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 * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
29 *
30 */
31
32#ifndef __CHARSUBSTITUTIONFILTER_H
33#define __CHARSUBSTITUTIONFILTER_H
34
35#include "LETypes.h"
36#include "LEGlyphFilter.h"
37
38U_NAMESPACE_BEGIN
39
40class LEFontInstance;
41
42/**
43 * This filter is used by character-based GSUB processors. It
44 * accepts only those characters which the given font can display.
45 *
46 * Note: Implementation is in ArabicLayoutEngine.cpp
47 *
48 * @internal
49 */
50class CharSubstitutionFilter : public UMemory, public LEGlyphFilter
51{
52private:
53    /**
54     * Holds the font which is used to test the characters.
55     *
56     * @internal
57     */
58    const LEFontInstance *fFontInstance;
59
60    /**
61     * The copy constructor. Not allowed!
62     *
63     * @internal
64     */
65    CharSubstitutionFilter(const CharSubstitutionFilter &other); // forbid copying of this class
66
67    /**
68     * The replacement operator. Not allowed!
69     *
70     * @internal
71     */
72    CharSubstitutionFilter &operator=(const CharSubstitutionFilter &other); // forbid copying of this class
73
74public:
75    /**
76     * The constructor.
77     *
78     * @param fontInstance - the font to use to test the characters.
79     *
80     * @internal
81     */
82    CharSubstitutionFilter(const LEFontInstance *fontInstance);
83
84    /**
85     * The destructor.
86     *
87     * @internal
88     */
89    ~CharSubstitutionFilter();
90
91    /**
92     * This method is used to test if a particular
93     * character can be displayed by the filter's
94     * font.
95     *
96     * @param glyph - the Unicode character code to be tested
97     *
98     * @return TRUE if the filter's font can display this character.
99     *
100     * @internal
101     */
102    le_bool accept(LEGlyphID glyph, LEErrorCode &success) const;
103};
104
105U_NAMESPACE_END
106#endif
107