Changeset 561 for trunk/src/gui/image/qpixmapcache.cpp

Timestamp:

Feb 11, 2010, 11:19:06 PM (15 years ago)

Author:

Dmitry A. Kuminov

Message:

trunk: Merged in qt 4.6.1 sources.

Location:

trunk

Files:

• . (modified) (1 prop)
• src/gui/image/qpixmapcache.cpp (modified) (20 diffs)

trunk/src/gui/image/qpixmapcache.cpp

@@ -2 +2 @@
 **
 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
-** Contact: Qt Software Information (qt-info@nokia.com)
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
 **
 ** This file is part of the QtGui module of the Qt Toolkit.
@@ -21 +22 @@
 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
 **
-** In addition, as a special exception, Nokia gives you certain
-** additional rights. These rights are described in the Nokia Qt LGPL
-** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
-** package.
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
 **
 ** GNU General Public License Usage
@@ -34 +34 @@
 ** met: http://www.gnu.org/copyleft/gpl.html.
 **
-** If you are unsure which license is appropriate for your use, please
-** contact the sales department at qt-sales@nokia.com.
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
 ** $QT_END_LICENSE$
 **
@@ -41 +41 @@
 
 #include "qpixmapcache.h"
-#include "qcache.h"
 #include "qobject.h"
 #include "qdebug.h"
-
-#include "qpaintengine.h"
-#include <private/qimage_p.h>
-#include <private/qpixmap_raster_p.h>
+#include "qpixmapcache_p.h"
 
 QT_BEGIN_NAMESPACE
@@ -56 +52 @@
     \brief The QPixmapCache class provides an application-wide cache for pixmaps.
 
-    \ingroup environment
-    \ingroup multimedia
+    \ingroup painting
 
     This class is a tool for optimized drawing with QPixmap. You can
@@ -69 +64 @@
     object for caching the pixmaps.
 
-    The cache associates a pixmap with a string (key). If two pixmaps
-    are inserted into the cache using equal keys, then the last pixmap
-    will hide the first pixmap. The QHash and QCache classes do
-    exactly the same.
+    The cache associates a pixmap with a user-provided string as a key,
+    or with a QPixmapCache::Key that the cache generates.
+    Using QPixmapCache::Key for keys is faster than using strings. The string API is
+    very convenient for complex keys but the QPixmapCache::Key API will be very
+    efficient and convenient for a one-to-one object-to-pixmap mapping \mdash in
+    this case, you can store the keys as members of an object.
+
+    If two pixmaps are inserted into the cache using equal keys then the
+    last pixmap will replace the first pixmap in the cache. This follows the
+    behavior of the QHash and QCache classes.
 
     The cache becomes full when the total size of all pixmaps in the
-    cache exceeds cacheLimit(). The initial cache limit is 1024 KB (1
-    MB); it is changed with setCacheLimit(). A pixmap takes roughly
-    (\e{width} * \e{height} * \e{depth})/8 bytes of memory.
+    cache exceeds cacheLimit(). The initial cache limit is
+    2048 KB (2 MB) on embedded platforms, 10240 KB (10 MB) on desktop
+    platforms; you can change this by calling setCacheLimit() with the
+    required value.
+    A pixmap takes roughly (\e{width} * \e{height} * \e{depth})/8 bytes of
+    memory.
 
     The \e{Qt Quarterly} article
-    \l{http://doc.trolltech.com/qq/qq12-qpixmapcache.html}{Optimizing
+    \l{http://qt.nokia.com/doc/qq/qq12-qpixmapcache.html}{Optimizing
     with QPixmapCache} explains how to use QPixmapCache to speed up
     applications by caching the results of painting.
@@ -87 +91 @@
 */
 
-#if defined(Q_WS_QWS) || defined(Q_OS_WINCE)
+#if defined(Q_OS_SYMBIAN)
+static int cache_limit = 1024; // 1048 KB cache limit for symbian
+#elif defined(Q_WS_QWS) || defined(Q_WS_WINCE)
 static int cache_limit = 2048; // 2048 KB cache limit for embedded
 #else
@@ -93 +99 @@
 #endif
 
