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Breadcrumbs go here --> </ul> </div> <div class="toolbuttons toolblock"> <ul> <li id="smallA" class="t_button">A</li> <li id="medA" class="t_button active">A</li> <li id="bigA" class="t_button">A</li> <li id="print" class="t_button"><a href="javascript:this.print();"> <span>Print</span></a></li> </ul> </div> </div> <div class="content mainContent"> <h1 class="title">main.cpp Example File</h1> <span class="small-subtitle">demos/boxes/main.cpp</span> <!-- $$$demos/boxes/main.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2015 The Qt Company Ltd. ** Contact: http://www.qt.io/licensing/ ** ** This file is part of the demonstration applications of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see http://www.qt.io/terms-conditions. For further ** information use the contact form at http://www.qt.io/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 2.1 or version 3 as published by the Free ** Software Foundation and appearing in the file LICENSE.LGPLv21 and ** LICENSE.LGPLv3 included in the packaging of this file. Please review the ** following information to ensure the GNU Lesser General Public License ** requirements will be met: https://www.gnu.org/licenses/lgpl.html and ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** As a special exception, The Qt Company gives you certain additional ** rights. These rights are described in The Qt Company LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 3.0 as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU General Public License version 3.0 requirements will be ** met: http://www.gnu.org/copyleft/gpl.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="comment">//#include <GL/glew.h></span> <span class="preprocessor">#include "glextensions.h"</span> <span class="preprocessor">#include "scene.h"</span> <span class="preprocessor">#include <QtGui></span> <span class="preprocessor">#include <QGLWidget></span> <span class="keyword">class</span> GraphicsView : <span class="keyword">public</span> <span class="type"><a href="qgraphicsview.html">QGraphicsView</a></span> { <span class="keyword">public</span>: GraphicsView() { setWindowTitle(tr(<span class="string">"Boxes"</span>)); setRenderHints(<span class="type"><a href="qpainter.html">QPainter</a></span><span class="operator">::</span>Antialiasing <span class="operator">|</span> <span class="type"><a href="qpainter.html">QPainter</a></span><span class="operator">::</span>SmoothPixmapTransform); <span class="comment">//setRenderHints(QPainter::SmoothPixmapTransform);</span> } <span class="keyword">protected</span>: <span class="type">void</span> resizeEvent(<span class="type"><a href="qresizeevent.html">QResizeEvent</a></span> <span class="operator">*</span>event) { <span class="keyword">if</span> (scene()) scene()<span class="operator">-</span><span class="operator">></span>setSceneRect(<span class="type"><a href="qrect.html">QRect</a></span>(<span class="type"><a href="qpoint.html">QPoint</a></span>(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span>)<span class="operator">,</span> event<span class="operator">-</span><span class="operator">></span>size())); <span class="type"><a href="qgraphicsview.html">QGraphicsView</a></span><span class="operator">::</span>resizeEvent(event); } }; <span class="keyword">inline</span> <span class="type">bool</span> matchString(<span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span>extensionString<span class="operator">,</span> <span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span>subString) { <span class="type">int</span> subStringLength <span class="operator">=</span> strlen(subString); <span class="keyword">return</span> (strncmp(extensionString<span class="operator">,</span> subString<span class="operator">,</span> subStringLength) <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span>) <span class="operator">&</span><span class="operator">&</span> ((extensionString<span class="operator">[</span>subStringLength<span class="operator">]</span> <span class="operator">=</span><span class="operator">=</span> <span class="char">' '</span>) <span class="operator">|</span><span class="operator">|</span> (extensionString<span class="operator">[</span>subStringLength<span class="operator">]</span> <span class="operator">=</span><span class="operator">=</span> <span class="char">'\0'</span>)); } <span class="type">bool</span> necessaryExtensionsSupported() { <span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span>extensionString <span class="operator">=</span> <span class="keyword">reinterpret_cast</span><span class="operator"><</span><span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span><span class="operator">></span>(glGetString(GL_EXTENSIONS)); <span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span>p <span class="operator">=</span> extensionString; <span class="keyword">const</span> <span class="type">int</span> GL_EXT_FBO <span class="operator">=</span> <span class="number">1</span>; <span class="keyword">const</span> <span class="type">int</span> GL_ARB_VS <span class="operator">=</span> <span class="number">2</span>; <span class="keyword">const</span> <span class="type">int</span> GL_ARB_FS <span class="operator">=</span> <span class="number">4</span>; <span class="keyword">const</span> <span class="type">int</span> GL_ARB_SO <span class="operator">=</span> <span class="number">8</span>; <span class="type">int</span> extensions <span class="operator">=</span> <span class="number">0</span>; <span class="keyword">while</span> (<span class="operator">*</span>p) { <span class="keyword">if</span> (matchString(p<span class="operator">,</span> <span class="string">"GL_EXT_framebuffer_object"</span>)) extensions <span class="operator">|</span><span class="operator">=</span> GL_EXT_FBO; <span class="keyword">else</span> <span class="keyword">if</span> (matchString(p<span class="operator">,</span> <span class="string">"GL_ARB_vertex_shader"</span>)) extensions <span class="operator">|</span><span class="operator">=</span> GL_ARB_VS; <span class="keyword">else</span> <span class="keyword">if</span> (matchString(p<span class="operator">,</span> <span class="string">"GL_ARB_fragment_shader"</span>)) extensions <span class="operator">|</span><span class="operator">=</span> GL_ARB_FS; <span class="keyword">else</span> <span class="keyword">if</span> (matchString(p<span class="operator">,</span> <span class="string">"GL_ARB_shader_objects"</span>)) extensions <span class="operator">|</span><span class="operator">=</span> GL_ARB_SO; <span class="keyword">while</span> ((<span class="operator">*</span>p <span class="operator">!