<?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>edge.cpp Example File | Qt Widgets 5.12.6</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="qtwidgets-index.html">Qt Widgets</a></td><td ><a href="qtwidgets-graphicsview-elasticnodes-example.html">Elastic Nodes Example</a></td><td >edge.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtwidgets-index.html">Qt 5.12.6 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">edge.cpp Example File</h1> <span class="subtitle">graphicsview/elasticnodes/edge.cpp</span> <!-- $$$graphicsview/elasticnodes/edge.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 examples 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 "edge.h"</span> <span class="preprocessor">#include "node.h"</span> <span class="preprocessor">#include <qmath.h></span> <span class="preprocessor">#include <QPainter></span> Edge<span class="operator">::</span>Edge(Node <span class="operator">*</span>sourceNode<span class="operator">,</span> Node <span class="operator">*</span>destNode) : arrowSize(<span class="number">10</span>) { setAcceptedMouseButtons(<span class="number">0</span>); source <span class="operator">=</span> sourceNode; dest <span class="operator">=</span> destNode; source<span class="operator">-</span><span class="operator">></span>addEdge(<span class="keyword">this</span>); dest<span class="operator">-</span><span class="operator">></span>addEdge(<span class="keyword">this</span>); adjust(); } Node <span class="operator">*</span>Edge<span class="operator">::</span>sourceNode() <span class="keyword">const</span> { <span class="keyword">return</span> source; } Node <span class="operator">*</span>Edge<span class="operator">::</span>destNode() <span class="keyword">const</span> { <span class="keyword">return</span> dest; } <span class="type">void</span> Edge<span class="operator">::</span>adjust() { <span class="keyword">if</span> (<span class="operator">!</span>source <span class="operator">|</span><span class="operator">|</span> <span class="operator">!</span>dest) <span class="keyword">return</span>; <span class="type"><a href="../qtcore/qlinef.html">QLineF</a></span> line(mapFromItem(source<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">0</span>)<span class="operator">,</span> mapFromItem(dest<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">0</span>)); <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> length <span class="operator">=</span> line<span class="operator">.</span>length(); prepareGeometryChange(); <span class="keyword">if</span> (length <span class="operator">></span> <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span>(<span class="number">20.</span>)) { <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span> edgeOffset((line<span class="operator">.</span>dx() <span class="operator">*</span> <span class="number">10</span>) <span class="operator">/</span> length<span class="operator">,</span> (line<span class="operator">.</span>dy() <span class="operator">*</span> <span class="number">10</span>) <span class="operator">/</span> length); sourcePoint <span class="operator">=</span> line<span class="operator">.</span>p1() <span class="operator">+</span> edgeOffset; destPoint <span class="operator">=</span> line<span class="operator">.</span>p2() <span class="operator">-</span> edgeOffset; } <span class="keyword">else</span> { sourcePoint <span class="operator">=</span> destPoint <span class="operator">=</span> line<span class="operator">.</span>p1(); } } <span class="type"><a href="../qtcore/qrectf.html">QRectF</a></span> Edge<span class="operator">::</span>boundingRect() <span class="keyword">const</span> { <span class="keyword">if</span> (<span class="operator">!</span>source <span class="operator">|</span><span class="operator">|</span> <span class="operator">!</span>dest) <span class="keyword">return</span> <span class="type"><a href="../qtcore/qrectf.html">QRectF</a></span>(); <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> penWidth <span class="operator">=</span> <span class="number">1</span>; <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span> extra <span class="operator">=</span> (penWidth <span class="operator">+</span> arrowSize) <span class="operator">/</span> <span class="number">2.0</span>; <span class="keyword">return</span> <span class="type"><a href="../qtcore/qrectf.html">QRectF</a></span>(sourcePoint<span class="operator">,</span> <span class="type"><a href="../qtcore/qsizef.html">QSizeF</a></span>(destPoint<span class="operator">.</span>x() <span class="operator">-</span> sourcePoint<span class="operator">.</span>x()<span class="operator">,</span> destPoint<span class="operator">.</span>y() <span class="operator">-</span> sourcePoint<span class="operator">.</span>y())) <span class="operator">.</span>normalized() <span class="operator">.</span>adjusted(<span class="operator">-</span>extra<span class="operator">,</span> <span class="operator">-</span>extra<span class="operator">,</span> extra<span class="operator">,</span> extra); } <span class="type">void</span> Edge<span class="operator">::</span>paint(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span> <span class="operator">*</span>painter<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="qstyleoptiongraphicsitem.html">QStyleOptionGraphicsItem</a></span> <span class="operator">*</span><span class="operator">,</span> <span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>) { <span class="keyword">if</span> (<span class="operator">!