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39
40#ifndef QGLGRADIENTCACHE_P_H
41#define QGLGRADIENTCACHE_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 purely as an
48// implementation detail. 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 <QMultiHash>
55#include <QObject>
56#include <QtOpenGL/QtOpenGL>
57#include <private/qgl_p.h>
58#include <QtCore/qmutex.h>
59
60QT_BEGIN_NAMESPACE
61
62class QGL2GradientCache : public QOpenGLSharedResource
63{
64 struct CacheInfo
65 {
66 inline CacheInfo(QGradientStops s, qreal op, QGradient::InterpolationMode mode) :
67 stops(s), opacity(op), interpolationMode(mode) {}
68
69 GLuint texId;
70 QGradientStops stops;
71 qreal opacity;
72 QGradient::InterpolationMode interpolationMode;
73 };
74
75 typedef QMultiHash<quint64, CacheInfo> QGLGradientColorTableHash;
76
77public:
78 static QGL2GradientCache *cacheForContext(const QGLContext *context);
79
80 QGL2GradientCache(QOpenGLContext *);
81 ~QGL2GradientCache();
82
83 GLuint getBuffer(const QGradient &gradient, qreal opacity);
84 inline int paletteSize() const { return 1024; }
85
86 void invalidateResource() override;
87 void freeResource(QOpenGLContext *ctx) override;
88
89private:
90 inline int maxCacheSize() const { return 60; }
91 inline void generateGradientColorTable(const QGradient& gradient,
92 uint *colorTable,
93 int size, qreal opacity) const;
94 GLuint addCacheElement(quint64 hash_val, const QGradient &gradient, qreal opacity);
95 void cleanCache();
96
97 QGLGradientColorTableHash cache;
98 QMutex m_mutex;
99};
100
101QT_END_NAMESPACE
102
103#endif // QGLGRADIENTCACHE_P_H
104

source code of qtbase/src/opengl/gl2paintengineex/qglgradientcache_p.h