<?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>datasource.cpp Example File | Qt Data Visualization 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="qtdatavisualization-index.html">Qt Data Visualization</a></td><td ><a href="qtdatavisualization-qmloscilloscope-example.html">Qt Quick 2 Oscilloscope Example</a></td><td >datasource.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtdatavisualization-index.html">Qt Data Visualization | Commercial or GPLv3</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">datasource.cpp Example File</h1> <span class="subtitle">qmloscilloscope/datasource.cpp</span> <!-- $$$qmloscilloscope/datasource.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 Qt Data Visualization module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:GPL$ ** 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. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 3 or (at your option) any later version ** approved by the KDE Free Qt Foundation. The licenses are as published by ** the Free Software Foundation and appearing in the file LICENSE.GPL3 ** included in the packaging of this file. Please review the following ** information to ensure the GNU General Public License requirements will ** be met: https://www.gnu.org/licenses/gpl-3.0.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include "datasource.h"</span> <span class="preprocessor">#include <QtCore/qmath.h></span> <span class="preprocessor">#include <QtCore/qrandom.h></span> <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="type">QtDataVisualization</span>; Q_DECLARE_METATYPE(QSurface3DSeries <span class="operator">*</span>) DataSource<span class="operator">::</span>DataSource(<span class="type">QObject</span> <span class="operator">*</span>parent) : <span class="type">QObject</span>(parent)<span class="operator">,</span> m_index(<span class="operator">-</span><span class="number">1</span>)<span class="operator">,</span> m_resetArray(nullptr) { qRegisterMetaType<span class="operator"><</span>QSurface3DSeries <span class="operator">*</span><span class="operator">></span>(); } DataSource<span class="operator">::</span><span class="operator">~</span>DataSource() { clearData(); } <span class="type">void</span> DataSource<span class="operator">::</span>generateData(<span class="type">int</span> cacheCount<span class="operator">,</span> <span class="type">int</span> rowCount<span class="operator">,</span> <span class="type">int</span> columnCount<span class="operator">,</span> <span class="type">float</span> xMin<span class="operator">,</span> <span class="type">float</span> xMax<span class="operator">,</span> <span class="type">float</span> yMin<span class="operator">,</span> <span class="type">float</span> yMax<span class="operator">,</span> <span class="type">float</span> zMin<span class="operator">,</span> <span class="type">float</span> zMax) { <span class="keyword">if</span> (<span class="operator">!</span>cacheCount <span class="operator">|</span><span class="operator">|</span> <span class="operator">!</span>rowCount <span class="operator">|</span><span class="operator">|</span> <span class="operator">!</span>columnCount) <span class="keyword">return</span>; clearData(); <span class="comment">// Re-create the cache array</span> m_data<span class="operator">.</span>resize(cacheCount); <span class="keyword">for</span> (<span class="type">int</span> i(<span class="number">0</span>); i <span class="operator"><</span> cacheCount; i<span class="operator">+</span><span class="operator">+</span>) { <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataArray-typedef">QSurfaceDataArray</a></span> <span class="operator">&</span>array <span class="operator">=</span> m_data<span class="operator">[</span>i<span class="operator">]</span>; array<span class="operator">.</span>reserve(rowCount); <span class="keyword">for</span> (<span class="type">int</span> j(<span class="number">0</span>); j <span class="operator"><</span> rowCount; j<span class="operator">+</span><span class="operator">+</span>) array<span class="operator">.</span>append(<span class="keyword">new</span> <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataRow-typedef">QSurfaceDataRow</a></span>(columnCount)); } <span class="type">float</span> xRange <span class="operator">=</span> xMax <span class="operator">-</span> xMin; <span class="type">float</span> yRange <span class="operator">=</span> yMax <span class="operator">-</span> yMin; <span class="type">float</span> zRange <span class="operator">=</span> zMax <span class="operator">-</span> zMin; <span class="type">int</span> cacheIndexStep <span class="operator">=</span> columnCount <span class="operator">/</span> cacheCount; <span class="type">float</span> cacheStep <span class="operator">=</span> <span class="type">float</span>(cacheIndexStep) <span class="operator">*</span> xRange <span