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<h1 class="title">QBitmap Class Reference</h1>
<!-- $$$QBitmap-brief -->
<p>The QBitmap class provides monochrome (1-bit depth) pixmaps. <a href="#details">More...</a></p>
<!-- @@@QBitmap -->
<pre class="cpp"> <span class="preprocessor">#include &lt;QBitmap&gt;</span></pre><p><b>Inherits: </b><a href="qpixmap.html">QPixmap</a>.</p>
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<li><a href="qbitmap-members.html">List of all members, including inherited members</a></li>
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<a name="public-functions"></a>
<h2>Public Functions</h2>
<table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#QBitmap">QBitmap</a></b> ()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#QBitmap-2">QBitmap</a></b> ( const QPixmap &amp; <i>pixmap</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#QBitmap-3">QBitmap</a></b> ( int <i>width</i>, int <i>height</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#QBitmap-4">QBitmap</a></b> ( const QSize &amp; <i>size</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#QBitmap-5">QBitmap</a></b> ( const QString &amp; <i>fileName</i>, const char * <i>format</i> = 0 )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#dtor.QBitmap">~QBitmap</a></b> ()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#clear">clear</a></b> ()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#swap">swap</a></b> ( QBitmap &amp; <i>other</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QBitmap </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#transformed">transformed</a></b> ( const QTransform &amp; <i>matrix</i> ) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#operator-QVariant">operator QVariant</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QBitmap &amp; </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#operator-eq">operator=</a></b> ( const QPixmap &amp; <i>pixmap</i> )</td></tr>
</table>
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<li class="fn">48 public functions inherited from <a href="qpixmap.html#public-functions">QPixmap</a></li>
<li class="fn">13 public functions inherited from <a href="qpaintdevice.html#public-functions">QPaintDevice</a></li>
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<h2>Static Public Members</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> QBitmap </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#fromData">fromData</a></b> ( const QSize &amp; <i>size</i>, const uchar * <i>bits</i>, QImage::Format <i>monoFormat</i> = QImage::Format_MonoLSB )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QBitmap </td><td class="memItemRight bottomAlign"><b><a href="qbitmap.html#fromImage">fromImage</a></b> ( const QImage &amp; <i>image</i>, Qt::ImageConversionFlags <i>flags</i> = Qt::AutoColor )</td></tr>
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<li class="fn">14 static public members inherited from <a href="qpixmap.html#static-public-members">QPixmap</a></li>
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<h3>Additional Inherited Members</h3>
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<li class="fn">1 protected function inherited from <a href="qpaintdevice.html#protected-functions">QPaintDevice</a></li>
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<a name="details"></a>
<!-- $$$QBitmap-description -->
<div class="descr">
<h2>Detailed Description</h2>
<p>The QBitmap class provides monochrome (1-bit depth) pixmaps.</p>
<p>The QBitmap class is a monochrome off-screen paint device used mainly for creating custom <a href="qcursor.html">QCursor</a> and <a href="qbrush.html">QBrush</a> objects, constructing <a href="qregion.html">QRegion</a> objects, and for setting masks for pixmaps and widgets.</p>
<p>QBitmap is a <a href="qpixmap.html">QPixmap</a> subclass ensuring a depth of 1, except for null objects which have a depth of 0. If a pixmap with a depth greater than 1 is assigned to a bitmap, the bitmap will be dithered automatically.</p>
<p>Use the <a href="qcolor.html">QColor</a> objects <a href="qt.html#GlobalColor-enum">Qt::color0</a> and <a href="qt.html#GlobalColor-enum">Qt::color1</a> when drawing on a QBitmap object (or a <a href="qpixmap.html">QPixmap</a> object with depth 1).</p>