</span>source <span class="operator">|</span><span class="operator">|</span> <span class="operator">!</span>dest) <span class="keyword">return</span>; <span class="type"><a href="../qtcore/qlinef.html">QLineF</a></span> line(sourcePoint<span class="operator">,</span> destPoint); <span class="keyword">if</span> (<a href="../qtcore/qtglobal.html#qFuzzyCompare">qFuzzyCompare</a>(line<span class="operator">.</span>length()<span class="operator">,</span> <span class="type"><a href="../qtcore/qtglobal.html#qreal-typedef">qreal</a></span>(<span class="number">0.</span>))) <span class="keyword">return</span>; <span class="comment">// Draw the line itself</span> painter<span class="operator">-</span><span class="operator">></span>setPen(<span class="type"><a href="../qtgui/qpen.html">QPen</a></span>(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>black<span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>SolidLine<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>RoundCap<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>RoundJoin)); painter<span class="operator">-</span><span class="operator">></span>drawLine(line); <span class="comment">// Draw the arrows</span> <span class="type">double</span> angle <span class="operator">=</span> std<span class="operator">::</span>atan2(<span class="operator">-</span>line<span class="operator">.</span>dy()<span class="operator">,</span> line<span class="operator">.</span>dx()); <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span> sourceArrowP1 <span class="operator">=</span> sourcePoint <span class="operator">+</span> <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span>(sin(angle <span class="operator">+</span> M_PI <span class="operator">/</span> <span class="number">3</span>) <span class="operator">*</span> arrowSize<span class="operator">,</span> cos(angle <span class="operator">+</span> M_PI <span class="operator">/</span> <span class="number">3</span>) <span class="operator">*</span> arrowSize); <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span> sourceArrowP2 <span class="operator">=</span> sourcePoint <span class="operator">+</span> <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span>(sin(angle <span class="operator">+</span> M_PI <span class="operator">-</span> M_PI <span class="operator">/</span> <span class="number">3</span>) <span class="operator">*</span> arrowSize<span class="operator">,</span> cos(angle <span class="operator">+</span> M_PI <span class="operator">-</span> M_PI <span class="operator">/</span> <span class="number">3</span>) <span class="operator">*</span> arrowSize); <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span> destArrowP1 <span class="operator">=</span> destPoint <span class="operator">+</span> <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span>(sin(angle <span class="operator">-</span> M_PI <span class="operator">/</span> <span class="number">3</span>) <span class="operator">*</span> arrowSize<span class="operator">,</span> cos(angle <span class="operator">-</span> M_PI <span class="operator">/</span> <span class="number">3</span>) <span class="operator">*</span> arrowSize); <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span> destArrowP2 <span class="operator">=</span> destPoint <span class="operator">+</span> <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span>(sin(angle <span class="operator">-</span> M_PI <span class="operator">+</span> M_PI <span class="operator">/</span> <span class="number">3</span>) <span class="operator">*</span> arrowSize<span class="operator">,</span> cos(angle <span class="operator">-</span> M_PI <span class="operator">+</span> M_PI <span class="operator">/</span> <span class="number">3</span>) <span class="operator">*</span> arrowSize); painter<span class="operator">-</span><span class="operator">></span>setBrush(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>black); painter<span class="operator">-</span><span class="operator">></span>drawPolygon(<span class="type"><a href="../qtgui/qpolygonf.html">QPolygonF</a></span>() <span class="operator"><</span><span class="operator"><</span> line<span class="operator">.</span>p1() <span class="operator"><</span><span class="operator"><</span> sourceArrowP1 <span class="operator"><</span><span class="operator"><</span> sourceArrowP2); painter<span class="operator">-</span><span class="operator">></span>drawPolygon(<span class="type"><a href="../qtgui/qpolygonf.html">QPolygonF</a></span>() <span class="operator"><</span><span class="operator"><</span> line<span class="operator">.</span>p2() <span class="operator"><</span><span class="operator"><</span> destArrowP1 <span class="operator"><</span><span class="operator"><</span> destArrowP2); } </pre> </div> <!-- @@@graphicsview/elasticnodes/edge.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>