1/*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.  Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26
27/*
28 *
29 * (C) Copyright IBM Corp. 1998-2010 - All Rights Reserved
30 *
31 */
32
33#include "LETypes.h"
34#include "LayoutEngine.h"
35#include "ThaiLayoutEngine.h"
36#include "ScriptAndLanguageTags.h"
37#include "LEGlyphStorage.h"
38
39#include "KernTable.h"
40
41#include "ThaiShaping.h"
42
43U_NAMESPACE_BEGIN
44
45UOBJECT_DEFINE_RTTI_IMPLEMENTATION(ThaiLayoutEngine)
46
47ThaiLayoutEngine::ThaiLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags, LEErrorCode &success)
48    : LayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, success)
49{
50    fErrorChar = 0x25CC;
51
52    // Figure out which presentation forms the font uses
53    if (! fontInstance->canDisplay(0x0E01)) {
54        // No Thai in font; don't use presentation forms.
55        fGlyphSet = 3;
56    } else if (fontInstance->canDisplay(0x0E64)) {
57        // WorldType uses reserved space in Thai block
58        fGlyphSet = 0;
59    } else if (fontInstance->canDisplay(0xF701)) {
60        // Microsoft corporate zone
61        fGlyphSet = 1;
62
63        if (!fontInstance->canDisplay(fErrorChar)) {
64            fErrorChar = 0xF71B;
65        }
66    } else if (fontInstance->canDisplay(0xF885)) {
67        // Apple corporate zone
68        fGlyphSet = 2;
69    } else {
70        // no presentation forms in the font
71        fGlyphSet = 3;
72    }
73}
74
75ThaiLayoutEngine::~ThaiLayoutEngine()
76{
77    // nothing to do
78}
79
80// Input: characters (0..max provided for context)
81// Output: glyphs, char indices
82// Returns: the glyph count
83// NOTE: this assumes that ThaiShaping::compose will allocate the outChars array...
84le_int32 ThaiLayoutEngine::computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool /*rightToLeft*/, LEGlyphStorage &glyphStorage, LEErrorCode &success)
85{
86    if (LE_FAILURE(success)) {
87        return 0;
88    }
89
90    if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
91        success = LE_ILLEGAL_ARGUMENT_ERROR;
92        return 0;
93    }
94
95    LEUnicode *outChars;
96    le_int32 glyphCount;
97
98    // This is enough room for the worst-case expansion
99    // (it says here...)
100    outChars = LE_NEW_ARRAY(LEUnicode, count * 2);
101
102    if (outChars == NULL) {
103        success = LE_MEMORY_ALLOCATION_ERROR;
104        return 0;
105    }
106
107    glyphStorage.allocateGlyphArray(count * 2, FALSE, success);
108
109    if (LE_FAILURE(success)) {
110        LE_DELETE_ARRAY(outChars);
111        success = LE_MEMORY_ALLOCATION_ERROR;
112        return 0;
113    }
114
115    glyphCount = ThaiShaping::compose(chars, offset, count, fGlyphSet, fErrorChar, outChars, glyphStorage);
116    mapCharsToGlyphs(outChars, 0, glyphCount, FALSE, FALSE, glyphStorage, success);
117
118    LE_DELETE_ARRAY(outChars);
119
120    glyphStorage.adoptGlyphCount(glyphCount);
121    return glyphCount;
122}
123
124// This is the same as LayoutEngline::adjustGlyphPositions() except that it doesn't call adjustMarkGlyphs
125void ThaiLayoutEngine::adjustGlyphPositions(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool  /*reverse*/,
126                                        LEGlyphStorage &glyphStorage, LEErrorCode &success)
127{
128    if (LE_FAILURE(success)) {
129        return;
130    }
131
132    if (chars == NULL || offset < 0 || count < 0) {
133        success = LE_ILLEGAL_ARGUMENT_ERROR;
134        return;
135    }
136
137    if (fTypoFlags & LE_Kerning_FEATURE_FLAG) { /* kerning enabled */
138      LETableReference kernTable(fFontInstance, LE_KERN_TABLE_TAG, success);
139      KernTable kt(kernTable, success);
140      kt.process(glyphStorage, success);
141    }
142
143    // default is no adjustments
144    return;
145}
146
147U_NAMESPACE_END
148