|
1 /**************************************************************************** |
|
2 ** |
|
3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). |
|
4 ** All rights reserved. |
|
5 ** Contact: Nokia Corporation (qt-info@nokia.com) |
|
6 ** |
|
7 ** This file is part of the demonstration applications of the Qt Toolkit. |
|
8 ** |
|
9 ** $QT_BEGIN_LICENSE:LGPL$ |
|
10 ** No Commercial Usage |
|
11 ** This file contains pre-release code and may not be distributed. |
|
12 ** You may use this file in accordance with the terms and conditions |
|
13 ** contained in the Technology Preview License Agreement accompanying |
|
14 ** this package. |
|
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. |
|
23 ** |
|
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. |
|
27 ** |
|
28 ** If you have questions regarding the use of this file, please contact |
|
29 ** Nokia at qt-info@nokia.com. |
|
30 ** |
|
31 ** |
|
32 ** |
|
33 ** |
|
34 ** |
|
35 ** |
|
36 ** |
|
37 ** |
|
38 ** $QT_END_LICENSE$ |
|
39 ** |
|
40 ****************************************************************************/ |
|
41 |
|
42 #include "trackball.h" |
|
43 #include "scene.h" |
|
44 |
|
45 //============================================================================// |
|
46 // TrackBall // |
|
47 //============================================================================// |
|
48 |
|
49 TrackBall::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 |
|
60 TrackBall::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 |
|
71 void 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 |
|
80 void 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.rotateVector(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); |
|
111 if (sqrZ > 0) |
|
112 currentPos3D.setZ(sqrt(sqrZ)); |
|
113 else |
|
114 currentPos3D.normalize(); |
|
115 |
|
116 m_axis = QVector3D::crossProduct(lastPos3D, currentPos3D); |
|
117 float angle = 180 / PI * asin(sqrt(QVector3D::dotProduct(m_axis, m_axis))); |
|
118 |
|
119 m_angularVelocity = angle / msecs; |
|
120 m_axis.normalize(); |
|
121 m_axis = transformation.rotateVector(m_axis); |
|
122 m_rotation = QQuaternion::fromAxisAndAngle(m_axis, angle) * m_rotation; |
|
123 } |
|
124 break; |
|
125 } |
|
126 |
|
127 |
|
128 m_lastPos = p; |
|
129 m_lastTime = currentTime; |
|
130 } |
|
131 |
|
132 void TrackBall::release(const QPointF& p, const QQuaternion &transformation) |
|
133 { |
|
134 // Calling move() caused the rotation to stop if the framerate was too low. |
|
135 move(p, transformation); |
|
136 m_pressed = false; |
|
137 } |
|
138 |
|
139 void TrackBall::start() |
|
140 { |
|
141 m_lastTime = QTime::currentTime(); |
|
142 m_paused = false; |
|
143 } |
|
144 |
|
145 void TrackBall::stop() |
|
146 { |
|
147 m_rotation = rotation(); |
|
148 m_paused = true; |
|
149 } |
|
150 |
|
151 QQuaternion TrackBall::rotation() const |
|
152 { |
|
153 if (m_paused || m_pressed) |
|
154 return m_rotation; |
|
155 |
|
156 QTime currentTime = QTime::currentTime(); |
|
157 float angle = m_angularVelocity * m_lastTime.msecsTo(currentTime); |
|
158 return QQuaternion::fromAxisAndAngle(m_axis, angle) * m_rotation; |
|
159 } |
|
160 |