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39
40#ifndef QTEXTUREGLYPHCACHE_P_H
41#define QTEXTUREGLYPHCACHE_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists for the convenience
48// of other Qt classes. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtGui/private/qtguiglobal_p.h>
55#include <qhash.h>
56#include <qimage.h>
57#include <qobject.h>
58#include <qtransform.h>
59
60#include <private/qfontengineglyphcache_p.h>
61
62#ifndef QT_DEFAULT_TEXTURE_GLYPH_CACHE_WIDTH
63#define QT_DEFAULT_TEXTURE_GLYPH_CACHE_WIDTH 256
64#endif
65
66struct glyph_metrics_t;
67typedef unsigned int glyph_t;
68
69
70QT_BEGIN_NAMESPACE
71
72class QTextItemInt;
73
74class Q_GUI_EXPORT QTextureGlyphCache : public QFontEngineGlyphCache
75{
76public:
77 QTextureGlyphCache(QFontEngine::GlyphFormat format, const QTransform &matrix, const QColor &color = QColor())
78 : QFontEngineGlyphCache(format, matrix, color), m_current_fontengine(nullptr),
79 m_w(0), m_h(0), m_cx(0), m_cy(0), m_currentRowHeight(0)
80 { }
81
82 ~QTextureGlyphCache();
83
84 struct GlyphAndSubPixelPosition
85 {
86 GlyphAndSubPixelPosition(glyph_t g, QFixed spp) : glyph(g), subPixelPosition(spp) {}
87
88 bool operator==(const GlyphAndSubPixelPosition &other) const
89 {
90 return glyph == other.glyph && subPixelPosition == other.subPixelPosition;
91 }
92
93 glyph_t glyph;
94 QFixed subPixelPosition;
95 };
96
97 struct Coord {
98 int x;
99 int y;
100 int w;
101 int h;
102
103 int baseLineX;
104 int baseLineY;
105
106 bool isNull() const
107 {
108 return w == 0 || h == 0;
109 }
110 };
111
112 bool populate(QFontEngine *fontEngine, int numGlyphs, const glyph_t *glyphs,
113 const QFixedPoint *positions);
114 bool hasPendingGlyphs() const { return !m_pendingGlyphs.isEmpty(); };
115 void fillInPendingGlyphs();
116
117 virtual void createTextureData(int width, int height) = 0;
118 virtual void resizeTextureData(int width, int height) = 0;
119 virtual int glyphPadding() const { return 0; }
120
121 virtual void beginFillTexture() { }
122 virtual void fillTexture(const Coord &coord, glyph_t glyph, QFixed subPixelPosition) = 0;
123 virtual void endFillTexture() { }
124
125 inline void createCache(int width, int height) {
126 m_w = width;
127 m_h = height;
128 createTextureData(width, height);
129 }
130
131 inline void resizeCache(int width, int height)
132 {
133 resizeTextureData(width, height);
134 m_w = width;
135 m_h = height;
136 }
137
138 inline bool isNull() const { return m_h == 0; }
139
140 QHash<GlyphAndSubPixelPosition, Coord> coords;
141 virtual int maxTextureWidth() const { return QT_DEFAULT_TEXTURE_GLYPH_CACHE_WIDTH; }
142 virtual int maxTextureHeight() const { return -1; }
143
144 QImage textureMapForGlyph(glyph_t g, QFixed subPixelPosition) const;
145
146protected:
147 int calculateSubPixelPositionCount(glyph_t) const;
148
149 QFontEngine *m_current_fontengine;
150 QHash<GlyphAndSubPixelPosition, Coord> m_pendingGlyphs;
151
152 int m_w; // image width
153 int m_h; // image height
154 int m_cx; // current x
155 int m_cy; // current y
156 int m_currentRowHeight; // Height of last row
157};
158
159inline uint qHash(const QTextureGlyphCache::GlyphAndSubPixelPosition &g)
160{
161 return (g.glyph << 8) | (g.subPixelPosition * 10).round().toInt();
162}
163
164
165class Q_GUI_EXPORT QImageTextureGlyphCache : public QTextureGlyphCache
166{
167public:
168 QImageTextureGlyphCache(QFontEngine::GlyphFormat format, const QTransform &matrix, const QColor &color = QColor())
169 : QTextureGlyphCache(format, matrix, color) { }
170 ~QImageTextureGlyphCache();
171
172 virtual void createTextureData(int width, int height) override;
173 virtual void resizeTextureData(int width, int height) override;
174 virtual void fillTexture(const Coord &c, glyph_t glyph, QFixed subPixelPosition) override;
175
176 inline const QImage &image() const { return m_image; }
177
178private:
179 QImage m_image;
180};
181
182QT_END_NAMESPACE
183
184#endif
185

source code of qtbase/src/gui/painting/qtextureglyphcache_p.h