1 /****************************************************************************
2 **
3 ** Copyright (C) 2016 The Qt Company Ltd.
4 ** Contact: https://www.qt.io/licensing/
5 **
6 ** This file is part of the QtOpenGL module of the Qt Toolkit.
7 **
8 ** $QT_BEGIN_LICENSE:LGPL$
9 ** Commercial License Usage
10 ** Licensees holding valid commercial Qt licenses may use this file in
11 ** accordance with the commercial license agreement provided with the
12 ** Software or, alternatively, in accordance with the terms contained in
13 ** a written agreement between you and The Qt Company. For licensing terms
14 ** and conditions see https://www.qt.io/terms-conditions. For further
15 ** information use the contact form at https://www.qt.io/contact-us.
16 **
17 ** GNU Lesser General Public License Usage
18 ** Alternatively, this file may be used under the terms of the GNU Lesser
19 ** General Public License version 3 as published by the Free Software
20 ** Foundation and appearing in the file LICENSE.LGPL3 included in the
21 ** packaging of this file. Please review the following information to
22 ** ensure the GNU Lesser General Public License version 3 requirements
23 ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
24 **
25 ** GNU General Public License Usage
26 ** Alternatively, this file may be used under the terms of the GNU
27 ** General Public License version 2.0 or (at your option) the GNU General
28 ** Public license version 3 or any later version approved by the KDE Free
29 ** Qt Foundation. The licenses are as published by the Free Software
30 ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
31 ** included in the packaging of this file. Please review the following
32 ** information to ensure the GNU General Public License requirements will
33 ** be met: https://www.gnu.org/licenses/gpl-2.0.html and
34 ** https://www.gnu.org/licenses/gpl-3.0.html.
35 **
36 ** $QT_END_LICENSE$
37 **
38 ****************************************************************************/
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 
60 QT_BEGIN_NAMESPACE
61 
62 class QGL2GradientCache : public QOpenGLSharedResource
63 {
64     struct CacheInfo
65     {
CacheInfoCacheInfo66         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 
77 public:
78     static QGL2GradientCache *cacheForContext(const QGLContext *context);
79 
80     QGL2GradientCache(QOpenGLContext *);
81     ~QGL2GradientCache();
82 
83     GLuint getBuffer(const QGradient &gradient, qreal opacity);
paletteSize()84     inline int paletteSize() const { return 1024; }
85 
86     void invalidateResource() override;
87     void freeResource(QOpenGLContext *ctx) override;
88 
89 private:
maxCacheSize()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 
101 QT_END_NAMESPACE
102 
103 #endif // QGLGRADIENTCACHE_P_H
104