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diff --git a/doc/html/qglcontext.html b/doc/html/qglcontext.html new file mode 100644 index 0000000..4544861 --- /dev/null +++ b/doc/html/qglcontext.html @@ -0,0 +1,344 @@ +<!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/opengl/qgl.cpp:733 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QGLContext 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>QGLContext Class Reference<br><small>[<a href="opengl.html">OpenGL module</a>]</small></h1> + +<p>The QGLContext class encapsulates an OpenGL rendering context. +<a href="#details">More...</a> +<p><tt>#include <<a href="qgl-h.html">qgl.h</a>></tt> +<p>Inherits <a href="qgl.html">QGL</a>. +<p><a href="qglcontext-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn><a href="#QGLContext"><b>QGLContext</b></a> ( const QGLFormat & format, QPaintDevice * device )</li> +<li class=fn>virtual <a href="#~QGLContext"><b>~QGLContext</b></a> ()</li> +<li class=fn>virtual bool <a href="#create"><b>create</b></a> ( const QGLContext * shareContext = 0 )</li> +<li class=fn>bool <a href="#isValid"><b>isValid</b></a> () const</li> +<li class=fn>bool <a href="#isSharing"><b>isSharing</b></a> () const</li> +<li class=fn>virtual void <a href="#reset"><b>reset</b></a> ()</li> +<li class=fn>QGLFormat <a href="#format"><b>format</b></a> () const</li> +<li class=fn>QGLFormat <a href="#requestedFormat"><b>requestedFormat</b></a> () const</li> +<li class=fn>virtual void <a href="#setFormat"><b>setFormat</b></a> ( const QGLFormat & format )</li> +<li class=fn>virtual void <a href="#makeCurrent"><b>makeCurrent</b></a> ()</li> +<li class=fn>virtual void <a href="#swapBuffers"><b>swapBuffers</b></a> () const</li> +<li class=fn>QPaintDevice * <a href="#device"><b>device</b></a> () const</li> +<li class=fn>QColor <a href="#overlayTransparentColor"><b>overlayTransparentColor</b></a> () const</li> +</ul> +<h2>Static Public Members</h2> +<ul> +<li class=fn>const QGLContext * <a href="#currentContext"><b>currentContext</b></a> ()</li> +</ul> +<h2>Protected Members</h2> +<ul> +<li class=fn>virtual bool <a href="#chooseContext"><b>chooseContext</b></a> ( const QGLContext * shareContext = 0 )</li> +<li class=fn>virtual void <a href="#doneCurrent"><b>doneCurrent</b></a> ()</li> +<li class=fn>virtual int <a href="#choosePixelFormat"><b>choosePixelFormat</b></a> ( void * dummyPfd, HDC pdc )</li> +<li class=fn>virtual void * <a href="#chooseVisual"><b>chooseVisual</b></a> ()</li> +<li class=fn>virtual void * <a href="#chooseMacVisual"><b>chooseMacVisual</b></a> ( GDHandle device )</li> +<li class=fn>bool <a href="#deviceIsPixmap"><b>deviceIsPixmap</b></a> () const</li> +<li class=fn>bool <a href="#windowCreated"><b>windowCreated</b></a> () const</li> +<li class=fn>void <a href="#setWindowCreated"><b>setWindowCreated</b></a> ( bool on )</li> +<li class=fn>bool <a href="#initialized"><b>initialized</b></a> () const</li> +<li class=fn>void <a href="#setInitialized"><b>setInitialized</b></a> ( bool on )</li> +<li class=fn>void <a href="#generateFontDisplayLists"><b>generateFontDisplayLists</b></a> ( const QFont & font, int listBase )</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The QGLContext class encapsulates an OpenGL rendering context. + +<p> + + +<p> An OpenGL<sup>*</sup> rendering context is a complete set of +OpenGL state variables. +<p> The context's <a href="qgl.html#FormatOption-enum">format</a> is set in the +constructor or later with <a href="#setFormat">setFormat</a>(). The format options that are +actually set are returned by <a href="#format">format</a>(); the options you asked for +are returned by <a href="#requestedFormat">requestedFormat</a>(). Note that after a QGLContext +object has been constructed, the actual OpenGL context must be +created by explicitly calling the <a href="#create">create()</a> +function. The <a href="#makeCurrent">makeCurrent</a>() function makes this context the +current rendering context. You can make <em>no</em> context current +using <a href="#doneCurrent">doneCurrent</a>(). The <a href="#reset">reset</a>() function will reset the context +and make it invalid. +<p> You can examine properties of the context with, e.g. <a href="#isValid">isValid</a>(), +<a