0000000UL
88
89 static const FeatureMap featureMap[] = {
90 {ccmpFeatureTag, ccmpFeatureMask},
91 {isolFeatureTag, isolFeatureMask},
92 {finaFeatureTag, finaFeatureMask},
93 {mediFeatureTag, mediFeatureMask},
94 {initFeatureTag, initFeatureMask},
95 {rligFeatureTag, rligFeatureMask},
96 {caltFeatureTag, caltFeatureMask},
97 {ligaFeatureTag, ligaFeatureMask},
98 {dligFeatureTag, dligFeatureMask},
99 {cswhFeatureTag, cswhFeatureMask},
100 {msetFeatureTag, msetFeatureMask},
101 {cursFeatureTag, cursFeatureMask},
102 {kernFeatureTag, kernFeatureMask},
103 {markFeatureTag, markFeatureMask},
104 {mkmkFeatureTag, mkmkFeatureMask}
105 };
106
getFeatureMap(le_int32 & count)107 const FeatureMap *ArabicShaping::getFeatureMap(le_int32 &count)
108 {
109 count = LE_ARRAY_SIZE(featureMap);
110
111 return featureMap;
112 }
113
adjustTags(le_int32 outIndex,le_int32 shapeOffset,LEGlyphStorage & glyphStorage)114 void ArabicShaping::adjustTags(le_int32 outIndex, le_int32 shapeOffset, LEGlyphStorage &glyphStorage)
115 {
116 LEErrorCode success = LE_NO_ERROR;
117 FeatureMask featureMask = (FeatureMask) glyphStorage.getAuxData(outIndex, success);
118 FeatureMask shape = featureMask & SHAPE_MASK;
119
120 shape >>= shapeOffset;
121
122 glyphStorage.setAuxData(outIndex, ((featureMask & ~SHAPE_MASK) | shape), success);
123 }
124
shape(const LEUnicode * chars,le_int32 offset,le_int32 charCount,le_int32 charMax,le_bool rightToLeft,LEGlyphStorage & glyphStorage)125 void ArabicShaping::shape(const LEUnicode *chars, le_int32 offset, le_int32 charCount, le_int32 charMax,
126 le_bool rightToLeft, LEGlyphStorage &glyphStorage)
127 {
128 // iterate in logical order, store tags in visible order
129 //
130 // the effective right char is the most recently encountered
131 // non-transparent char
132 //
133 // four boolean states:
134 // the effective right char shapes
135 // the effective right char causes left shaping
136 // the current char shapes
137 // the current char causes right shaping
138 //
139 // if both cause shaping, then
140 // shaper.shape(errout, 2) (isolate to initial, or final to medial)
141 // shaper.shape(out, 1) (isolate to final)
142
143 ShapeType rightType = ST_NOSHAPE_NONE, leftType = ST_NOSHAPE_NONE;
144 LEErrorCode success = LE_NO_ERROR;
145 le_int32 i;
146
147 for (i = offset - 1; i >= 0; i -= 1) {
148 rightType = getShapeType(chars[i]);
149
150 if (rightType != ST_TRANSPARENT) {
151 break;
152 }
153 }
154
155 for (i = offset + charCount; i < charMax; i += 1) {
156 leftType = getShapeType(chars[i]);
157
158 if (leftType != ST_TRANSPARENT) {
159 break;
160 }
161 }
162
163 // erout is effective right logical index
164 le_int32 erout = -1;
165 le_bool rightShapes = FALSE;
166 le_bool rightCauses = (rightType & MASK_SHAPE_LEFT) != 0;
167 le_int32 in, e, out = 0, dir = 1;
168
169 if (rightToLeft) {
170 out = charCount - 1;
171 erout = charCount;
172 dir = -1;
173 }
174
175 for (in = offset, e = offset + charCount; in < e; in += 1, out += dir) {
176 LEUnicode c = chars[in];
177 ShapeType t = getShapeType(c);
178
179 if (t == ST_NOSHAPE_NONE) {
180 glyphStorage.setAuxData(out, NO_FEATURES, success);
181 } else {
182 glyphStorage.setAuxData(out, ISOL_FEATURES, success);
183 }
184
185 if ((t & MASK_TRANSPARENT) != 0) {
186 continue;
187 }
188
189 le_bool curShapes = (t & MASK_NOSHAPE) == 0;
190 le_bool curCauses = (t & MASK_SHAPE_RIGHT) != 0;
191
192 if (rightCauses && curCauses) {
193 if (rightShapes) {
194 adjustTags(erout, 2, glyphStorage);
195 }
196
197 if (curShapes) {
198 adjustTags(out, 1, glyphStorage);
199 }
200 }
201
202 rightShapes = curShapes;
203 rightCauses = (t & MASK_SHAPE_LEFT) != 0;
204 erout = out;
205 }
206
207 if (rightShapes && rightCauses && (leftType & MASK_SHAPE_RIGHT) != 0) {
208 adjustTags(erout, 2, glyphStorage);
209 }
210 }
211
212 U_NAMESPACE_END
213