-// XXX: hw: is this a general concept we need to abstract?
-class QDetachedPixmap : public QPixmap
-{
-public:
-    QDetachedPixmap(const QPixmap &pix) : QPixmap(pix)
-    {
-        if (data && data->classId() == QPixmapData::RasterClass) {
-            QRasterPixmapData *d = static_cast<QRasterPixmapData*>(data);
-            if (!d->image.isNull() && d->image.d->paintEngine
-                && !d->image.d->paintEngine->isActive())
-            {
-                delete d->image.d->paintEngine;
-                d->image.d->paintEngine = 0;
-            }
-        }
-    }
-};
-
-class QPMCache : public QObject, public QCache<qint64, QDetachedPixmap>
+/*!
+    \class QPixmapCache::Key
+    \brief The QPixmapCache::Key class can be used for efficient access
+    to the QPixmapCache.
+    \since 4.6
+
+    Use QPixmapCache::insert() to receive an instance of Key generated
+    by the pixmap cache. You can store the key in your own objects for
+    a very efficient one-to-one object-to-pixmap mapping.
+*/
+
+/*!
+    Constructs an empty Key object.
+*/
+QPixmapCache::Key::Key() : d(0)
+{
+}
+
+/*!
+   \internal
+    Constructs a copy of \a other.
+*/
+QPixmapCache::Key::Key(const Key &other)
+{
+    if (other.d)
+        ++(other.d->ref);
+    d = other.d;
+}
+
+/*!
+    Destroys the key.
+*/
+QPixmapCache::Key::~Key()
+{
+    if (d && --(d->ref) == 0)
+        delete d;
+}
+
+/*!
+    \internal
+
+    Returns true if this key is the same as the given \a key; otherwise returns
+    false.
+*/
+bool QPixmapCache::Key::operator ==(const Key &key) const
+{
+    return (d == key.d);
+}
+
+/*!
+    \fn bool QPixmapCache::Key::operator !=(const Key &key) const
+    \internal
+*/
+
+/*!
+    \internal
+*/
+QPixmapCache::Key &QPixmapCache::Key::operator =(const Key &other)
+{
+    if (d != other.d) {
+        if (other.d)
+            ++(other.d->ref);
+        if (d && --(d->ref) == 0)
+            delete d;
+        d = other.d;
+    }
+    return *this;
+}
+
+class QPMCache : public QObject, public QCache<QPixmapCache::Key, QPixmapCacheEntry>
 {
     Q_OBJECT
 public:
-    QPMCache()
-        : QObject(0),
-          QCache<qint64, QDetachedPixmap>(cache_limit * 1024),
-          theid(0), ps(0), t(false) { }
-    ~QPMCache() { }
+    QPMCache();
+    ~QPMCache();
 
     void timerEvent(QTimerEvent *);
     bool insert(const QString& key, const QPixmap &pixmap, int cost);
+    QPixmapCache::Key insert(const QPixmap &pixmap, int cost);
+    bool replace(const QPixmapCache::Key &key, const QPixmap &pixmap, int cost);
     bool remove(const QString &key);
+    bool remove(const QPixmapCache::Key &key);
+
+    void resizeKeyArray(int size);
+    QPixmapCache::Key createKey();
+    void releaseKey(const QPixmapCache::Key &key);
+    void clear();
 
     QPixmap *object(const QString &key) const;
+    QPixmap *object(const QPixmapCache::Key &key) const;
+
+    static inline QPixmapCache::KeyData *get(const QPixmapCache::Key &key)
+    {return key.d;}
+
+    static QPixmapCache::KeyData* getKeyData(QPixmapCache::Key *key);
 
 private:
-    QHash<QString, qint64> cacheKeys;
+    int *keyArray;
     int theid;
     int ps;
+    int keyArraySize;
+    int freeKey;
+    QHash<QString, QPixmapCache::Key> cacheKeys;
     bool t;
 };
+
 QT_BEGIN_INCLUDE_NAMESPACE
 #include "qpixmapcache.moc"
 QT_END_INCLUDE_NAMESPACE
 
+uint qHash(const QPixmapCache::Key &k)
+{
+    return qHash(QPMCache::get(k)->key);
+}
+
+QPMCache::QPMCache()
+    : QObject(0),
+      QCache<QPixmapCache::Key, QPixmapCacheEntry>(cache_limit * 1024),
+      keyArray(0), theid(0), ps(0), keyArraySize(0), freeKey(0), t(false)
+{
+}
+QPMCache::~QPMCache()
+{
+    clear();
+    free(keyArray);
+}
+
 /*
-  This is supposed to cut the cache size down by about 80-90% in a
+  This is supposed to cut the cache size down by about 25% in a
   minute once the application becomes idle, to let any inserted pixmap
   remain in the cache for some time before it becomes a candidate for
@@ -147 +236 @@
   timer so Qt won't keep the CPU from going into sleep mode.
 */
-
 void QPMCache::timerEvent(QTimerEvent *)
 {
@@ -156 +244 @@
     ps = totalCost();
 