<p>Painting with <a href="qt.html#GlobalColor-enum">Qt::color0</a> sets the bitmap bits to 0, and painting with <a href="qt.html#GlobalColor-enum">Qt::color1</a> sets the bits to 1. For a bitmap, 0-bits indicate background (or transparent pixels) and 1-bits indicate foreground (or opaque pixels). Use the <a href="qbitmap.html#clear">clear</a>() function to set all the bits to <a href="qt.html#GlobalColor-enum">Qt::color0</a>. Note that using the <a href="qt.html#GlobalColor-enum">Qt::black</a> and <a href="qt.html#GlobalColor-enum">Qt::white</a> colors make no sense because the <a href="qcolor-qt3.html#pixel" class="compat">QColor::pixel</a>() value is not necessarily 0 for black and 1 for white.</p>
<p>The QBitmap class provides the <a href="qbitmap.html#transformed">transformed</a>() function returning a transformed copy of the bitmap; use the <a href="qtransform.html">QTransform</a> argument to translate, scale, shear, and rotate the bitmap. In addition, QBitmap provides the static <a href="qbitmap.html#fromData">fromData</a>() function which returns a bitmap constructed from the given <tt>uchar</tt> data, and the static <a href="qbitmap.html#fromImage">fromImage</a>() function returning a converted copy of a <a href="qimage.html">QImage</a> object.</p>
<p>Just like the <a href="qpixmap.html">QPixmap</a> class, QBitmap is optimized by the use of implicit data sharing. For more information, see the <a href="implicit-sharing.html#implicit-data-sharing">Implicit Data Sharing</a> documentation.</p>
</div>
<p><b>See also </b><a href="qpixmap.html">QPixmap</a>, <a href="qimage.html">QImage</a>, <a href="qimagereader.html">QImageReader</a>, and <a href="qimagewriter.html">QImageWriter</a>.</p>
<!-- @@@QBitmap -->
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$QBitmap[overload1]$$$QBitmap -->
<h3 class="fn"><a name="QBitmap"></a>QBitmap::<span class="name">QBitmap</span> ()</h3>
<p>Constructs a null bitmap.</p>
<p><b>See also </b><a href="qpixmap.html#isNull">QPixmap::isNull</a>().</p>
<!-- @@@QBitmap -->
<!-- $$$QBitmap$$$QBitmapconstQPixmap& -->
<h3 class="fn"><a name="QBitmap-2"></a>QBitmap::<span class="name">QBitmap</span> ( const <span class="type"><a href="qpixmap.html">QPixmap</a></span> &amp; <i>pixmap</i> )</h3>
<p>Constructs a bitmap that is a copy of the given <i>pixmap</i>.</p>
<p>If the pixmap has a depth greater than 1, the resulting bitmap will be dithered automatically.</p>
<p><b>See also </b><a href="qpixmap.html#depth">QPixmap::depth</a>(), <a href="qbitmap.html#fromImage">fromImage</a>(), and <a href="qbitmap.html#fromData">fromData</a>().</p>
<!-- @@@QBitmap -->
<!-- $$$QBitmap$$$QBitmapintint -->
<h3 class="fn"><a name="QBitmap-3"></a>QBitmap::<span class="name">QBitmap</span> ( <span class="type">int</span> <i>width</i>, <span class="type">int</span> <i>height</i> )</h3>
<p>Constructs a bitmap with the given <i>width</i> and <i>height</i>. The pixels inside are uninitialized.</p>
<p><b>See also </b><a href="qbitmap.html#clear">clear</a>().</p>
<!-- @@@QBitmap -->
<!-- $$$QBitmap$$$QBitmapconstQSize& -->
<h3 class="fn"><a name="QBitmap-4"></a>QBitmap::<span class="name">QBitmap</span> ( const <span class="type"><a href="qsize.html">QSize</a></span> &amp; <i>size</i> )</h3>
<p>Constructs a bitmap with the given <i>size</i>. The pixels in the bitmap are uninitialized.</p>
<p><b>See also </b><a href="qbitmap.html#clear">clear</a>().</p>
<!-- @@@QBitmap -->
<!-- $$$QBitmap$$$QBitmapconstQString&constchar* -->
<h3 class="fn"><a name="QBitmap-5"></a>QBitmap::<span class="name">QBitmap</span> ( const <span class="type"><a href="qstring.html">QString</a></span> &amp; <i>fileName</i>, const <span class="type">char</span> * <i>format</i> = 0 )</h3>
<p>Constructs a bitmap from the file specified by the given <i>fileName</i>. If the file does not exist, or has an unknown format, the bitmap becomes a null bitmap.</p>
<p>The <i>fileName</i> and <i>format</i> parameters are passed on to the <a href="qpixmap.html#load">QPixmap::load</a>() function. If the file format uses more than 1 bit per pixel, the resulting bitmap will be dithered automatically.</p>
