ICU-8.11.4.tar.gz
[apple/icu.git] / icuSources / layout / IndicLayoutEngine.cpp
1
2 /*
3 *
4 * (C) Copyright IBM Corp. 1998-2005 - All Rights Reserved
5 *
6 */
7
8 #include "LETypes.h"
9 #include "LayoutEngine.h"
10 #include "OpenTypeLayoutEngine.h"
11 #include "IndicLayoutEngine.h"
12 #include "ScriptAndLanguageTags.h"
13
14 #include "GlyphSubstitutionTables.h"
15 #include "GlyphDefinitionTables.h"
16 #include "GlyphPositioningTables.h"
17
18 #include "GDEFMarkFilter.h"
19 #include "LEGlyphStorage.h"
20
21 #include "IndicReordering.h"
22
23 U_NAMESPACE_BEGIN
24
25 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(IndicOpenTypeLayoutEngine)
26
27 IndicOpenTypeLayoutEngine::IndicOpenTypeLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode,
28 le_int32 typoFlags, const GlyphSubstitutionTableHeader *gsubTable)
29 : OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable), fMPreFixups(NULL)
30 {
31 fFeatureMap = IndicReordering::getFeatureMap(fFeatureMapCount);
32 fFeatureOrder = TRUE;
33
34 fFilterZeroWidth = IndicReordering::getFilterZeroWidth(fScriptCode);
35 }
36
37 IndicOpenTypeLayoutEngine::IndicOpenTypeLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags)
38 : OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags), fMPreFixups(NULL)
39 {
40 fFeatureMap = IndicReordering::getFeatureMap(fFeatureMapCount);
41 fFeatureOrder = TRUE;
42 }
43
44 IndicOpenTypeLayoutEngine::~IndicOpenTypeLayoutEngine()
45 {
46 // nothing to do
47 }
48
49 // Input: characters, tags
50 // Output: glyphs, char indices
51 le_int32 IndicOpenTypeLayoutEngine::glyphProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
52 LEGlyphStorage &glyphStorage, LEErrorCode &success)
53 {
54 if (LE_FAILURE(success)) {
55 return 0;
56 }
57
58 if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
59 success = LE_ILLEGAL_ARGUMENT_ERROR;
60 return 0;
61 }
62
63 le_int32 retCount = OpenTypeLayoutEngine::glyphProcessing(chars, offset, count, max, rightToLeft, glyphStorage, success);
64
65 if (LE_FAILURE(success)) {
66 return 0;
67 }
68
69 IndicReordering::adjustMPres(fMPreFixups, glyphStorage);
70
71 return retCount;
72 }
73
74 // Input: characters
75 // Output: characters, char indices, tags
76 // Returns: output character count
77 le_int32 IndicOpenTypeLayoutEngine::characterProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
78 LEUnicode *&outChars, LEGlyphStorage &glyphStorage, LEErrorCode &success)
79 {
80 if (LE_FAILURE(success)) {
81 return 0;
82 }
83
84 if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
85 success = LE_ILLEGAL_ARGUMENT_ERROR;
86 return 0;
87 }
88
89 le_int32 worstCase = count * IndicReordering::getWorstCaseExpansion(fScriptCode);
90
91 outChars = LE_NEW_ARRAY(LEUnicode, worstCase);
92
93 if (outChars == NULL) {
94 success = LE_MEMORY_ALLOCATION_ERROR;
95 return 0;
96 }
97
98 glyphStorage.allocateGlyphArray(worstCase, rightToLeft, success);
99 glyphStorage.allocateAuxData(success);
100
101 if (LE_FAILURE(success)) {
102 LE_DELETE_ARRAY(outChars);
103 return 0;
104 }
105
106 // NOTE: assumes this allocates featureTags...
107 // (probably better than doing the worst case stuff here...)
108 le_int32 outCharCount = IndicReordering::reorder(&chars[offset], count, fScriptCode, outChars, glyphStorage, &fMPreFixups);
109
110 glyphStorage.adoptGlyphCount(outCharCount);
111 return outCharCount;
112 }
113
114 U_NAMESPACE_END