-    QHash<QString, qint64>::iterator it = cacheKeys.begin();
+    QHash<QString, QPixmapCache::Key>::iterator it = cacheKeys.begin();
     while (it != cacheKeys.end()) {
         if (!contains(it.value())) {
+            releaseKey(it.value());
             it = cacheKeys.erase(it);
         } else {
@@ -177 +266 @@
 QPixmap *QPMCache::object(const QString &key) const
 {
-    return QCache<qint64, QDetachedPixmap>::object(cacheKeys.value(key, -1));
-}
-
+    QPixmapCache::Key cacheKey = cacheKeys.value(key);
+    if (!cacheKey.d || !cacheKey.d->isValid) {
+        const_cast<QPMCache *>(this)->cacheKeys.remove(key);
+        return 0;
+    }
+    QPixmap *ptr = QCache<QPixmapCache::Key, QPixmapCacheEntry>::object(cacheKey);
+     //We didn't find the pixmap in the cache, the key is not valid anymore
+    if (!ptr) {
+        const_cast<QPMCache *>(this)->cacheKeys.remove(key);
+    }
+    return ptr;
+}
+
+QPixmap *QPMCache::object(const QPixmapCache::Key &key) const
+{
+    Q_ASSERT(key.d->isValid);
+    QPixmap *ptr = QCache<QPixmapCache::Key, QPixmapCacheEntry>::object(key);
+    //We didn't find the pixmap in the cache, the key is not valid anymore
+    if (!ptr)
+        const_cast<QPMCache *>(this)->releaseKey(key);
+    return ptr;
+}
 
 bool QPMCache::insert(const QString& key, const QPixmap &pixmap, int cost)
 {
-    qint64 cacheKey = pixmap.cacheKey();
-    if (QCache<qint64, QDetachedPixmap>::object(cacheKey)) {
-        cacheKeys.insert(key, cacheKey);
-        return true;
-    }
-    bool success = QCache<qint64, QDetachedPixmap>::insert(cacheKey, new QDetachedPixmap(pixmap), cost);
+    QPixmapCache::Key cacheKey;
+    QPixmapCache::Key oldCacheKey = cacheKeys.value(key);
+    //If for the same key we add already a pixmap we should delete it
+    if (oldCacheKey.d) {
+        QCache<QPixmapCache::Key, QPixmapCacheEntry>::remove(oldCacheKey);
+        cacheKeys.remove(key);
+    }
+
+    //we create a new key the old one has been removed
+    cacheKey = createKey();
+
+    bool success = QCache<QPixmapCache::Key, QPixmapCacheEntry>::insert(cacheKey, new QPixmapCacheEntry(cacheKey, pixmap), cost);
     if (success) {
         cacheKeys.insert(key, cacheKey);
@@ -195 +309 @@
             t = false;
         }
+    } else {
+        //Insertion failed we released the new allocated key
+        releaseKey(cacheKey);
     }
     return success;
 }
 
