1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
|
#include "cachingimagemanager.hpp"
#include <qobject.h>
#include <QtQuick/QQuickItem>
#include <QtQuick/QQuickWindow>
#include <QCryptographicHash>
#include <QThreadPool>
#include <QFile>
qreal CachingImageManager::effectiveScale() const {
if (m_item->window()) {
return m_item->window()->devicePixelRatio();
}
return 1.0;
}
int CachingImageManager::effectiveWidth() const {
int width = std::ceil(m_item->width() * effectiveScale());
m_item->setProperty("sourceWidth", width);
return width;
}
int CachingImageManager::effectiveHeight() const {
int height = std::ceil(m_item->height() * effectiveScale());
m_item->setProperty("sourceHeight", height);
return height;
}
QQuickItem* CachingImageManager::item() const {
return m_item;
}
void CachingImageManager::setItem(QQuickItem* item) {
if (m_item == item) {
return;
}
if (m_widthConn) {
disconnect(m_widthConn);
}
if (m_heightConn) {
disconnect(m_heightConn);
}
m_item = item;
emit itemChanged();
if (item) {
m_widthConn = connect(item, &QQuickItem::widthChanged, this, [this]() { updateSource(); });
m_heightConn = connect(item, &QQuickItem::heightChanged, this, [this]() { updateSource(); });
updateSource();
}
}
QUrl CachingImageManager::cacheDir() const {
return m_cacheDir;
}
void CachingImageManager::setCacheDir(const QUrl& cacheDir) {
if (m_cacheDir == cacheDir) {
return;
}
m_cacheDir = cacheDir;
if (!m_cacheDir.path().endsWith("/")) {
m_cacheDir.setPath(m_cacheDir.path() + "/");
}
emit cacheDirChanged();
}
QString CachingImageManager::path() const {
return m_path;
}
void CachingImageManager::setPath(const QString& path) {
if (m_path == path) {
return;
}
m_path = path;
emit pathChanged();
if (!path.isEmpty()) {
updateSource(path);
}
}
void CachingImageManager::updateSource() {
updateSource(m_path);
}
void CachingImageManager::updateSource(const QString& path) {
if (path.isEmpty()) {
return;
}
QThreadPool::globalInstance()->start([path, this] {
const QString sha = sha256sum(path);
QMetaObject::invokeMethod(this, [path, sha, this]() {
const QString filename = QString("%1@%2x%3.png")
.arg(sha)
.arg(effectiveWidth())
.arg(effectiveHeight());
const QUrl cache = m_cacheDir.resolved(QUrl(filename));
if (m_cachePath == cache) {
return;
}
m_cachePath = cache;
emit cachePathChanged();
if (!cache.isLocalFile()) {
qWarning() << "CachingImageManager::updateSource: cachePath" << cache << "is not a local file";
return;
}
bool cacheExists = QFile::exists(cache.toLocalFile());
if (cacheExists) {
m_item->setProperty("source", cache);
} else {
m_item->setProperty("source", QUrl::fromLocalFile(path));
}
m_usingCache = cacheExists;
emit usingCacheChanged();
}, Qt::QueuedConnection);
});
}
QUrl CachingImageManager::cachePath() const {
return m_cachePath;
}
bool CachingImageManager::usingCache() const {
return m_usingCache;
}
QString CachingImageManager::sha256sum(const QString& path) const {
QFile file(path);
if (!file.open(QIODevice::ReadOnly)) {
qWarning() << "CachingImageManager::sha256sum: failed to open" << path;
return "";
}
QCryptographicHash hash(QCryptographicHash::Sha256);
hash.addData(&file);
file.close();
return hash.result().toHex();
}
|
