summaryrefslogtreecommitdiffstats
path: root/examples/quick/quickwidgets/quickwidget/fbitem.cpp
blob: cb3cc976fb01375ccc3b78aaaa03f4aca1dae1a7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** 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."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "fbitem.h"
#include <QtGui/QOpenGLFramebufferObject>
#include <QtGui/QOpenGLContext>
#include <QtGui/QOpenGLFunctions>
#include <QtCore/QDebug>

#if QT_CONFIG(opengl)
class FbRenderer : public QQuickFramebufferObject::Renderer
{
public:
    FbRenderer() : c(0), dir(1) { }

    // The lifetime of the FBO and this class depends on how QQuickWidget
    // manages the scenegraph and context when it comes to showing and hiding
    // the widget. The actual behavior is proven by the debug prints.
    ~FbRenderer() {
        qDebug("FbRenderer destroyed");
    }

    void render() {
        QOpenGLFunctions *f = QOpenGLContext::currentContext()->functions();
        f->glClearColor(c, 0, 0, 1);
        f->glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
        c += 0.01f * dir;
        if (c >= 1.0f || c <= 0.0f)
            dir *= -1;
        update();
    }

    QOpenGLFramebufferObject *createFramebufferObject(const QSize &size) {
        qDebug() << "Creating FBO" << size;
        QOpenGLFramebufferObjectFormat format;
        format.setAttachment(QOpenGLFramebufferObject::CombinedDepthStencil);
        return new QOpenGLFramebufferObject(size, format);
    }

private:
    float c;
    int dir;
};
#endif

QQuickFramebufferObject::Renderer *FbItem::createRenderer() const
{
#if QT_CONFIG(opengl)
    return new FbRenderer;
#else
    return nullptr;
#endif
}