+QPixmapCache::Key QPMCache::insert(const QPixmap &pixmap, int cost)
+{
+    QPixmapCache::Key cacheKey = createKey();
+    bool success = QCache<QPixmapCache::Key, QPixmapCacheEntry>::insert(cacheKey, new QPixmapCacheEntry(cacheKey, pixmap), cost);
+    if (success) {
+        if (!theid) {
+            theid = startTimer(30000);
+            t = false;
+        }
+    } else {
+        //Insertion failed we released the key and return an invalid one
+        releaseKey(cacheKey);
+    }
+    return cacheKey;
+}
+
+bool QPMCache::replace(const QPixmapCache::Key &key, const QPixmap &pixmap, int cost)
+{
+    Q_ASSERT(key.d->isValid);
+    //If for the same key we had already an entry so we should delete the pixmap and use the new one
+    QCache<QPixmapCache::Key, QPixmapCacheEntry>::remove(key);
+
+    QPixmapCache::Key cacheKey = createKey();
+
+    bool success = QCache<QPixmapCache::Key, QPixmapCacheEntry>::insert(cacheKey, new QPixmapCacheEntry(cacheKey, pixmap), cost);
+    if (success) {
+        if(!theid) {
+            theid = startTimer(30000);
+            t = false;
+        }
+        const_cast<QPixmapCache::Key&>(key) = cacheKey;
+    } else {
+        //Insertion failed we released the key
+        releaseKey(cacheKey);
+    }
+    return success;
+}
+
 bool QPMCache::remove(const QString &key)
 {
-    qint64 cacheKey = cacheKeys.value(key, -1);
+    QPixmapCache::Key cacheKey = cacheKeys.value(key);
+    //The key was not in the cache
+    if (!cacheKey.d)
+        return false;
     cacheKeys.remove(key);
-    return QCache<qint64, QDetachedPixmap>::remove(cacheKey);
+    return QCache<QPixmapCache::Key, QPixmapCacheEntry>::remove(cacheKey);
+}
+
+bool QPMCache::remove(const QPixmapCache::Key &key)
+{
+    return QCache<QPixmapCache::Key, QPixmapCacheEntry>::remove(key);
+}
+
+void QPMCache::resizeKeyArray(int size)
+{
+    if (size <= keyArraySize || size == 0)
+        return;
+    keyArray = q_check_ptr(reinterpret_cast<int *>(realloc(keyArray,
+                    size * sizeof(int))));
+    for (int i = keyArraySize; i != size; ++i)
+        keyArray[i] = i + 1;
+    keyArraySize = size;
+}
+
+QPixmapCache::Key QPMCache::createKey()
+{
+    if (freeKey == keyArraySize)
+        resizeKeyArray(keyArraySize ? keyArraySize << 1 : 2);
+    int id = freeKey;
+    freeKey = keyArray[id];
+    QPixmapCache::Key key;
+    QPixmapCache::KeyData *d = QPMCache::getKeyData(&key);
+    d->key = ++id;
+    return key;
+}
+
+void QPMCache::releaseKey(const QPixmapCache::Key &key)
+{
+    if (key.d->key > keyArraySize || key.d->key <= 0)
+        return;
+    key.d->key--;
+    keyArray[key.d->key] = freeKey;
+    freeKey = key.d->key;
+    key.d->isValid = false;
+    key.d->key = 0;
+}
+
+void QPMCache::clear()
+{
+    free(keyArray);
+    keyArray = 0;
+    freeKey = 0;
+    keyArraySize = 0;
+    //Mark all keys as invalid
+    QList<QPixmapCache::Key> keys = QCache<QPixmapCache::Key, QPixmapCacheEntry>::keys();
+    for (int i = 0; i < keys.size(); ++i)
+        keys.at(i).d->isValid = false;
+    QCache<QPixmapCache::Key, QPixmapCacheEntry>::clear();
+}
+
+QPixmapCache::KeyData* QPMCache::getKeyData(QPixmapCache::Key *key)
+{
+    if (!key->d)
+        key->d = new QPixmapCache::KeyData;
+    return key->d;
 }
 
 Q_GLOBAL_STATIC(QPMCache, pm_cache)
 
-/*!
-  \obsolete
+int Q_AUTOTEST_EXPORT q_QPixmapCache_keyHashSize()
+{
+    return pm_cache()->size();
+}
+
+QPixmapCacheEntry::~QPixmapCacheEntry()
+{
+    pm_cache()->releaseKey(key);
+}
+
+/*!
+    \obsolete
     \overload
 
@@ -218 +445 @@
     fast). Subsequent insertions into the cache could cause the
     pointer to become invalid. For this reason, we recommend you use
-    find(const QString&, QPixmap&) instead.
+    bool find(const QString&, QPixmap*) instead.
 
     Example:
@@ -231 +458 @@
 
 /*!
-    Looks for a cached pixmap associated with the \a key in the cache.
-    If the pixmap is found, the function sets \a pm to that pixmap and
-    returns true; otherwise it leaves \a pm alone and returns false.
+    \obsolete
+
+    Use bool find(const QString&, QPixmap*) instead.
+*/
+
+bool QPixmapCache::find(const QString &key, QPixmap& pixmap)
+{
+    return find(key, &pixmap);
+}
+
+/*!
+    Looks for a cached pixmap associated with the given \a key in the cache.
+    If the pixmap is found, the function sets \a pixmap to that pixmap and
+    returns true; otherwise it leaves \a pixmap alone and returns false.
+
+    \since 4.6
 