href="#isSharing">isSharing</a>(), <a href="#initialized">initialized</a>(), <a href="#windowCreated">windowCreated</a>() and +<a href="#overlayTransparentColor">overlayTransparentColor</a>(). +<p> If you're using double buffering you can swap the screen contents +with the off-screen buffer using <a href="#swapBuffers">swapBuffers</a>(). +<p> Please note that QGLContext is not thread safe. +<p> <sup>*</sup> OpenGL is a trademark of Silicon Graphics, Inc. in the +United States and other countries. +<p> <p>See also <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><a name="QGLContext"></a>QGLContext::QGLContext ( const <a href="qglformat.html">QGLFormat</a> & format, <a href="qpaintdevice.html">QPaintDevice</a> * device ) +</h3> +Constructs an OpenGL context for the paint device <em>device</em>, which +can be a widget or a pixmap. The <em>format</em> specifies several +display options for the context. +<p> If the underlying OpenGL/Window system cannot satisfy all the +features requested in <em>format</em>, the nearest subset of features +will be used. After creation, the <a href="#format">format</a>() method will return the +actual format obtained. +<p> Note that after a QGLContext object has been constructed, <a href="#create">create()</a> must be called explicitly to create +the actual OpenGL context. The context will be <a href="#isValid">invalid</a> if it was not possible to obtain a GL context at +all. +<p> <p>See also <a href="#format">format</a>() and <a href="#isValid">isValid</a>(). + +<h3 class=fn><a name="~QGLContext"></a>QGLContext::~QGLContext ()<tt> [virtual]</tt> +</h3> +Destroys the OpenGL context and frees its resources. + +<h3 class=fn>bool <a name="chooseContext"></a>QGLContext::chooseContext ( const <a href="qglcontext.html">QGLContext</a> * shareContext = 0 )<tt> [virtual protected]</tt> +</h3> + +<p> This semi-internal function is called by <a href="#create">create</a>(). It creates a +system-dependent OpenGL handle that matches the <a href="#format">format</a>() of <em>shareContext</em> as closely as possible. +<p> On Windows, it calls the virtual function <a href="#choosePixelFormat">choosePixelFormat</a>(), +which finds a matching pixel format identifier. On X11, it calls +the virtual function <a href="#chooseVisual">chooseVisual</a>() which finds an appropriate X +visual. On other platforms it may work differently. + +<h3 class=fn>void * <a name="chooseMacVisual"></a>QGLContext::chooseMacVisual ( GDHandle device )<tt> [virtual protected]</tt> +</h3> + +<p> <strong>Mac only</strong>: This virtual function tries to find a +visual that matches the format using the given <em>device</em> handle, +reducing the demands if the original request cannot be met. +<p> The algorithm for reducing the demands of the format is quite +simple-minded, so override this method in your subclass if your +application has specific requirements on visual selection. +<p> <p>See also <a href="#chooseContext">chooseContext</a>(). + +<h3 class=fn>int <a name="choosePixelFormat"></a>QGLContext::choosePixelFormat ( void * dummyPfd, HDC pdc )<tt> [virtual protected]</tt> +</h3> +<strong>Win32 only</strong> This virtual function chooses a pixel +format that matches the OpenGL <a href="#setFormat">format</a>. +Reimplement this function in a subclass if you need a custom +context. +<p> <b>Warning:</b> The <em>dummyPfd</em> pointer and <em>pdc</em> are used as a <tt>PIXELFORMATDESCRIPTOR*</tt>. We use <tt>void</tt> to avoid using +Windows-specific types in our header files. +<p> <p>See also <a href="#chooseContext">chooseContext</a>(). + +<h3 class=fn>void * <a name="chooseVisual"></a>QGLContext::chooseVisual ()<tt> [virtual protected]</tt> +</h3> +<strong>X11 only</strong>: This virtual function tries to find a +visual that matches the format, reducing the demands if the original +request cannot be met. +<p> The algorithm for reducing the demands of the format is quite +simple-minded, so override this method in your subclass if your +application has spcific requirements on visual selection. +<p> <p>See also <a href="#chooseContext">chooseContext</a>(). + +<h3 class=fn>bool <a name="create"></a>QGLContext::create ( const <a href="qglcontext.html">QGLContext</a> * shareContext = 0 )<tt> [virtual]</tt> +</h3> +Creates the GL context. Returns TRUE if it was successful in +creating a valid GL rendering context on the paint device +specified in the constructor; otherwise returns FALSE (i.e. the +context is invalid). +<p> After successful creation, <a href="#format">format</a>() returns the set of features of +the created GL rendering context. +<p> If <em>shareContext</em> points to a valid QGLContext, this method will +try to establish OpenGL display list sharing between this context +and the <em>shareContext</em>. Note that this may fail if the two +contexts have different formats. Use <a href="#isSharing">isSharing</a>() to see if sharing +succeeded. +<p> <b>Warning:</b> Implementation note: initialization of C++ class +members usually takes place in the class constructor. QGLContext +is an exception because it must be simple to customize. The +virtual functions <a href="#chooseContext">chooseContext</a>() (and <a href="#chooseVisual">chooseVisual</a>() for X11) can +be reimplemented in a subclass to select a particular context. The +problem is that virtual functions are not properly called during +construction (even though this is correct C++) because C++ +constructs class hierarchies from the bottom up. For this reason +we need a <a href="#create">create</a>() function. +<p> <p>See also <a href="#chooseContext">chooseContext</a>(), <a href="#format">format</a>(), and <a href="#isValid">isValid</a>(). + +<h3 class=fn>const <a href="qglcontext.html">QGLContext</a> * <a name="currentContext"></a>QGLContext::currentContext ()<tt> [static]</tt> +</h3> + +<p> Returns the current context, i.e. the context to which any OpenGL +commands will currently be directed. Returns 0 if no context is +current. +<p> <p>See also <a href="#makeCurrent">makeCurrent</a>(). + +<h3 class=fn><a href="qpaintdevice.html">QPaintDevice</a> * <a name="device"></a>QGLContext::device () const +</h3> + +<p> Returns the paint device set for this context. +<p> <p>See also <a href="#QGLContext">QGLContext::QGLContext</a>(). + +<h3 class=fn>bool <a name="deviceIsPixmap"></a>QGLContext::deviceIsPixmap () const<tt> [protected]</tt> +</h3> + +<p> Returns TRUE if the paint device of this context is a pixmap; +otherwise returns FALSE. + +<h3 class=fn>void <a name="doneCurrent"></a>QGLContext::doneCurrent ()<tt> [virtual protected]</tt> +</h3> + +<p> Makes no GL context the current context. Normally, you do not need +to call this function; QGLContext calls it as necessary. + +<h3 class=fn><a href="qglformat.html">QGLFormat</a> <a name="format"></a>QGLContext::format () const +</h3> + +<p> Returns the frame buffer format that was obtained (this may be a +subset of what was requested). +<p> <p>See also <a href="#requestedFormat">requestedFormat</a>(). + +<h3 class=fn>void <a name="generateFontDisplayLists"></a>QGLContext::generateFontDisplayLists ( const <a href="qfont.html">QFont</a> & font, int listBase )<tt> [protected]</tt> +</h3> + +<p> Generates a set of 256 display lists for the 256 first characters +in the font <em>font</em>. The first list will start at index <em>listBase</em>. +<p> <p>See also <a href="qglwidget.html#renderText">QGLWidget::renderText</a>(). + +<h3 class=fn>bool <a name="initialized"></a>QGLContext::initialized () const<tt> [protected]</tt> +</h3> + +<p> Returns TRUE if this context has been initialized, i.e. if +<a href="qglwidget.html#initializeGL">QGLWidget::initializeGL</a>() has been performed on it; otherwise +returns FALSE. +<p> <p>See also <a href="#setInitialized">setInitialized</a>(). + +<h3 class=fn>bool <a name="isSharing"></a>QGLContext::isSharing () const +</h3> + +<p> Returns TRUE if display list sharing with another context was +requested in the <a href="#create">create</a>() call and the GL system was able to +fulfill this request; otherwise returns FALSE. Note that display +list sharing might not be supported between contexts with +different formats. + +<h3 class=fn>bool <a name="isValid"></a>QGLContext::isValid () const +</h3> + +<p> Returns TRUE if a GL rendering context has been successfully +created; otherwise returns FALSE. + +<h3 class=fn>void <a name="makeCurrent"></a>QGLContext::makeCurrent ()<tt> [virtual]</tt> +</h3> + +<p> Makes this context