class="operator">/</span> <span class="type">float</span>(columnCount); <span class="comment">// Populate caches</span> <span class="keyword">for</span> (<span class="type">int</span> i(<span class="number">0</span>); i <span class="operator"><</span> cacheCount; i<span class="operator">+</span><span class="operator">+</span>) { <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataArray-typedef">QSurfaceDataArray</a></span> <span class="operator">&</span>cache <span class="operator">=</span> m_data<span class="operator">[</span>i<span class="operator">]</span>; <span class="type">float</span> cacheXAdjustment <span class="operator">=</span> cacheStep <span class="operator">*</span> i; <span class="type">float</span> cacheIndexAdjustment <span class="operator">=</span> cacheIndexStep <span class="operator">*</span> i; <span class="keyword">for</span> (<span class="type">int</span> j(<span class="number">0</span>); j <span class="operator"><</span> rowCount; j<span class="operator">+</span><span class="operator">+</span>) { <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataRow-typedef">QSurfaceDataRow</a></span> <span class="operator">&</span>row <span class="operator">=</span> <span class="operator">*</span>(cache<span class="operator">[</span>j<span class="operator">]</span>); <span class="type">float</span> rowMod <span class="operator">=</span> (<span class="type">float</span>(j)) <span class="operator">/</span> <span class="type">float</span>(rowCount); <span class="type">float</span> yRangeMod <span class="operator">=</span> yRange <span class="operator">*</span> rowMod; <span class="type">float</span> zRangeMod <span class="operator">=</span> zRange <span class="operator">*</span> rowMod; <span class="type">float</span> z <span class="operator">=</span> zRangeMod <span class="operator">+</span> zMin; <span class="type">qreal</span> rowColWaveAngleMul <span class="operator">=</span> M_PI <span class="operator">*</span> M_PI <span class="operator">*</span> rowMod; <span class="type">float</span> rowColWaveMul <span class="operator">=</span> yRangeMod <span class="operator">*</span> <span class="number">0.2f</span>; <span class="keyword">for</span> (<span class="type">int</span> k(<span class="number">0</span>); k <span class="operator"><</span> columnCount; k<span class="operator">+</span><span class="operator">+</span>) { <span class="type">float</span> colMod <span class="operator">=</span> (<span class="type">float</span>(k)) <span class="operator">/</span> <span class="type">float</span>(columnCount); <span class="type">float</span> xRangeMod <span class="operator">=</span> xRange <span class="operator">*</span> colMod; <span class="type">float</span> x <span class="operator">=</span> xRangeMod <span class="operator">+</span> xMin <span class="operator">+</span> cacheXAdjustment; <span class="type">float</span> colWave <span class="operator">=</span> <span class="type">float</span>(qSin((<span class="number">2.0</span> <span class="operator">*</span> M_PI <span class="operator">*</span> colMod) <span class="operator">-</span> (<span class="number">1.0</span> <span class="operator">/</span> <span class="number">2.0</span> <span class="operator">*</span> M_PI)) <span class="operator">+</span> <span class="number">1.0</span>); <span class="type">float</span> y <span class="operator">=</span> (colWave <span class="operator">*</span> ((<span class="type">float</span>(qSin(rowColWaveAngleMul <span class="operator">*</span> colMod) <span class="operator">+</span> <span class="number">1.0</span>)))) <span class="operator">*</span> rowColWaveMul <span class="operator">+</span> <span class="type">QRandomGenerator</span><span class="operator">::</span>global()<span class="operator">-</span><span class="operator">></span>bounded(<span class="number">0.15f</span>) <span class="operator">*</span> yRangeMod; <span class="type">int</span> index <span class="operator">=</span> k <span class="operator">+</span> cacheIndexAdjustment; <span class="keyword">if</span> (index <span class="operator">></span><span class="operator">=</span> columnCount) { <span class="comment">// Wrap over</span> index <span class="operator">-</span><span class="operator">=</span> columnCount; x <span class="operator">-</span><span class="operator">=</span> xRange; } row<span class="operator">[</span>index<span class="operator">]</span> <span class="operator">=</span> QVector3D(x<span class="operator">,</span> y<span class="operator">,</span> z); } } } } <span class="type">void</span> DataSource<span class="operator">::</span>update(QSurface3DSeries <span class="operator">*</span>series) { <span class="keyword">if</span> (series <span class="operator">&</span><span class="operator">&</span> m_data<span class="operator">.