Add Qt3 development HEAD version

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diff --git a/src/kernel/qpixmapcache.cpp b/src/kernel/qpixmapcache.cpp
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+/****************************************************************************
+**
+** Implementation of QPixmapCache class
+**
+** Created : 950504
+**
+** Copyright (C) 1992-2008 Trolltech ASA.  All rights reserved.
+**
+** This file is part of the kernel module of the Qt GUI Toolkit.
+**
+** This file may be used under the terms of the GNU General
+** Public License versions 2.0 or 3.0 as published by the Free
+** Software Foundation and appearing in the files LICENSE.GPL2
+** and LICENSE.GPL3 included in the packaging of this file.
+** Alternatively you may (at your option) use any later version
+** of the GNU General Public License if such license has been
+** publicly approved by Trolltech ASA (or its successors, if any)
+** and the KDE Free Qt Foundation.
+**
+** Please review the following information to ensure GNU General
+** Public Licensing requirements will be met:
+** http://trolltech.com/products/qt/licenses/licensing/opensource/.
+** If you are unsure which license is appropriate for your use, please
+** review the following information:
+** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
+** or contact the sales department at sales@trolltech.com.
+**
+** This file may be used under the terms of the Q Public License as
+** defined by Trolltech ASA and appearing in the file LICENSE.QPL
+** included in the packaging of this file.  Licensees holding valid Qt
+** Commercial licenses may use this file in accordance with the Qt
+** Commercial License Agreement provided with the Software.
+**
+** This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
+** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted
+** herein.
+**
+**********************************************************************/
+
+#include "qpixmapcache.h"
+#include "qcache.h"
+#include "qobject.h"
+#include "qcleanuphandler.h"
+
+
+// REVISED: paul
+/*!
+    \class QPixmapCache qpixmapcache.h
+
+    \brief The QPixmapCache class provides an application-global cache for
+    pixmaps.
+
+    \ingroup environment
+    \ingroup graphics
+    \ingroup images
+
+    This class is a tool for optimized drawing with QPixmap. You can
+    use it to store temporary pixmaps that are expensive to generate
+    without using more storage space than cacheLimit(). Use insert()
+    to insert pixmaps, find() to find them and clear() to empty the
+    cache.
+
+    For example, QRadioButton has a non-trivial visual representation
+    so we don't want to regenerate a pixmap whenever a radio button is
+    displayed or changes state. In the function
+    QRadioButton::drawButton(), we do not draw the radio button
+    directly. Instead, we first check the global pixmap cache for a
+    pixmap with the key "$qt_radio_nnn_", where \c nnn is a numerical
+    value that specifies the the radio button state. If a pixmap is
+    found, we bitBlt() it onto the widget and return. Otherwise, we
+    create a new pixmap, draw the radio button in the pixmap, and
+    finally insert the pixmap in the global pixmap cache, using the
+    key above. The bitBlt() is ten times faster than drawing the
+    radio button. All radio buttons in the program share the cached
+    pixmap since QPixmapCache is application-global.
+
+    QPixmapCache contains no member data, only static functions to
+    access the global pixmap cache. It creates an internal QCache 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 QDict and QCache classes do
+    exactly the same.
+
+    The cache becomes full when the total size of all pixmaps in the
+    cache exceeds cacheLimit(). The initial cache limit is 1024 KByte
+    (1 MByte); it is changed with setCacheLimit(). A pixmap takes
+    roughly width*height*depth/8 bytes of memory.
+
+    See the \l QCache documentation for more details about the cache
+    mechanism.
+*/
+
+
+static const int cache_size = 149;		// size of internal hash array
+#ifdef Q_WS_MAC9
+static int cache_limit	  = 256;		// 256 KB cache limit
+#else
+static int cache_limit	  = 1024;		// 1024 KB cache limit
+#endif
+
+class QPMCache: public QObject, public QCache<QPixmap>
+{
+public:
+    QPMCache():
+	QObject( 0, "global pixmap cache" ),
+	QCache<QPixmap>( cache_limit * 1024, cache_size ),
+	id( 0 ), ps( 0 ), t( FALSE )
+	{
+	    setAutoDelete( TRUE );
+	}
+   ~QPMCache() {}
+    void timerEvent( QTimerEvent * );
+    bool insert( const QString& k, const QPixmap *d, int c, int p = 0 );
+private:
+    int id;
+    int ps;
+    bool t;
+};
+
+
+/*
+  This is supposed to cut the cache size down by about 80-90% 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
+  cleaning-up, and to not cut down the size of the cache while the
+  cache is in active use.
+
+  When the last pixmap has been deleted from the cache, kill the
+  timer so Qt won't keep the CPU from going into sleep mode.
+*/
+
+void QPMCache::timerEvent( QTimerEvent * )
+{
+    int mc = maxCost();
+    bool nt = totalCost() == ps;
+    setMaxCost( nt ? totalCost() * 3 / 4 : totalCost() -1 );
+    setMaxCost( mc );
+    ps = totalCost();
+
+    if ( !count() ) {
+	killTimer( id );
+	id = 0;
+    } else if ( nt != t ) {
+	killTimer( id );
+	id = startTimer( nt ? 10000 : 30000 );
+	t = nt;
+    }
+}
+
+bool QPMCache::insert( const QString& k, const QPixmap *d, int c, int p )
+{
+    bool r = QCache<QPixmap>::insert( k, d, c, p );
+    if ( r && !id ) {
+	id = startTimer( 30000 );
+	t = FALSE;
+    }
+    return r;
+}
+
+static QPMCache *pm_cache = 0;			// global pixmap cache
+
+static QSingleCleanupHandler<QPMCache> qpm_cleanup_cache;
+
+/*!