</span><span class="operator">=</span> <span class="char">' '</span>) <span class="operator">&</span><span class="operator">&</span> (<span class="operator">*</span>p <span class="operator">!</span><span class="operator">=</span> <span class="char">'\0'</span>)) <span class="operator">+</span><span class="operator">+</span>p; <span class="keyword">if</span> (<span class="operator">*</span>p <span class="operator">=</span><span class="operator">=</span> <span class="char">' '</span>) <span class="operator">+</span><span class="operator">+</span>p; } <span class="keyword">return</span> (extensions <span class="operator">=</span><span class="operator">=</span> <span class="number">15</span>); } <span class="type">int</span> main(<span class="type">int</span> argc<span class="operator">,</span> <span class="type">char</span> <span class="operator">*</span><span class="operator">*</span>argv) { <span class="type"><a href="qapplication.html">QApplication</a></span> app(argc<span class="operator">,</span> argv); <span class="keyword">if</span> ((<span class="type"><a href="qglformat.html">QGLFormat</a></span><span class="operator">::</span>openGLVersionFlags() <span class="operator">&</span> <span class="type"><a href="qglformat.html">QGLFormat</a></span><span class="operator">::</span>OpenGL_Version_1_5) <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span>) { <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>critical(<span class="number">0</span><span class="operator">,</span> <span class="string">"OpenGL features missing"</span><span class="operator">,</span> <span class="string">"OpenGL version 1.5 or higher is required to run this demo.\n"</span> <span class="string">"The program will now exit."</span>); <span class="keyword">return</span> <span class="operator">-</span><span class="number">1</span>; } <span class="type">int</span> maxTextureSize <span class="operator">=</span> <span class="number">1024</span>; <span class="type"><a href="qglwidget.html">QGLWidget</a></span> <span class="operator">*</span>widget <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qglwidget.html">QGLWidget</a></span>(<span class="type"><a href="qglformat.html">QGLFormat</a></span>(QGL<span class="operator">::</span>SampleBuffers)); widget<span class="operator">-</span><span class="operator">></span>makeCurrent(); <span class="keyword">if</span> (<span class="operator">!</span>necessaryExtensionsSupported()) { <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>critical(<span class="number">0</span><span class="operator">,</span> <span class="string">"OpenGL features missing"</span><span class="operator">,</span> <span class="string">"The OpenGL extensions required to run this demo are missing.\n"</span> <span class="string">"The program will now exit."</span>); <span class="keyword">delete</span> widget; <span class="keyword">return</span> <span class="operator">-</span><span class="number">2</span>; } <span class="comment">// Check if all the necessary functions are resolved.</span> <span class="keyword">if</span> (<span class="operator">!</span>getGLExtensionFunctions()<span class="operator">.</span>resolve(widget<span class="operator">-</span><span class="operator">></span>context())) { <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>critical(<span class="number">0</span><span class="operator">,</span> <span class="string">"OpenGL features missing"</span><span class="operator">,</span> <span class="string">"Failed to resolve OpenGL functions required to run this demo.\n"</span> <span class="string">"The program will now exit."</span>); <span class="keyword">delete</span> widget; <span class="keyword">return</span> <span class="operator">-</span><span class="number">3</span>; } <span class="comment">// TODO: Make conditional for final release</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>information(<span class="number">0</span><span class="operator">,</span> <span class="string">"For your information"</span><span class="operator">,</span> <span class="string">"This demo can be GPU and CPU intensive and may\n"</span> <span class="string">"work poorly or not at all on your system."</span>); widget<span class="operator">-</span><span class="operator">></span>makeCurrent(); <span class="comment">// The current context must be set before calling Scene's constructor</span> Scene scene(<span class="number">1024</span><span class="operator">,</span> <span class="number">768</span><span class="operator">,</span> maxTextureSize); GraphicsView view; view<span class="operator">.</span>setViewport(widget); view<span class="operator">.</span>setViewportUpdateMode(<span class="type"><a href="qgraphicsview.html">QGraphicsView</a></span><span class="operator">::</span>FullViewportUpdate); view<span class="operator">.</span>setScene(<span class="operator">&</span>scene); view<span class="operator">.</span>show(); <span class="keyword">return</span> app<span class="operator">.</span>exec(); }</pre> </div> <!-- @@@demos/boxes/main.cpp --> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2015 The Qt Company Ltd. 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