</span>size()) { <span class="comment">// Each iteration uses data from a different cached array</span> m_index<span class="operator">+</span><span class="operator">+</span>; <span class="keyword">if</span> (m_index <span class="operator">></span> m_data<span class="operator">.</span>count() <span class="operator">-</span> <span class="number">1</span>) m_index <span class="operator">=</span> <span class="number">0</span>; <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataArray-typedef">QSurfaceDataArray</a></span> array <span class="operator">=</span> m_data<span class="operator">.</span>at(m_index); <span class="type">int</span> newRowCount <span class="operator">=</span> array<span class="operator">.</span>size(); <span class="type">int</span> newColumnCount <span class="operator">=</span> array<span class="operator">.</span>at(<span class="number">0</span>)<span class="operator">-</span><span class="operator">></span>size(); <span class="comment">// If the first time or the dimensions of the cache array have changed,</span> <span class="comment">// reconstruct the reset array</span> <span class="keyword">if</span> (<span class="operator">!</span>m_resetArray <span class="operator">|</span><span class="operator">|</span> series<span class="operator">-</span><span class="operator">></span>dataProxy()<span class="operator">-</span><span class="operator">></span>rowCount() <span class="operator">!</span><span class="operator">=</span> newRowCount <span class="operator">|</span><span class="operator">|</span> series<span class="operator">-</span><span class="operator">></span>dataProxy()<span class="operator">-</span><span class="operator">></span>columnCount() <span class="operator">!</span><span class="operator">=</span> newColumnCount) { m_resetArray <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataArray-typedef">QSurfaceDataArray</a></span>(); m_resetArray<span class="operator">-</span><span class="operator">></span>reserve(newRowCount); <span class="keyword">for</span> (<span class="type">int</span> i(<span class="number">0</span>); i <span class="operator"><</span> newRowCount; i<span class="operator">+</span><span class="operator">+</span>) m_resetArray<span class="operator">-</span><span class="operator">></span>append(<span class="keyword">new</span> <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataRow-typedef">QSurfaceDataRow</a></span>(newColumnCount)); } <span class="comment">// Copy items from our cache to the reset array</span> <span class="keyword">for</span> (<span class="type">int</span> i(<span class="number">0</span>); i <span class="operator"><</span> newRowCount; i<span class="operator">+</span><span class="operator">+</span>) { <span class="keyword">const</span> <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataRow-typedef">QSurfaceDataRow</a></span> <span class="operator">&</span>sourceRow <span class="operator">=</span> <span class="operator">*</span>(array<span class="operator">.</span>at(i)); <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataRow-typedef">QSurfaceDataRow</a></span> <span class="operator">&</span>row <span class="operator">=</span> <span class="operator">*</span>(<span class="operator">*</span>m_resetArray)<span class="operator">[</span>i<span class="operator">]</span>; <span class="keyword">for</span> (<span class="type">int</span> j(<span class="number">0</span>); j <span class="operator"><</span> newColumnCount; j<span class="operator">+</span><span class="operator">+</span>) row<span class="operator">[</span>j<span class="operator">]</span><span class="operator">.</span>setPosition(sourceRow<span class="operator">.</span>at(j)<span class="operator">.</span>position()); } <span class="comment">// Notify the proxy that data has changed</span> series<span class="operator">-</span><span class="operator">></span>dataProxy()<span class="operator">-</span><span class="operator">></span>resetArray(m_resetArray); } } <span class="type">void</span> DataSource<span class="operator">::</span>clearData() { <span class="keyword">for</span> (<span class="type">int</span> i(<span class="number">0</span>); i <span class="operator"><</span> m_data<span class="operator">.</span>size(); i<span class="operator">+</span><span class="operator">+</span>) { <span class="type"><a href="qsurfacedataproxy.html#QSurfaceDataArray-typedef">QSurfaceDataArray</a></span> <span class="operator">&</span>array <span class="operator">=</span> m_data<span class="operator">[</span>i<span class="operator">]</span>; <span class="keyword">for</span> (<span class="type">int</span> j(<span class="number">0</span>); j <span class="operator"><</span> array<span class="operator">.</span>size(); j<span class="operator">+</span><span class="operator">+</span>) <span class="keyword">delete</span> array<span class="operator">[</span>j<span class="operator">]</span>; array<span class="operator">.</span>clear(); } } </pre> </div> <!-- @@@qmloscilloscope/datasource.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>