the current OpenGL rendering context. All GL +functions you call operate on this context until another context +is made current. +<p> In some very rare cases the underlying call may fail. If this +occurs an error message is output to stderr. + +<h3 class=fn><a href="qcolor.html">QColor</a> <a name="overlayTransparentColor"></a>QGLContext::overlayTransparentColor () const +</h3> + +<p> If this context is a valid context in an overlay plane, returns +the plane's transparent color. Otherwise returns an <a href="qcolor.html#isValid">invalid</a> color. +<p> The returned color's <a href="qcolor.html#pixel">pixel</a> value is +the index of the transparent color in the colormap of the overlay +plane. (Naturally, the color's RGB values are meaningless.) +<p> The returned <a href="qcolor.html">QColor</a> object will generally work as expected only +when passed as the argument to <a href="qglwidget.html#qglColor">QGLWidget::qglColor</a>() or +<a href="qglwidget.html#qglClearColor">QGLWidget::qglClearColor</a>(). Under certain circumstances it can +also be used to draw transparent graphics with a <a href="qpainter.html">QPainter</a>. See the +examples/opengl/overlay_x11 example for details. + +<h3 class=fn><a href="qglformat.html">QGLFormat</a> <a name="requestedFormat"></a>QGLContext::requestedFormat () const +</h3> + +<p> Returns the frame buffer format that was originally requested in +the constructor or <a href="#setFormat">setFormat</a>(). +<p> <p>See also <a href="#format">format</a>(). + +<h3 class=fn>void <a name="reset"></a>QGLContext::reset ()<tt> [virtual]</tt> +</h3> + +<p> Resets the context and makes it invalid. +<p> <p>See also <a href="#create">create</a>() and <a href="#isValid">isValid</a>(). + +<h3 class=fn>void <a name="setFormat"></a>QGLContext::setFormat ( const <a href="qglformat.html">QGLFormat</a> & format )<tt> [virtual]</tt> +</h3> +Sets a <em>format</em> for this context. The context is <a href="#reset">reset</a>. +<p> Call <a href="#create">create</a>() to create a new GL context that tries to match the +new format. +<p> <pre> + QGLContext *cx; + // ... + <a href="qglformat.html">QGLFormat</a> f; + f.<a href="qglformat.html#setStereo">setStereo</a>( TRUE ); + cx-><a href="#setFormat">setFormat</a>( f ); + if ( !cx-><a href="#create">create</a>() ) + exit(); // no OpenGL support, or cannot render on the specified paintdevice + if ( !cx-><a href="#format">format</a>().stereo() ) + exit(); // could not create stereo context + </pre> + +<p> <p>See also <a href="#format">format</a>(), <a href="#reset">reset</a>(), and <a href="#create">create</a>(). + +<h3 class=fn>void <a name="setInitialized"></a>QGLContext::setInitialized ( bool on )<tt> [protected]</tt> +</h3> + +<p> If <em>on</em> is TRUE the context has been initialized, i.e. +<a href="#setInitialized">QGLContext::setInitialized</a>() has been called on it. If <em>on</em> is +FALSE the context has not been initialized. +<p> <p>See also <a href="#initialized">initialized</a>(). + +<h3 class=fn>void <a name="setWindowCreated"></a>QGLContext::setWindowCreated ( bool on )<tt> [protected]</tt> +</h3> + +<p> If <em>on</em> is TRUE the context has had a window created for it. If +<em>on</em> is FALSE no window has been created for the context. +<p> <p>See also <a href="#windowCreated">windowCreated</a>(). + +<h3 class=fn>void <a name="swapBuffers"></a>QGLContext::swapBuffers () const<tt> [virtual]</tt> +</h3> + +<p> Swaps the screen contents with an off-screen buffer. Only works if +the context is in double buffer mode. +<p> <p>See also <a href="qglformat.html#setDoubleBuffer">QGLFormat::setDoubleBuffer</a>(). + +<h3 class=fn>bool <a name="windowCreated"></a>QGLContext::windowCreated () const<tt> [protected]</tt> +</h3> + +<p> Returns TRUE if a window has been created for this context; +otherwise returns FALSE. +<p> <p>See also <a href="#setWindowCreated">setWindowCreated</a>(). + +<!-- 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>. All Rights Reserved.<p><address><hr><div align=center> +<table width=100% cellspacing=0 border=0><tr> +<td>Copyright © 2007 +<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a> +<td align=right><div align=right>Qt 3.3.8</div> +</table></div></address></body> +</html> |