     Example:
@@ -239 +479 @@
 */
 
-bool QPixmapCache::find(const QString &key, QPixmap& pm)
+bool QPixmapCache::find(const QString &key, QPixmap* pixmap)
 {
     QPixmap *ptr = pm_cache()->object(key);
-    if (ptr)
-        pm = *ptr;
+    if (ptr && pixmap)
+        *pixmap = *ptr;
     return ptr != 0;
 }
 
-
-/*!
-    Inserts a copy of the pixmap \a pm associated with the \a key into
+/*!
+    Looks for a cached pixmap associated with the given \a key in the cache.
+    If the pixmap is found, the function sets \a pixmap to that pixmap and
+    returns true; otherwise it leaves \a pixmap alone and returns false. If
+    the pixmap is not found, it means that the \a key is no longer valid,
+    so it will be released for the next insertion.
+
+    \since 4.6
+*/
+bool QPixmapCache::find(const Key &key, QPixmap* pixmap)
+{
+    //The key is not valid anymore, a flush happened before probably
+    if (!key.d || !key.d->isValid)
+        return false;
+    QPixmap *ptr = pm_cache()->object(key);
+    if (ptr && pixmap)
+        *pixmap = *ptr;
+    return ptr != 0;
+}
+
+/*!
+    Inserts a copy of the pixmap \a pixmap associated with the \a key into
     the cache.
 
@@ -268 +527 @@
 */
 
-bool QPixmapCache::insert(const QString &key, const QPixmap &pm)
-{
-    return pm_cache()->insert(key, pm, pm.width() * pm.height() * pm.depth() / 8);
+bool QPixmapCache::insert(const QString &key, const QPixmap &pixmap)
+{
+    return pm_cache()->insert(key, pixmap, pixmap.width() * pixmap.height() * pixmap.depth() / 8);
+}
+
+/*!
+    Inserts a copy of the given \a pixmap into the cache and returns a key
+    that can be used to retrieve it.
+
+    When a pixmap is inserted and the cache is about to exceed its
+    limit, it removes pixmaps until there is enough room for the
+    pixmap to be inserted.
+
+    The oldest pixmaps (least recently accessed in the cache) are
+    deleted when more space is needed.
+
+    \sa setCacheLimit(), replace()
+
+    \since 4.6
+*/
+QPixmapCache::Key QPixmapCache::insert(const QPixmap &pixmap)
+{
+    return pm_cache()->insert(pixmap, pixmap.width() * pixmap.height() * pixmap.depth() / 8);
+}
+
+/*!
+    Replaces the pixmap associated with the given \a key with the \a pixmap
+    specified. Returns true if the \a pixmap has been correctly inserted into
+    the cache; otherwise returns false.
+
+    \sa setCacheLimit(), insert()
+
+    \since 4.6
+*/
+bool QPixmapCache::replace(const Key &key, const QPixmap &pixmap)
+{
+    //The key is not valid anymore, a flush happened before probably
+    if (!key.d || !key.d->isValid)
+        return false;
+    return pm_cache()->replace(key, pixmap, pixmap.width() * pixmap.height() * pixmap.depth() / 8);
 }
 
@@ -276 +572 @@
     Returns the cache limit (in kilobytes).
 
-    The default cache limit is 2048 KB for Embedded, 10240 KB for Desktops.
+    The default cache limit is 2048 KB on embedded platforms, 10240 KB on
+    desktop platforms.
 
     \sa setCacheLimit()
@@ -289 +586 @@
     Sets the cache limit to \a n kilobytes.
 
-    The default setting is 1024 kilobytes.
+    The default setting is 2048 KB on embedded platforms, 10240 KB on
+    desktop platforms.
 
     \sa cacheLimit()
@@ -308 +606 @@
 }
 
+/*!
+  Removes the pixmap associated with \a key from the cache and releases
+  the key for a future insertion.
+
+  \since 4.6
+*/
+void QPixmapCache::remove(const Key &key)
+{
+    //The key is not valid anymore, a flush happened before probably
+    if (!key.d || !key.d->isValid)
+        return;
+    pm_cache()->remove(key);
+}
 
 /*!
@@ -315 +626 @@
 void QPixmapCache::clear()
 {
-    pm_cache()->clear();
+    QT_TRY {
+        pm_cache()->clear();
+    } QT_CATCH(const std::bad_alloc &) {
+        // if we ran out of memory during pm_cache(), it's no leak,
+        // so just ignore it.
+    }
 }