<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>main.cpp Example File | Qt GUI 5.12.2</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtgui-index.html">Qt GUI</a></td><td ><a href="qtgui-openglwindow-example.html">OpenGL Window Example</a></td><td >main.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtgui-index.html">Qt 5.12.2 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"><div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">main.cpp Example File</h1> <span class="subtitle">openglwindow/main.cpp</span> <!-- $$$openglwindow/main.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the documentation of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** 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 https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, you may use this file under the terms of the BSD license ** as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of The Qt Company Ltd nor the names of its ** contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include "openglwindow.h"</span> <span class="preprocessor">#include <QtGui/QGuiApplication></span> <span class="preprocessor">#include <QtGui/QMatrix4x4></span> <span class="preprocessor">#include <QtGui/QOpenGLShaderProgram></span> <span class="preprocessor">#include <QtGui/QScreen></span> <span class="preprocessor">#include <QtCore/qmath.h></span> <span class="keyword">class</span> TriangleWindow : <span class="keyword">public</span> OpenGLWindow { <span class="keyword">public</span>: TriangleWindow(); <span class="type">void</span> initialize() override; <span class="type">void</span> render() override; <span class="keyword">private</span>: GLuint m_posAttr; GLuint m_colAttr; GLuint m_matrixUniform; <span class="type"><a href="qopenglshaderprogram.html">QOpenGLShaderProgram</a></span> <span class="operator">*</span>m_program; <span class="type">int</span> m_frame; }; TriangleWindow<span class="operator">::</span>TriangleWindow() : m_program(<span class="number">0</span>) <span class="operator">,</span> m_frame(<span class="number">0</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="qguiapplication.html">QGuiApplication</a></span> app(argc<span class="operator">,</span> argv); <span class="type"><a href="qsurfaceformat.html">QSurfaceFormat</a></span> format; format<span class="operator">.</span>setSamples(<span class="number">16</span>); TriangleWindow window; window<span class="operator">.</span>setFormat(format); window<span class="operator">.</span>resize(<span class="number">640</span><span class="operator">,</span> <span class="number">480</span>); window<span class="operator">.</span>show(); window<span class="operator">.</span>setAnimating(<span class="keyword">true</span>); <span class="keyword">return</span> app<span class="operator">.</span>exec(); } <span class="keyword">static</span> <span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span>vertexShaderSource <span class="operator">=</span> <span class="string">"attribute highp vec4 posAttr;\n"</span> <span class="string">"attribute lowp vec4 colAttr;\n"</span> <span class="string">"varying lowp vec4 col;\n"</span> <span class="string">"uniform highp mat4 matrix;\n"</span> <span class="string">"void main() {\n"</span> <span class="string">" col = colAttr;\n"</span> <span class="string">" gl_Position = matrix * posAttr;\n"</span> <span class="string">"}\n"</span>; <span class="keyword">static</span> <span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span>fragmentShaderSource <span class="operator">=</span> <span class="string">"varying lowp vec4 col;\n"</span> <span class="string">"void main() {\n"</span> <span class="string">" gl_FragColor = col;\n"</span> <span class="string">"}\n"</span>; <span class="type">void</span> TriangleWindow<span class="operator">::</span>initialize() { m_program <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qopenglshaderprogram.html">QOpenGLShaderProgram</a></span>(<span class="keyword">this</span>); m_program<span class="operator">-</span><span class="operator">></span>addShaderFromSourceCode(<span class="type"><a href="qopenglshader.html">QOpenGLShader</a></span><span class="operator">::</span>Vertex<span class="operator">,</span> vertexShaderSource); m_program<span class="operator">-</span><span class="operator">></span>addShaderFromSourceCode(<span class="type"><a href="qopenglshader.html">QOpenGLShader</a></span><span class="operator">::</span>Fragment<span class="operator">,</span> fragmentShaderSource); m_program<span class="operator">-</span><span class="operator">></span>link(); m_posAttr <span class="operator">=</span> m_program<span class="operator">-</span><span class="operator">></span>attributeLocation(<span class="string">"posAttr"</span>); m_colAttr <span class="operator">=</span> m_program<span class="operator">-</span><span class="operator">></span>attributeLocation(<span class="string">"colAttr"</span>); m_matrixUniform <span class="operator">=</span> m_program<span class="operator">-</span><span class="operator">></span>uniformLocation(<span class="string">"matrix"</span>); } <span class="type">void</span> TriangleWindow<span class="operator">::</span>render() { <span class="keyword">const</span> <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> retinaScale <span class="operator">=</span> devicePixelRatio(); glViewport(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> width() <span class="operator">*</span> retinaScale<span class="operator">,</span> height() <span class="operator">*</span> retinaScale); glClear(GL_COLOR_BUFFER_BIT); m_program<span class="operator">-</span><span class="operator">></span>bind(); QMatrix4x4 matrix; matrix<span class="operator">.</span>perspective(<span class="number">60.0f</span><span class="operator">,</span> <span class="number">4.0f</span><span class="operator">/</span><span class="number">3.0f</span><span class="operator">,</span> <span class="number">0.1f</span><span class="operator">,</span> <span class="number">100.0f</span>); matrix<span class="operator">.</span>translate(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="operator">-</span><span class="number">2</span>); matrix<span class="operator">.</span>rotate(<span class="number">100.0f</span> <span class="operator">*</span> m_frame <span class="operator">/</span> screen()<span class="operator">-</span><span class="operator">></span>refreshRate()<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">0</span>); m_program<span class="operator">-</span><span class="operator">></span>setUniformValue(m_matrixUniform<span class="operator">,</span> matrix); GLfloat vertices<span class="operator">[</span><span class="operator">]</span> <span class="operator">=</span> { <span class="number">0.0f</span><span class="operator">,</span> <span class="number">0.707f</span><span class="operator">,</span> <span class="operator">-</span><span class="number">0.5f</span><span class="operator">,</span> <span class="operator">-</span><span class="number">0.5f</span><span class="operator">,</span> <span class="number">0.5f</span><span class="operator">,</span> <span class="operator">-</span><span class="number">0.5f</span> }; GLfloat colors<span class="operator">[</span><span class="operator">]</span> <span class="operator">=</span> { <span class="number">1.0f</span><span class="operator">,</span> <span class="number">0.0f</span><span class="operator">,</span> <span class="number">0.0f</span><span class="operator">,</span> <span class="number">0.0f</span><span class="operator">,</span> <span class="number">1.0f</span><span class="operator">,</span> <span class="number">0.0f</span><span class="operator">,</span> <span class="number">0.0f</span><span class="operator">,</span> <span class="number">0.0f</span><span class="operator">,</span> <span class="number">1.0f</span> }; glVertexAttribPointer(m_posAttr<span class="operator">,</span> <span class="number">2</span><span class="operator">,</span> GL_FLOAT<span class="operator">,</span> GL_FALSE<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> vertices); glVertexAttribPointer(m_colAttr<span class="operator">,</span> <span class="number">3</span><span class="operator">,</span> GL_FLOAT<span class="operator">,</span> GL_FALSE<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> colors); glEnableVertexAttribArray(<span class="number">0</span>); glEnableVertexAttribArray(<span class="number">1</span>); glDrawArrays(GL_TRIANGLES<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">3</span>); glDisableVertexAttribArray(<span class="number">1</span>); glDisableVertexAttribArray(<span class="number">0</span>); m_program<span class="operator">-</span><span class="operator">></span>release(); <span class="operator">+</span><span class="operator">+</span>m_frame; } </pre> </div> <!-- @@@openglwindow/main.cpp --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>