1 /* 2 * Copyright (C) 1999 Antti Koivisto (koivisto (at) 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 using namespace std; 31 32 namespace WebCore { 33 34 static const double angleEpsilon = 1e-4; 35 36 FloatPoint3D RotateTransformOperation::axis() const 37 { 38 return FloatPoint3D(x(), y(), z()); 39 } 40 41 bool RotateTransformOperation::shareSameAxis(const RotateTransformOperation* from, const RotateTransformOperation* to, FloatPoint3D* axis, double* fromAngle, double* toAngle) 42 { 43 *axis = FloatPoint3D(0, 0, 1); 44 *fromAngle = 0; 45 *toAngle = 0; 46 47 if (!from && !to) 48 return true; 49 50 bool fromZero = !from || from->axis().isZero(); 51 bool toZero = !to || to->axis().isZero(); 52 53 if (fromZero && toZero) 54 return true; 55 56 if (fromZero) { 57 *axis = to->axis(); 58 *toAngle = to->angle(); 59 return true; 60 } 61 62 if (toZero) { 63 *axis = from->axis(); 64 *fromAngle = from->angle(); 65 return true; 66 } 67 68 FloatPoint3D fromAxis = from->axis(); 69 FloatPoint3D toAxis = to->axis(); 70 71 double fromSquared = fromAxis.lengthSquared(); 72 double toSquared = toAxis.lengthSquared(); 73 74 double dot = fromAxis.dot(toAxis); 75 double error = std::abs(1 - (dot * dot) / (fromSquared * toSquared)); 76 77 if (error > angleEpsilon) 78 return false; 79 *axis = from->axis(); 80 *fromAngle = from->angle(); 81 *toAngle = to->angle(); 82 return true; 83 } 84 85 PassRefPtr<TransformOperation> RotateTransformOperation::blend(const TransformOperation* from, double progress, bool blendToIdentity) 86 { 87 if (from && !from->isSameType(*this)) 88 return this; 89 90 if (blendToIdentity) 91 return RotateTransformOperation::create(m_x, m_y, m_z, m_angle - m_angle * progress, m_type); 92 93 const RotateTransformOperation* fromOp = static_cast<const RotateTransformOperation*>(from); 94 95 // Optimize for single axis rotation 96 if (!fromOp || (fromOp->m_x == 0 && fromOp->m_y == 0 && fromOp->m_z == 1) || 97 (fromOp->m_x == 0 && fromOp->m_y == 1 && fromOp->m_z == 0) || 98 (fromOp->m_x == 1 && fromOp->m_y == 0 && fromOp->m_z == 0)) { 99 double fromAngle = fromOp ? fromOp->m_angle : 0; 100 return RotateTransformOperation::create(fromOp ? fromOp->m_x : m_x, 101 fromOp ? fromOp->m_y : m_y, 102 fromOp ? fromOp->m_z : m_z, 103 WebCore::blend(fromAngle, m_angle, progress), m_type); 104 } 105 double fromAngle; 106 double toAngle; 107 FloatPoint3D axis; 108 109 if (shareSameAxis(fromOp, this, &axis, &fromAngle, &toAngle)) 110 return RotateTransformOperation::create(axis.x(), axis.y(), axis.z(), WebCore::blend(fromAngle, toAngle, progress), m_type); 111 112 const RotateTransformOperation* toOp = this; 113 114 // Create the 2 rotation matrices 115 TransformationMatrix fromT; 116 TransformationMatrix toT; 117 fromT.rotate3d((fromOp ? fromOp->m_x : 0), 118 (fromOp ? fromOp->m_y : 0), 119 (fromOp ? fromOp->m_z : 1), 120 (fromOp ? fromOp->m_angle : 0)); 121 122 toT.rotate3d((toOp ? toOp->m_x : 0), 123 (toOp ? toOp->m_y : 0), 124 (toOp ? toOp->m_z : 1), 125 (toOp ? toOp->m_angle : 0)); 126 127 // Blend them 128 toT.blend(fromT, progress); 129 130 // Extract the result as a quaternion 131 TransformationMatrix::DecomposedType decomp; 132 toT.decompose(decomp); 133 134 // Convert that to Axis/Angle form 135 double x = -decomp.quaternionX; 136 double y = -decomp.quaternionY; 137 double z = -decomp.quaternionZ; 138 double length = sqrt(x * x + y * y + z * z); 139 double angle = 0; 140 141 if (length > 0.00001) { 142 x /= length; 143 y /= length; 144 z /= length; 145 angle = rad2deg(acos(decomp.quaternionW) * 2); 146 } else { 147 x = 0; 148 y = 0; 149 z = 1; 150 } 151 return RotateTransformOperation::create(x, y, z, angle, Rotate3D); 152 } 153 154 bool RotateTransformOperation::canBlendWith(const TransformOperation& other) const 155 { 156 return other.isSameType(*this); 157 } 158 159 } // namespace WebCore 160
