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diff --git a/doc/html/qdirectpainter.html b/doc/html/qdirectpainter.html new file mode 100644 index 0000000..c4eea9d --- /dev/null +++ b/doc/html/qdirectpainter.html @@ -0,0 +1,201 @@ +<!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/qdirectpainter_qws.cpp:72 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QDirectPainter 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>QDirectPainter Class Reference</h1> + +<p>The QDirectPainter class provides direct access to the video hardware. +<a href="#details">More...</a> +<p><tt>#include <<a href="qdirectpainter_qws-h.html">qdirectpainter_qws.h</a>></tt> +<p>Inherits <a href="qpainter.html">QPainter</a>. +<p><a href="qdirectpainter-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn><a href="#QDirectPainter"><b>QDirectPainter</b></a> ( const QWidget * w )</li> +<li class=fn><a href="#~QDirectPainter"><b>~QDirectPainter</b></a> ()</li> +<li class=fn>uchar * <a href="#frameBuffer"><b>frameBuffer</b></a> ()</li> +<li class=fn>int <a href="#lineStep"><b>lineStep</b></a> ()</li> +<li class=fn>int <a href="#transformOrientation"><b>transformOrientation</b></a> ()</li> +<li class=fn>int <a href="#numRects"><b>numRects</b></a> () const</li> +<li class=fn>const QRect & <a href="#rect"><b>rect</b></a> ( int i ) const</li> +<li class=fn>QRegion <a href="#region"><b>region</b></a> () const</li> +<li class=fn>int <a href="#depth"><b>depth</b></a> () const</li> +<li class=fn>int <a href="#width"><b>width</b></a> () const</li> +<li class=fn>int <a href="#height"><b>height</b></a> () const</li> +<li class=fn>int <a href="#xOffset"><b>xOffset</b></a> () const</li> +<li class=fn>int <a href="#yOffset"><b>yOffset</b></a> () const</li> +<li class=fn>QPoint <a href="#offset"><b>offset</b></a> () const</li> +<li class=fn>QSize <a href="#size"><b>size</b></a> () const</li> +<li class=fn>void <a href="#setAreaChanged"><b>setAreaChanged</b></a> ( const QRect & r )</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The QDirectPainter class provides direct access to the video hardware. +<p> +<p> Only available in Qt/Embedded. +<p> When the hardware is known and well defined, as is often the case +with software for embedded devices, it may be useful to manipulate +the underlying video hardware directly. In order to do this in a +way that is co-operative with other applications, you must lock +the video hardware for exclusive use for a small time while you +write to it, and you must know the clipping region which is +allocated to a widget. +<p> QDirectPainter provides this functionality. +<p> In the simplest case, you make a QDirectPainter on a widget and +then, observing the clip region, perform some platform-specific +operation. For example: +<pre> + void MyWidget::updatePlatformGraphics() + { + QDirectPainter dp( this ); + for ( int i = 0; i < dp.numRects; i++ ) { + const <a href="qrect.html">QRect</a>& clip = dp.<a href="#rect">rect</a>(i); + ... // platform specific operation + } + } + </pre> + +<p> The platform-specific code has access to the display, but should +only modify graphics in the rectangles specified by <a href="#numRects">numRects</a>() and +<a href="#rect">rect</a>(). Note that these rectangles are relative to the entire +display. +<p> The <a href="#offset">offset</a>() function returns the position of the widget relative +to the entire display, allowing you to offset platform-specific +operations appropriately. The <a href="#xOffset">xOffset</a>() and <a href="#yOffset">yOffset</a>() functions +merely return the component values of offset(). +<p> For simple frame-buffer hardware, the <a href="#frameBuffer">frameBuffer</a>(), <a href="#lineStep">lineStep</a>(), +and <a href="#depth">depth</a>() functions provide basic access, though some hardware +configurations are insufficiently specified by such simple +parameters. +<p> Note that while a QDirectPainter exists, the entire Qt/Embedded +window system is locked from use by other applications. Always +construct the QDirectPainter as an auto (stack) variable, and be +very careful to write robust and stable code within its scope. +<p>See also <a href="graphics.html">Graphics Classes</a>. + +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="QDirectPainter"></a>QDirectPainter::QDirectPainter ( const <a href="qwidget.html">QWidget</a> * w ) +</h3> +Construct a direct painter on <em>w</em>. The display is locked and the +mouse cursor is hidden if it is above <em>w</em>. + +<h3 class=fn><a name="~QDirectPainter"></a>QDirectPainter::~QDirectPainter () +</h3> +Destroys the direct painter. The mouse cursor is revealed if +necessary and the display is unlocked. + +<h3 class=fn>int <a name="depth"></a>QDirectPainter::depth () const +</h3> +Returns the bit-depth of the display. + +<h3 class=fn>uchar * <a name="frameBuffer"></a>QDirectPainter::frameBuffer () +</h3> +Returns a pointer to the framebuffer memory if available. + +<h3 class=fn>int <a name="height"></a>QDirectPainter::height () const +</h3> +Returns the height of the widget drawn upon. + +<h3 class=fn>int <a name="lineStep"></a>QDirectPainter::lineStep () +</h3> +Returns the spacing in bytes from one framebuffer line to the +next. + +<h3 class=fn>int <a name="numRects"></a>QDirectPainter::numRects () const +</h3> +Returns the number of rectangles in the drawable region. +<p> <p>See also <a href="#rect">rect</a>() and <a href="#region">region</a>(). + +<h3 class=fn><a href="qpoint.html">QPoint</a> <a name="offset"></a>QDirectPainter::offset () const +</h3> +Returns the position of the widget relative to the entire display. + +<h3 class=fn>const <a href="qrect.html">QRect</a> & <a name="rect"></a>QDirectPainter::rect ( int i ) const +</h3> +Returns a reference to rectangle <em>i</em> of the drawable region. +Valid values for <em>i</em> are 0..<a href="#numRects">numRects</a>()-1. +<p> <p>See also <a href="#region">region</a>(). + +<h3 class=fn><a href="qregion.html">QRegion</a> <a name="region"></a>QDirectPainter::region () const +</h3> +Returns the region of the framebuffer which represents the exposed +area of the widget being painted on. Note that this may be a sub-area of +the clip region, because of child widgets and overlapping cousin widgets. +<p> <p>See also <a href="#numRects">numRects</a>() and <a href="#rect">rect</a>(). + +<h3 class=fn>void <a name="setAreaChanged"></a>QDirectPainter::setAreaChanged ( const <a href="qrect.html">QRect</a> & r ) +</h3> +Sets the area changed by the transaction to <em>r</em>. By default, the +entire widget is assumed to have changed. The area changed is only +used by some graphics drivers, so often calling this function for +a smaller area will make no difference to performance. + +<h3 class=fn><a href="qsize.html">QSize</a> <a name="size"></a>QDirectPainter::size () const +</h3> +Returns the size of the widget drawn upon. +<p> <p>See also <a href="#width">width</a>() and <a href="#height">height</a>(). + +<h3 class=fn>int <a name="transformOrientation"></a>QDirectPainter::transformOrientation () +</h3> +Returns a number that signifies the orientation of the +framebuffer. +<center><table cellpadding="4" cellspacing="2" border="0"> +<tr bgcolor="#f0f0f0"> <td valign="top" colspan="1" rowspan="1"> 0 <td valign="top" colspan="1" rowspan="1"> no rotation +<tr bgcolor="#d0d0d0"> <td valign="top" colspan="1" rowspan="1"> 1 <td valign="top" colspan="1" rowspan="1"> 90 degrees rotation +<tr bgcolor="#f0f0f0"> <td valign="top" colspan="1" rowspan="1"> 2 <td valign="top" colspan="1" rowspan="1"> 180 degrees rotation +<tr bgcolor="#d0d0d0"> <td valign="top" colspan="1" rowspan="1"> 3 <td valign="top" colspan="1" rowspan="1"> 270 degrees rotation +</table></center> + +<h3 class=fn>int <a name="width"></a>QDirectPainter::width () const +</h3> +Returns the width of the widget drawn upon. + +<h3 class=fn>int <a name="xOffset"></a>QDirectPainter::xOffset () const +</h3> +Returns the X-position of the widget relative to the entire +display. + +<h3 class=fn>int <a name="yOffset"></a>QDirectPainter::yOffset () const +</h3> +Returns the Y-position of the widget relative to the entire +display. + +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">Qt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. 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