+    Returns the pixmap associated with the \a key in the cache, or
+    null if there is no such pixmap.
+
+    \warning If valid, you should copy the pixmap immediately (this is
+    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.
+
+    Example:
+    \code
+	QPixmap* pp;
+	QPixmap p;
+	if ( (pp=QPixmapCache::find("my_big_image", pm)) ) {
+	    p = *pp;
+	} else {
+	    p.load("bigimage.png");
+	    QPixmapCache::insert("my_big_image", new QPixmap(p));
+	}
+	painter->drawPixmap(0, 0, p);
+    \endcode
+*/
+
+QPixmap *QPixmapCache::find( const QString &key )
+{
+    return pm_cache ? pm_cache->find(key) : 0;
+}
+
+
+/*!
+    \overload
+
+    Looks for a cached pixmap associated with the \a key in the cache.
+    If a pixmap is found, the function sets \a pm to that pixmap and
+    returns TRUE; otherwise leaves \a pm alone and returns FALSE.
+
+    Example:
+    \code
+	QPixmap p;
+	if ( !QPixmapCache::find("my_big_image", pm) ) {
+	    pm.load("bigimage.png");
+	    QPixmapCache::insert("my_big_image", pm);
+	}
+	painter->drawPixmap(0, 0, p);
+    \endcode
+*/
+
+bool QPixmapCache::find( const QString &key, QPixmap& pm )
+{
+    QPixmap* p = pm_cache ? pm_cache->find(key) : 0;
+    if ( p ) pm = *p;
+    return !!p;
+}
+
+
+/*!
+  \obsolete
+  Inserts the pixmap \a pm associated with \a key into the cache.
+  Returns TRUE if successful, or FALSE if the pixmap is too big for the cache.
+
+  <strong>
+    Note: \a pm must be allocated on the heap (using \c new).
+
+    If this function returns FALSE, you must delete \a pm yourself.
+
+    If this function returns TRUE, do not use \a pm afterwards or
+    keep references to it because any other insertions into the cache,
+    whether from anywhere in the application or within Qt itself, could cause
+    the pixmap to be discarded from the cache and the pointer to
+    become invalid.
+
+    Due to these dangers, we strongly recommend that you use
+    insert(const QString&, const QPixmap&) instead.
+  </strong>
+*/
+
+bool QPixmapCache::insert( const QString &key, QPixmap *pm )
+{
+    if ( !pm_cache ) {				// create pixmap cache
+	pm_cache = new QPMCache;
+	Q_CHECK_PTR( pm_cache );
+	qpm_cleanup_cache.set( &pm_cache );
+    }
+    return pm_cache->insert( key, pm, pm->width()*pm->height()*pm->depth()/8 );
+}
+
+/*!
+    Inserts a copy of the pixmap \a pm associated with the \a key into
+    the cache.
+
+    All pixmaps inserted by the Qt library have a key starting with
+    "$qt", so your own pixmap keys should never begin "$qt".
+
+    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().
+*/
+
+bool QPixmapCache::insert( const QString &key, const QPixmap& pm )
+{
+    if ( !pm_cache ) {				// create pixmap cache
+	pm_cache = new QPMCache;
+	Q_CHECK_PTR( pm_cache );
+	qpm_cleanup_cache.set( &pm_cache );
+    }
+    QPixmap *p = new QPixmap(pm);
+    bool rt = pm_cache->insert( key, p, p->width()*p->height()*p->depth()/8 );
+    if ( !rt )
+	delete p;
+
+    return rt;
+}
+
+/*!
+    Returns the cache limit (in kilobytes).
+
+    The default setting is 1024 kilobytes.
+
+    \sa setCacheLimit().
+*/
+
+int QPixmapCache::cacheLimit()
+{
+    return cache_limit;
+}
+
+/*!
+    Sets the cache limit to \a n kilobytes.
+
+    The default setting is 1024 kilobytes.
+
+    \sa cacheLimit()
+*/
+
+void QPixmapCache::setCacheLimit( int n )
+{
+#ifdef Q_WS_MAC9
+    if(n > 256)
+        qWarning("QPixmapCache::setCacheLimit: Setting cache limits high is harmfull to mac9's health");
+#endif
+    cache_limit = n;
+    if ( pm_cache )
+	pm_cache->setMaxCost( 1024*cache_limit );
+}
+
+
+/*!
+  Removes the pixmap associated with \a key from the cache.
+*/
+void QPixmapCache::remove( const QString &key )
+{
+    if ( pm_cache )
+	pm_cache->remove( key );
+}
+
+
+/*!
+    Removes all pixmaps from the cache.
+*/
+
+void QPixmapCache::clear()
+{
+    if ( pm_cache )
+	pm_cache->clear();
+}