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50
51#include "openglwindow.h"
52
53#include <QOpenGLContext>
54#include <QOpenGLPaintDevice>
55#include <QPainter>
56
57//! [1]
58OpenGLWindow::OpenGLWindow(QWindow *parent)
59 : QWindow(parent)
60{
61 setSurfaceType(QWindow::OpenGLSurface);
62}
63//! [1]
64
65OpenGLWindow::~OpenGLWindow()
66{
67 delete m_device;
68}
69//! [2]
70void OpenGLWindow::render(QPainter *painter)
71{
72 Q_UNUSED(painter);
73}
74
75void OpenGLWindow::initialize()
76{
77}
78
79void OpenGLWindow::render()
80{
81 if (!m_device)
82 m_device = new QOpenGLPaintDevice;
83
84 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
85
86 m_device->setSize(size() * devicePixelRatio());
87 m_device->setDevicePixelRatio(devicePixelRatio());
88
89 QPainter painter(m_device);
90 render(painter: &painter);
91}
92//! [2]
93
94//! [3]
95void OpenGLWindow::renderLater()
96{
97 requestUpdate();
98}
99
100bool OpenGLWindow::event(QEvent *event)
101{
102 switch (event->type()) {
103 case QEvent::UpdateRequest:
104 renderNow();
105 return true;
106 default:
107 return QWindow::event(event);
108 }
109}
110
111void OpenGLWindow::exposeEvent(QExposeEvent *event)
112{
113 Q_UNUSED(event);
114
115 if (isExposed())
116 renderNow();
117}
118//! [3]
119
120//! [4]
121void OpenGLWindow::renderNow()
122{
123 if (!isExposed())
124 return;
125
126 bool needsInitialize = false;
127
128 if (!m_context) {
129 m_context = new QOpenGLContext(this);
130 m_context->setFormat(requestedFormat());
131 m_context->create();
132
133 needsInitialize = true;
134 }
135
136 m_context->makeCurrent(surface: this);
137
138 if (needsInitialize) {
139 initializeOpenGLFunctions();
140 initialize();
141 }
142
143 render();
144
145 m_context->swapBuffers(surface: this);
146
147 if (m_animating)
148 renderLater();
149}
150//! [4]
151
152//! [5]
153void OpenGLWindow::setAnimating(bool animating)
154{
155 m_animating = animating;
156
157 if (animating)
158 renderLater();
159}
160//! [5]
161
162

source code of qtbase/examples/gui/openglwindow/openglwindow.cpp