source: trunk/demos/boxes/trackball.cpp@ 683

Last change on this file since 683 was 651, checked in by Dmitry A. Kuminov, 16 years ago

trunk: Merged in qt 4.6.2 sources.
File size: 5.2 KB
Line 
1/****************************************************************************
2**
3** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
4** All rights reserved.
5** Contact: Nokia Corporation ([email protected])
6**
7** This file is part of the demonstration applications of the Qt Toolkit.
8**
9** $QT_BEGIN_LICENSE:LGPL$
10** Commercial Usage
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12** accordance with the Qt Commercial License Agreement provided with the
13** Software or, alternatively, in accordance with the terms contained in
14** a written agreement between you and Nokia.
15**
16** GNU Lesser General Public License Usage
17** Alternatively, this file may be used under the terms of the GNU Lesser
18** General Public License version 2.1 as published by the Free Software
19** Foundation and appearing in the file LICENSE.LGPL included in the
20** packaging of this file. Please review the following information to
21** ensure the GNU Lesser General Public License version 2.1 requirements
22** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
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24** In addition, as a special exception, Nokia gives you certain additional
25** rights. These rights are described in the Nokia Qt LGPL Exception
26** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
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28** GNU General Public License Usage
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30** General Public License version 3.0 as published by the Free Software
31** Foundation and appearing in the file LICENSE.GPL included in the
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33** ensure the GNU General Public License version 3.0 requirements will be
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40****************************************************************************/
41
42#include "trackball.h"
43#include "scene.h"
44
45//============================================================================//
46// TrackBall //
47//============================================================================//
48
49TrackBall::TrackBall(TrackMode mode)
50 : m_angularVelocity(0)
51 , m_paused(false)
52 , m_pressed(false)
53 , m_mode(mode)
54{
55 m_axis = QVector3D(0, 1, 0);
56 m_rotation = QQuaternion();
57 m_lastTime = QTime::currentTime();
58}
59
60TrackBall::TrackBall(float angularVelocity, const QVector3D& axis, TrackMode mode)
61 : m_axis(axis)
62 , m_angularVelocity(angularVelocity)
63 , m_paused(false)
64 , m_pressed(false)
65 , m_mode(mode)
66{
67 m_rotation = QQuaternion();
68 m_lastTime = QTime::currentTime();
69}
70
71void TrackBall::push(const QPointF& p, const QQuaternion &)
72{
73 m_rotation = rotation();
74 m_pressed = true;
75 m_lastTime = QTime::currentTime();
76 m_lastPos = p;
77 m_angularVelocity = 0.0f;
78}
79
80void TrackBall::move(const QPointF& p, const QQuaternion &transformation)
81{
82 if (!m_pressed)
83 return;
84
85 QTime currentTime = QTime::currentTime();
86 int msecs = m_lastTime.msecsTo(currentTime);
87 if (msecs <= 20)
88 return;
89
90 switch (m_mode) {
91 case Plane:
92 {
93 QLineF delta(m_lastPos, p);
94 m_angularVelocity = 180*delta.length() / (PI*msecs);
95 m_axis = QVector3D(-delta.dy(), delta.dx(), 0.0f).normalized();
96 m_axis = transformation.rotatedVector(m_axis);
97 m_rotation = QQuaternion::fromAxisAndAngle(m_axis, 180 / PI * delta.length()) * m_rotation;
98 }
99 break;
100 case Sphere:
101 {
102 QVector3D lastPos3D = QVector3D(m_lastPos.x(), m_lastPos.y(), 0.0f);
103 float sqrZ = 1 - QVector3D::dotProduct(lastPos3D, lastPos3D);
104 if (sqrZ > 0)
105 lastPos3D.setZ(sqrt(sqrZ));
106 else
107 lastPos3D.normalize();
108
109 QVector3D currentPos3D = QVector3D(p.x(), p.y(), 0.0f);
110 sqrZ = 1 - QVector3D::dotProduct(currentPos3D, currentPos3D);