<p><b>See also </b><a href="qpixmap.html#isNull">QPixmap::isNull</a>() and <a href="qimagereader.html#imageFormat">QImageReader::imageFormat</a>().</p>
<!-- @@@QBitmap -->
<!-- $$$~QBitmap[overload1]$$$~QBitmap -->
<h3 class="fn"><a name="dtor.QBitmap"></a>QBitmap::<span class="name">~QBitmap</span> ()</h3>
<p>Destroys the bitmap.</p>
<!-- @@@~QBitmap -->
<!-- $$$clear[overload1]$$$clear -->
<h3 class="fn"><a name="clear"></a><span class="type">void</span> QBitmap::<span class="name">clear</span> ()</h3>
<p>Clears the bitmap, setting all its bits to <a href="qt.html#GlobalColor-enum">Qt::color0</a>.</p>
<!-- @@@clear -->
<!-- $$$fromData[overload1]$$$fromDataconstQSize&constuchar*QImage::Format -->
<h3 class="fn"><a name="fromData"></a><span class="type">QBitmap</span> QBitmap::<span class="name">fromData</span> ( const <span class="type"><a href="qsize.html">QSize</a></span> &amp; <i>size</i>, const <span class="type"><a href="qtglobal.html#uchar-typedef">uchar</a></span> * <i>bits</i>, <span class="type"><a href="qimage.html#Format-enum">QImage::Format</a></span> <i>monoFormat</i> = QImage::Format_MonoLSB )<tt> [static]</tt></h3>
<p>Constructs a bitmap with the given <i>size</i>, and sets the contents to the <i>bits</i> supplied.</p>
<p>The bitmap data has to be byte aligned and provided in in the bit order specified by <i>monoFormat</i>. The mono format must be either <a href="qimage.html#Format-enum">QImage::Format_Mono</a> or <a href="qimage.html#Format-enum">QImage::Format_MonoLSB</a>. Use <a href="qimage.html#Format-enum">QImage::Format_Mono</a> to specify data on the XBM format.</p>
<p><b>See also </b><a href="qbitmap.html#fromImage">fromImage</a>().</p>
<!-- @@@fromData -->
<!-- $$$fromImage[overload1]$$$fromImageconstQImage&Qt::ImageConversionFlags -->
<h3 class="fn"><a name="fromImage"></a><span class="type">QBitmap</span> QBitmap::<span class="name">fromImage</span> ( const <span class="type"><a href="qimage.html">QImage</a></span> &amp; <i>image</i>, <span class="type"><a href="qt.html#ImageConversionFlag-enum">Qt::ImageConversionFlags</a></span> <i>flags</i> = Qt::AutoColor )<tt> [static]</tt></h3>
<p>Returns a copy of the given <i>image</i> converted to a bitmap using the specified image conversion <i>flags</i>.</p>
<p><b>See also </b><a href="qbitmap.html#fromData">fromData</a>().</p>
<!-- @@@fromImage -->
<!-- $$$swap[overload1]$$$swapQBitmap& -->
<h3 class="fn"><a name="swap"></a><span class="type">void</span> QBitmap::<span class="name">swap</span> ( <span class="type">QBitmap</span> &amp; <i>other</i> )</h3>
<p>Swaps bitmap <i>other</i> with this bitmap. This operation is very fast and never fails.</p>
<p>This function was introduced in Qt 4.8.</p>
<!-- @@@swap -->
<!-- $$$transformed[overload1]$$$transformedconstQTransform& -->
<h3 class="fn"><a name="transformed"></a><span class="type">QBitmap</span> QBitmap::<span class="name">transformed</span> ( const <span class="type"><a href="qtransform.html">QTransform</a></span> &amp; <i>matrix</i> ) const</h3>
<p>Returns a copy of this bitmap, transformed according to the given <i>matrix</i>.</p>
<p><b>See also </b><a href="qpixmap.html#transformed">QPixmap::transformed</a>().</p>
<!-- @@@transformed -->
<!-- $$$operator QVariant[overload1]$$$operator QVariant -->
<h3 class="fn"><a name="operator-QVariant"></a>QBitmap::<span class="name">operator QVariant</span> () const</h3>
<p>Returns the bitmap as a <a href="qvariant.html">QVariant</a>.</p>
<!-- @@@operator QVariant -->
<!-- $$$operator=[overload1]$$$operator=constQPixmap& -->
<h3 class="fn"><a name="operator-eq"></a><span class="type">QBitmap</span> &amp; QBitmap::<span class="name">operator=</span> ( const <span class="type"><a href="qpixmap.html">QPixmap</a></span> &amp; <i>pixmap</i> )</h3>
<p>This is an overloaded function.</p>
<p>Assigns the given <i>pixmap</i> to this bitmap and returns a reference to this bitmap.</p>
<p>If the pixmap has a depth greater than 1, the resulting bitmap will be dithered automatically.</p>
<p><b>See also </b><a href="qpixmap.html#depth">QPixmap::depth</a>().</p>
<!-- @@@operator= -->
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