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50
51#include "fbopaintdevice.h"
52
53#include <QOffscreenSurface>
54#include <QOpenGLFunctions>
55
56QFboPaintDevice::QFboPaintDevice(const QSize &size, bool flipped, bool clearOnInit,
57 QOpenGLFramebufferObject::Attachment attachment)
58 : QOpenGLPaintDevice(size)
59{
60 QOpenGLFramebufferObjectFormat format;
61 format.setAttachment(attachment);
62 format.setSamples(4);
63 m_framebufferObject = new QOpenGLFramebufferObject(size, format);
64 QOffscreenSurface *surface = new QOffscreenSurface();
65 surface->create();
66 m_surface = surface;
67 setPaintFlipped(flipped);
68 if (clearOnInit) {
69 m_framebufferObject->bind();
70
71 context()->functions()->glClearColor(red: 0, green: 0, blue: 0, alpha: 0);
72 context()->functions()->glClear(GL_COLOR_BUFFER_BIT);
73 }
74}
75
76QFboPaintDevice::~QFboPaintDevice()
77{
78 delete m_framebufferObject;
79 delete m_surface;
80}
81
82void QFboPaintDevice::ensureActiveTarget()
83{
84 if (QOpenGLContext::currentContext() != context())
85 context()->makeCurrent(surface: m_surface);
86
87 m_framebufferObject->bind();
88}
89
90GLuint QFboPaintDevice::takeTexture()
91{
92 // We have multisamples so we can't just forward takeTexture().
93 QOpenGLFramebufferObject resolvedFbo(m_framebufferObject->size(), m_framebufferObject->attachment());
94 QOpenGLFramebufferObject::blitFramebuffer(target: &resolvedFbo, source: m_framebufferObject);
95 return resolvedFbo.takeTexture();
96}
97
98QImage QFboPaintDevice::toImage() const
99{
100 QOpenGLContext *currentContext = QOpenGLContext::currentContext();
101 QSurface *currentSurface = currentContext ? currentContext->surface() : nullptr;
102
103 context()->makeCurrent(surface: m_surface);
104
105 QImage image = m_framebufferObject->toImage(flipped: !paintFlipped());
106
107 if (currentContext)
108 currentContext->makeCurrent(surface: currentSurface);
109 else
110 context()->doneCurrent();
111
112 return image;
113}
114

source code of qtbase/examples/widgets/painting/shared/fbopaintdevice.cpp