1/*
2 * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
3 * (C) 2000 Antti Koivisto (koivisto@kde.org)
4 * (C) 2000 Dirk Mueller (mueller@kde.org)
5 * Copyright (C) 2003-2018 Apple Inc. All rights reserved.
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public License
18 * along with this library; see the file COPYING.LIB. If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
21 *
22 */
23
24#ifndef TextRun_h
25#define TextRun_h
26
27#include "TextFlags.h"
28#include "WritingMode.h"
29#include <wtf/text/StringView.h>
30
31namespace WebCore {
32
33class FloatPoint;
34class FloatRect;
35class FontCascade;
36class GraphicsContext;
37class GlyphBuffer;
38class Font;
39
40struct GlyphData;
41struct WidthIterator;
42
43class TextRun {
44 WTF_MAKE_FAST_ALLOCATED;
45public:
46 explicit TextRun(const String& text, float xpos = 0, float expansion = 0, ExpansionBehavior expansionBehavior = DefaultExpansion, TextDirection direction = TextDirection::LTR, bool directionalOverride = false, bool characterScanForCodePath = true)
47 : m_text(text)
48 , m_tabSize(0)
49 , m_xpos(xpos)
50 , m_horizontalGlyphStretch(1)
51 , m_expansion(expansion)
52 , m_expansionBehavior(expansionBehavior)
53 , m_allowTabs(false)
54 , m_direction(static_cast<unsigned>(direction))
55 , m_directionalOverride(directionalOverride)
56 , m_characterScanForCodePath(characterScanForCodePath)
57 , m_disableSpacing(false)
58 {
59 ASSERT(!m_text.isNull());
60 }
61
62 explicit TextRun(StringView stringView, float xpos = 0, float expansion = 0, ExpansionBehavior expansionBehavior = DefaultExpansion, TextDirection direction = TextDirection::LTR, bool directionalOverride = false, bool characterScanForCodePath = true)
63 : TextRun(stringView.toStringWithoutCopying(), xpos, expansion, expansionBehavior, direction, directionalOverride, characterScanForCodePath)
64 {
65 }
66
67 TextRun subRun(unsigned startOffset, unsigned length) const
68 {
69 ASSERT_WITH_SECURITY_IMPLICATION(startOffset < m_text.length());
70
71 auto result { *this };
72
73 if (is8Bit())
74 result.setText(data8(startOffset), length);
75 else
76 result.setText(data16(startOffset), length);
77 return result;
78 }
79
80 UChar operator[](unsigned i) const { ASSERT_WITH_SECURITY_IMPLICATION(i < m_text.length()); return m_text[i]; }
81 const LChar* data8(unsigned i) const { ASSERT_WITH_SECURITY_IMPLICATION(i < m_text.length()); ASSERT(is8Bit()); return &m_text.characters8()[i]; }
82 const UChar* data16(unsigned i) const { ASSERT_WITH_SECURITY_IMPLICATION(i < m_text.length()); ASSERT(!is8Bit()); return &m_text.characters16()[i]; }
83
84 const LChar* characters8() const { ASSERT(is8Bit()); return m_text.characters8(); }
85 const UChar* characters16() const { ASSERT(!is8Bit()); return m_text.characters16(); }
86
87 bool is8Bit() const { return m_text.is8Bit(); }
88 unsigned length() const { return m_text.length(); }
89
90 void setText(const LChar* text, unsigned length) { setText({ text, length }); }
91 void setText(const UChar* text, unsigned length) { setText({ text, length }); }
92 void setText(StringView text) { ASSERT(!text.isNull()); m_text = text.toStringWithoutCopying(); }
93
94 float horizontalGlyphStretch() const { return m_horizontalGlyphStretch; }
95 void setHorizontalGlyphStretch(float scale) { m_horizontalGlyphStretch = scale; }
96
97 bool allowTabs() const { return m_allowTabs; }
98 unsigned tabSize() const { return m_tabSize; }
99 void setTabSize(bool, unsigned);
100
101 float xPos() const { return m_xpos; }
102 void setXPos(float xPos) { m_xpos = xPos; }
103 float expansion() const { return m_expansion; }
104 ExpansionBehavior expansionBehavior() const { return m_expansionBehavior; }
105 TextDirection direction() const { return static_cast<TextDirection>(m_direction); }
106 bool rtl() const { return static_cast<TextDirection>(m_direction) == TextDirection::RTL; }
107 bool ltr() const { return static_cast<TextDirection>(m_direction) == TextDirection::LTR; }
108 bool directionalOverride() const { return m_directionalOverride; }
109 bool characterScanForCodePath() const { return m_characterScanForCodePath; }
110 bool spacingDisabled() const { return m_disableSpacing; }
111
112 void disableSpacing() { m_disableSpacing = true; }
113 void setDirection(TextDirection direction) { m_direction = static_cast<unsigned>(direction); }
114 void setDirectionalOverride(bool override) { m_directionalOverride = override; }
115 void setCharacterScanForCodePath(bool scan) { m_characterScanForCodePath = scan; }
116 StringView text() const { return m_text; }
117
118private:
119 String m_text;
120
121 unsigned m_tabSize;
122
123 // m_xpos is the x position relative to the left start of the text line, not relative to the left
124 // start of the containing block. In the case of right alignment or center alignment, left start of
125 // the text line is not the same as left start of the containing block. This variable is only used
126 // to calculate the width of \t
127 float m_xpos;
128 float m_horizontalGlyphStretch;
129
130 float m_expansion;
131 unsigned m_expansionBehavior : 4;
132 unsigned m_allowTabs : 1;
133 unsigned m_direction : 1;
134 unsigned m_directionalOverride : 1; // Was this direction set by an override character.
135 unsigned m_characterScanForCodePath : 1;
136 unsigned m_disableSpacing : 1;
137};
138
139inline void TextRun::setTabSize(bool allow, unsigned size)
140{
141 m_allowTabs = allow;
142 m_tabSize = size;
143}
144
145}
146
147#endif
148