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diff --git a/doc/html/ntqpixmapcache.html b/doc/html/ntqpixmapcache.html deleted file mode 100644 index c04710bcd..000000000 --- a/doc/html/ntqpixmapcache.html +++ /dev/null @@ -1,191 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> -<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/src/kernel/qpixmapcache.cpp:45 --> -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> -<title>TQPixmapCache Class</title> -<style type="text/css"><!-- -fn { margin-left: 1cm; text-indent: -1cm; } -a:link { color: #004faf; text-decoration: none } -a:visited { color: #672967; text-decoration: none } -body { background: #ffffff; color: black; } ---></style> -</head> -<body> - -<table border="0" cellpadding="0" cellspacing="0" width="100%"> -<tr bgcolor="#E5E5E5"> -<td valign=center> - <a href="index.html"> -<font color="#004faf">Home</font></a> - | <a href="classes.html"> -<font color="#004faf">All Classes</font></a> - | <a href="mainclasses.html"> -<font color="#004faf">Main Classes</font></a> - | <a href="annotated.html"> -<font color="#004faf">Annotated</font></a> - | <a href="groups.html"> -<font color="#004faf">Grouped Classes</font></a> - | <a href="functions.html"> -<font color="#004faf">Functions</font></a> -</td> -<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>TQPixmapCache Class Reference</h1> - -<p>The TQPixmapCache class provides an application-global cache for -pixmaps. -<a href="#details">More...</a> -<p><tt>#include <<a href="qpixmapcache-h.html">ntqpixmapcache.h</a>></tt> -<p><a href="qpixmapcache-members.html">List of all member functions.</a> -<h2>Static Public Members</h2> -<ul> -<li class=fn>int <a href="#cacheLimit"><b>cacheLimit</b></a> ()</li> -<li class=fn>void <a href="#setCacheLimit"><b>setCacheLimit</b></a> ( int n )</li> -<li class=fn>TQPixmap * <a href="#find"><b>find</b></a> ( const TQString & key )</li> -<li class=fn>bool <a href="#find-2"><b>find</b></a> ( const TQString & key, TQPixmap & pm )</li> -<li class=fn>bool insert ( const TQString & key, TQPixmap * pm ) <em>(obsolete)</em></li> -<li class=fn>bool <a href="#insert"><b>insert</b></a> ( const TQString & key, const TQPixmap & pm )</li> -<li class=fn>void <a href="#remove"><b>remove</b></a> ( const TQString & key )</li> -<li class=fn>void <a href="#clear"><b>clear</b></a> ()</li> -</ul> -<hr><a name="details"></a><h2>Detailed Description</h2> - - -<p> The TQPixmapCache class provides an application-global cache for -pixmaps. -<p> - - -<p> This class is a tool for optimized drawing with <a href="ntqpixmap.html">TQPixmap</a>. You can -use it to store temporary pixmaps that are expensive to generate -without using more storage space than <a href="#cacheLimit">cacheLimit</a>(). Use <a href="#insert">insert</a>() -to insert pixmaps, <a href="#find">find</a>() to find them and <a href="#clear">clear</a>() to empty the -cache. -<p> For example, <a href="ntqradiobutton.html">TQRadioButton</a> 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 -<a href="ntqbutton.html#drawButton">TQRadioButton::drawButton</a>(), 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 <tt>nnn</tt> is a numerical -value that specifies the the radio button state. If a pixmap is -found, we <a href="tqimage.html#bitBlt">bitBlt</a>() 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 TQPixmapCache is application-global. -<p> TQPixmapCache contains no member data, only static functions to -access the global pixmap cache. It creates an internal <a href="tqcache.html">TQCache</a> for -caching the pixmaps. -<p> 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 <a href="tqdict.html">TQDict</a> and TQCache classes do -exactly the same. -<p> The cache becomes full when the total size of all pixmaps in the -cache exceeds <a href="#cacheLimit">cacheLimit</a>(). The initial cache limit is 1024 KByte -(1 MByte); it is changed with <a href="#setCacheLimit">setCacheLimit</a>(). A pixmap takes -roughly width*height*depth/8 bytes of memory. -<p> See the <a href="tqcache.html">TQCache</a> documentation for more details about the cache -mechanism. -<p>See also <a href="environment.html">Environment Classes</a>, <a href="graphics.html">Graphics Classes</a>, and <a href="images.html">Image Processing Classes</a>. - -<hr><h2>Member Function Documentation</h2> -<h3 class=fn>int <a name="cacheLimit"></a>TQPixmapCache::cacheLimit ()<tt> [static]</tt> -</h3> -Returns the cache limit (in kilobytes). -<p> The default setting is 1024 kilobytes. -<p> <p>See also <a href="#setCacheLimit">setCacheLimit</a>(). - -<h3 class=fn>void <a name="clear"></a>TQPixmapCache::clear ()<tt> [static]</tt> -</h3> -Removes all pixmaps from the cache. - -<h3 class=fn><a href="ntqpixmap.html">TQPixmap</a> * <a name="find"></a>TQPixmapCache::find ( const <a href="tqstring.html">TQString</a> & key )<tt> [static]</tt> -</h3> -Returns the pixmap associated with the <em>key</em> in the cache, or -null if there is no such pixmap. -<p> <b>Warning:</b> 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 -<a href="#find">find</a>(const <a href="tqstring.html">TQString</a>&, <a href="ntqpixmap.html">TQPixmap</a>&) instead. -<p> Example: -<pre> - <a href="ntqpixmap.html">TQPixmap</a>* pp; - <a href="ntqpixmap.html">TQPixmap</a> p; - if ( (pp=TQPixmapCache::<a href="#find">find</a>("my_big_image", pm)) ) { - p = *pp; - } else { - p.<a href="ntqpixmap.html#load">load</a>("bigimage.png"); - TQPixmapCache::<a href="#insert">insert</a>("my_big_image", new <a href="ntqpixmap.html">TQPixmap</a>(p)); - } - painter->drawPixmap(0, 0, p); - </pre> - - -<h3 class=fn>bool <a name="find-2"></a>TQPixmapCache::find ( const <a href="tqstring.html">TQString</a> & key, <a href="ntqpixmap.html">TQPixmap</a> & pm )<tt> [static]</tt> -</h3> -This is an overloaded member function, provided for convenience. It behaves essentially like the above function. -<p> Looks for a cached pixmap associated with the <em>key</em> in the cache. -If a pixmap is found, the function sets <em>pm</em> to that pixmap and -returns TRUE; otherwise leaves <em>pm</em> alone and returns FALSE. -<p> Example: -<pre> - <a href="ntqpixmap.html">TQPixmap</a> p; - if ( !TQPixmapCache::find("my_big_image", pm) ) { - pm.load("bigimage.png"); - TQPixmapCache::<a href="#insert">insert</a>("my_big_image", pm); - } - painter->drawPixmap(0, 0, p); - </pre> - - -<h3 class=fn>bool <a name="insert"></a>TQPixmapCache::insert ( const <a href="tqstring.html">TQString</a> & key, const <a href="ntqpixmap.html">TQPixmap</a> & pm )<tt> [static]</tt> -</h3> -Inserts a copy of the pixmap <em>pm</em> associated with the <em>key</em> into -the cache. -<p> All pixmaps inserted by the TQt library have a key starting with -"$qt", so your own pixmap keys should never begin "$qt". -<p> 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. -<p> The oldest pixmaps (least recently accessed in the cache) are -deleted when more space is needed. -<p> <p>See also <a href="#setCacheLimit">setCacheLimit</a>(). - -<h3 class=fn>bool <a name="insert-2"></a>TQPixmapCache::insert ( const <a href="tqstring.html">TQString</a> & key, <a href="ntqpixmap.html">TQPixmap</a> * pm )<tt> [static]</tt> -</h3> -<b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code. -<p> Inserts the pixmap <em>pm</em> associated with <em>key</em> into the cache. -Returns TRUE if successful, or FALSE if the pixmap is too big for the cache. -<p> <strong> -Note: <em>pm</em> must be allocated on the heap (using <tt>new</tt>). -<p> If this function returns FALSE, you must delete <em>pm</em> yourself. -<p> If this function returns TRUE, do not use <em>pm</em> afterwards or -keep references to it because any other insertions into the cache, -whether from anywhere in the application or within TQt itself, could cause -the pixmap to be discarded from the cache and the pointer to -become invalid. -<p> Due to these dangers, we strongly recommend that you use -<a href="#insert">insert</a>(const <a href="tqstring.html">TQString</a>&, const <a href="ntqpixmap.html">TQPixmap</a>&) instead. -</strong> - -<h3 class=fn>void <a name="remove"></a>TQPixmapCache::remove ( const <a href="tqstring.html">TQString</a> & key )<tt> [static]</tt> -</h3> -Removes the pixmap associated with <em>key</em> from the cache. - -<h3 class=fn>void <a name="setCacheLimit"></a>TQPixmapCache::setCacheLimit ( int n )<tt> [static]</tt> -</h3> -Sets the cache limit to <em>n</em> kilobytes. -<p> The default setting is 1024 kilobytes. -<p> <p>See also <a href="#cacheLimit">cacheLimit</a>(). - -<!-- eof --> -<hr><p> -This file is part of the <a href="index.html">TQt toolkit</a>. -Copyright © 1995-2007 -<a href="http://www.trolltech.com/">Trolltech</a>. 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