summaryrefslogtreecommitdiff
path: root/examples/opengl/samplebuffers/glwidget.cpp
blob: e695f75cb54641f12400266b06cee9835f1315bc (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
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "glwidget.h"
#include <math.h>

#ifndef GL_MULTISAMPLE
#define GL_MULTISAMPLE  0x809D
#endif

GLWidget::GLWidget(QWidget *parent)
    : QGLWidget(QGLFormat(QGL::SampleBuffers), parent)
{
    startTimer(40);
    setWindowTitle(tr("Sample Buffers"));
}

void GLWidget::initializeGL()
{
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(-.5, .5, .5, -.5, -1000, 1000);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glClearColor(1.0f, 1.0f, 1.0f, 1.0f);

    makeObject();
}

void GLWidget::resizeGL(int w, int h)
{
    glViewport(0, 0, w, h);
}

void GLWidget::paintGL()
{
    static float rot = 0.0;
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    glEnable(GL_MULTISAMPLE);
    glTranslatef(-0.25f, -0.10f, 0.0f);
    glScalef(0.75f, 1.15f, 0.0f);
    glRotatef(rot, 0.0f, 0.f, 1.0f);
    glCallList(list);
    glPopMatrix();

    glPushMatrix();
    glDisable(GL_MULTISAMPLE);
    glTranslatef(0.25f, -0.10f, 0.0f);
    glScalef(0.75f, 1.15f, 0.0f);
    glRotatef(rot, 0.0f, 0.0f, 1.0f);
    glCallList(list);
    glPopMatrix();

    rot += 0.2f;

    qglColor(Qt::black);
    renderText(-0.35, 0.4, 0.0, "Multisampling enabled");
    renderText(0.15, 0.4, 0.0, "Multisampling disabled");
}

void GLWidget::timerEvent(QTimerEvent *)
{
    update();
}

void GLWidget::makeObject()
{
    QColor qtGreen(QColor::fromCmykF(0.40, 0.0, 1.0, 0.0));
    const double Pi = 3.14159265358979323846;
    const int NumSectors = 15;
    GLdouble x1 = +0.06;
    GLdouble y1 = -0.14;
    GLdouble x2 = +0.14;
    GLdouble y2 = -0.06;
    GLdouble x3 = +0.08;
    GLdouble y3 = +0.00;
    GLdouble x4 = +0.30;
    GLdouble y4 = +0.22;

    list = glGenLists(1);
    glNewList(list, GL_COMPILE);
    {
        for (int i = 0; i < NumSectors; ++i) {
            double angle1 = (i * 2 * Pi) / NumSectors;
            GLdouble x5 = 0.30 * sin(angle1);
            GLdouble y5 = 0.30 * cos(angle1);
            GLdouble x6 = 0.20 * sin(angle1);
            GLdouble y6 = 0.20 * cos(angle1);

            double angle2 = ((i + 1) * 2 * Pi) / NumSectors;
            GLdouble x7 = 0.20 * sin(angle2);
            GLdouble y7 = 0.20 * cos(angle2);
            GLdouble x8 = 0.30 * sin(angle2);
            GLdouble y8 = 0.30 * cos(angle2);

            qglColor(qtGreen);
            quad(GL_QUADS, x5, y5, x6, y6, x7, y7, x8, y8);
            qglColor(Qt::black);
            quad(GL_LINE_LOOP, x5, y5, x6, y6, x7, y7, x8, y8);
        }

        qglColor(qtGreen);
        quad(GL_QUADS, x1, y1, x2, y2, y2, x2, y1, x1);
        quad(GL_QUADS, x3, y3, x4, y4, y4, x4, y3, x3);

        qglColor(Qt::black);
        quad(GL_LINE_LOOP, x1, y1, x2, y2, y2, x2, y1, x1);
        quad(GL_LINE_LOOP, x3, y3, x4, y4, y4, x4, y3, x3);
    }
    glEndList();
}

void GLWidget::quad(GLenum primitive, GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2,
                    GLdouble x3, GLdouble y3, GLdouble x4, GLdouble y4)
{
    glBegin(primitive);
    {
        glVertex2d(x1, y1);
        glVertex2d(x2, y2);
        glVertex2d(x3, y3);
        glVertex2d(x4, y4);
    }
    glEnd();
}