1 /*
2 * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
3 * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
14 *
15 * You should have received a copy of the GNU Library General Public License
16 * along with this library; see the file COPYING.LIB. If not, write to
17 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
19 *
20 */
21
22 #include "config.h"
23 #include "platform/transforms/RotateTransformOperation.h"
24
25 #include "platform/animation/AnimationUtilities.h"
26 #include "platform/geometry/FloatPoint3D.h"
27 #include "wtf/MathExtras.h"
28 #include <algorithm>
29
30 namespace blink {
31
32 static const double angleEpsilon = 1e-4;
33
axis() const34 FloatPoint3D RotateTransformOperation::axis() const
35 {
36 return FloatPoint3D(x(), y(), z());
37 }
38
shareSameAxis(const RotateTransformOperation * from,const RotateTransformOperation * to,FloatPoint3D * axis,double * fromAngle,double * toAngle)39 bool RotateTransformOperation::shareSameAxis(const RotateTransformOperation* from, const RotateTransformOperation* to, FloatPoint3D* axis, double* fromAngle, double* toAngle)
40 {
41 *axis = FloatPoint3D(0, 0, 1);
42 *fromAngle = 0;
43 *toAngle = 0;
44
45 if (!from && !to)
46 return true;
47
48 bool fromZero = !from || from->axis().isZero();
49 bool toZero = !to || to->axis().isZero();
50
51 if (fromZero && toZero)
52 return true;
53
54 if (fromZero) {
55 *axis = to->axis();
56 *toAngle = to->angle();
57 return true;
58 }
59
60 if (toZero) {
61 *axis = from->axis();
62 *fromAngle = from->angle();
63 return true;
64 }
65
66 FloatPoint3D fromAxis = from->axis();
67 FloatPoint3D toAxis = to->axis();
68
69 double fromSquared = fromAxis.lengthSquared();
70 double toSquared = toAxis.lengthSquared();
71
72 double dot = fromAxis.dot(toAxis);
73 double error = std::abs(1 - (dot * dot) / (fromSquared * toSquared));
74
75 if (error > angleEpsilon)
76 return false;
77 *axis = from->axis();
78 *fromAngle = from->angle();
79 *toAngle = to->angle();
80 return true;
81 }
82
blend(const TransformOperation * from,double progress,bool blendToIdentity)83 PassRefPtr<TransformOperation> RotateTransformOperation::blend(const TransformOperation* from, double progress, bool blendToIdentity)
84 {
85 if (from && !from->isSameType(*this))
86 return this;
87
88 if (blendToIdentity)
89 return RotateTransformOperation::create(m_x, m_y, m_z, m_angle - m_angle * progress, m_type);
90
91 const RotateTransformOperation* fromOp = static_cast<const RotateTransformOperation*>(from);
92
93 // Optimize for single axis rotation
94 if (!fromOp || (fromOp->m_x == 0 && fromOp->m_y == 0 && fromOp->m_z == 1) ||
95 (fromOp->m_x == 0 && fromOp->m_y == 1 && fromOp->m_z == 0) ||
96 (fromOp->m_x == 1 && fromOp->m_y == 0 && fromOp->m_z == 0)) {
97 double fromAngle = fromOp ? fromOp->m_angle : 0;
98 return RotateTransformOperation::create(fromOp ? fromOp->m_x : m_x,
99 fromOp ? fromOp->m_y : m_y,
100 fromOp ? fromOp->m_z : m_z,
101 blink::blend(fromAngle, m_angle, progress), m_type);
102 }
103 double fromAngle;
104 double toAngle;
105 FloatPoint3D axis;
106
107 if (shareSameAxis(fromOp, this, &axis, &fromAngle, &toAngle))
108 return RotateTransformOperation::create(axis.x(), axis.y(), axis.z(), blink::blend(fromAngle, toAngle, progress), m_type);
109
110 const RotateTransformOperation* toOp = this;
111
112 // Create the 2 rotation matrices
113 TransformationMatrix fromT;
114 TransformationMatrix toT;
115 fromT.rotate3d((fromOp ? fromOp->m_x : 0),
116 (fromOp ? fromOp->m_y : 0),
117 (fromOp ? fromOp->m_z : 1),
118 (fromOp ? fromOp->m_angle : 0));
119
120 toT.rotate3d((toOp ? toOp->m_x : 0),
121 (toOp ? toOp->m_y : 0),
122 (toOp ? toOp->m_z : 1),
123 (toOp ? toOp->m_angle : 0));
124
125 // Blend them
126 toT.blend(fromT, progress);
127
128 // Extract the result as a quaternion
129 TransformationMatrix::DecomposedType decomp;
130 toT.decompose(decomp);
131
132 // Convert that to Axis/Angle form
133 double x = -decomp.quaternionX;
134 double y = -decomp.quaternionY;
135 double z = -decomp.quaternionZ;
136 double length = std::sqrt(x * x + y * y + z * z);
137 double angle = 0;
138
139 if (length > 0.00001) {
140 x /= length;
141 y /= length;
142 z /= length;
143 angle = rad2deg(std::acos(decomp.quaternionW) * 2);
144 } else {
145 x = 0;
146 y = 0;
147 z = 1;
148 }
149 return RotateTransformOperation::create(x, y, z, angle, Rotate3D);
150 }
151
canBlendWith(const TransformOperation & other) const152 bool RotateTransformOperation::canBlendWith(const TransformOperation& other) const
153 {
154 return other.isSameType(*this);
155 }
156
157 } // namespace blink
158