[5789] | 1 | /* |
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| 2 | ----------------------------------------------------------------------------- |
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| 3 | This source file is part of OGRE |
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| 4 | (Object-oriented Graphics Rendering Engine) |
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| 5 | For the latest info, see http://www.ogre3d.org/ |
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| 6 | |
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| 7 | Copyright (c) 2000-2006 Torus Knot Software Ltd |
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| 8 | Also see acknowledgements in Readme.html |
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| 9 | |
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| 10 | This program is free software; you can redistribute it and/or modify it under |
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| 11 | the terms of the GNU Lesser General Public License as published by the Free Software |
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| 12 | Foundation; either version 2 of the License, or (at your option) any later |
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| 13 | version. |
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| 14 | |
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| 15 | This program is distributed in the hope that it will be useful, but WITHOUT |
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| 16 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
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| 17 | FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. |
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| 18 | |
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| 19 | You should have received a copy of the GNU Lesser General Public License along with |
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| 20 | this program; if not, write to the Free Software Foundation, Inc., 59 Temple |
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| 21 | Place - Suite 330, Boston, MA 02111-1307, USA, or go to |
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| 22 | http://www.gnu.org/copyleft/lesser.txt. |
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| 23 | |
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| 24 | You may alternatively use this source under the terms of a specific version of |
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| 25 | the OGRE Unrestricted License provided you have obtained such a license from |
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| 26 | Torus Knot Software Ltd. |
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| 27 | ----------------------------------------------------------------------------- |
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| 28 | */ |
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| 29 | // NOTE THAT THIS FILE IS BASED ON MATERIAL FROM: |
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| 30 | |
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| 31 | // Magic Software, Inc. |
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| 32 | // http://www.geometrictools.com |
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| 33 | // Copyright (c) 2000, All Rights Reserved |
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| 34 | // |
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| 35 | // Source code from Magic Software is supplied under the terms of a license |
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| 36 | // agreement and may not be copied or disclosed except in accordance with the |
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| 37 | // terms of that agreement. The various license agreements may be found at |
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| 38 | // the Magic Software web site. This file is subject to the license |
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| 39 | // |
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| 40 | // FREE SOURCE CODE |
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| 41 | // http://www.geometrictools.com/License/WildMagic3License.pdf |
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| 42 | |
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| 43 | #include "OgreQuaternion.h" |
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| 44 | |
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| 45 | #include "OgreMath.h" |
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| 46 | #include "OgreMatrix3.h" |
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| 47 | #include "OgreVector3.h" |
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| 48 | |
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| 49 | namespace Ogre { |
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| 50 | |
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| 51 | const Real Quaternion::ms_fEpsilon = 1e-03; |
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| 52 | const Quaternion Quaternion::ZERO(0.0,0.0,0.0,0.0); |
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| 53 | const Quaternion Quaternion::IDENTITY(1.0,0.0,0.0,0.0); |
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| 54 | |
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| 55 | //----------------------------------------------------------------------- |
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| 56 | void Quaternion::FromRotationMatrix (const Matrix3& kRot) |
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| 57 | { |
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| 58 | // Algorithm in Ken Shoemake's article in 1987 SIGGRAPH course notes |
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| 59 | // article "Quaternion Calculus and Fast Animation". |
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| 60 | |
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| 61 | Real fTrace = kRot[0][0]+kRot[1][1]+kRot[2][2]; |
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| 62 | Real fRoot; |
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| 63 | |
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| 64 | if ( fTrace > 0.0 ) |
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| 65 | { |
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| 66 | // |w| > 1/2, may as well choose w > 1/2 |
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| 67 | fRoot = Math::Sqrt(fTrace + 1.0); // 2w |
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| 68 | w = 0.5*fRoot; |
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| 69 | fRoot = 0.5/fRoot; // 1/(4w) |
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| 70 | x = (kRot[2][1]-kRot[1][2])*fRoot; |
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| 71 | y = (kRot[0][2]-kRot[2][0])*fRoot; |
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| 72 | z = (kRot[1][0]-kRot[0][1])*fRoot; |
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| 73 | } |
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| 74 | else |
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| 75 | { |
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| 76 | // |w| <= 1/2 |
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| 77 | static size_t s_iNext[3] = { 1, 2, 0 }; |
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| 78 | size_t i = 0; |
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| 79 | if ( kRot[1][1] > kRot[0][0] ) |
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| 80 | i = 1; |
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| 81 | if ( kRot[2][2] > kRot[i][i] ) |
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| 82 | i = 2; |
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| 83 | size_t j = s_iNext[i]; |
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| 84 | size_t k = s_iNext[j]; |
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| 85 | |
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| 86 | fRoot = Math::Sqrt(kRot[i][i]-kRot[j][j]-kRot[k][k] + 1.0); |
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| 87 | Real* apkQuat[3] = { &x, &y, &z }; |
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| 88 | *apkQuat[i] = 0.5*fRoot; |
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| 89 | fRoot = 0.5/fRoot; |
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| 90 | w = (kRot[k][j]-kRot[j][k])*fRoot; |
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| 91 | *apkQuat[j] = (kRot[j][i]+kRot[i][j])*fRoot; |
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| 92 | *apkQuat[k] = (kRot[k][i]+kRot[i][k])*fRoot; |
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| 93 | } |
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| 94 | } |
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| 95 | //----------------------------------------------------------------------- |
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| 96 | void Quaternion::ToRotationMatrix (Matrix3& kRot) const |
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| 97 | { |
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| 98 | Real fTx = 2.0*x; |
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| 99 | Real fTy = 2.0*y; |
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| 100 | Real fTz = 2.0*z; |
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| 101 | Real fTwx = fTx*w; |
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| 102 | Real fTwy = fTy*w; |
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| 103 | Real fTwz = fTz*w; |
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| 104 | Real fTxx = fTx*x; |
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| 105 | Real fTxy = fTy*x; |
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| 106 | Real fTxz = fTz*x; |
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| 107 | Real fTyy = fTy*y; |
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| 108 | Real fTyz = fTz*y; |
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| 109 | Real fTzz = fTz*z; |
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| 110 | |
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| 111 | kRot[0][0] = 1.0-(fTyy+fTzz); |
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| 112 | kRot[0][1] = fTxy-fTwz; |
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| 113 | kRot[0][2] = fTxz+fTwy; |
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| 114 | kRot[1][0] = fTxy+fTwz; |
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| 115 | kRot[1][1] = 1.0-(fTxx+fTzz); |
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| 116 | kRot[1][2] = fTyz-fTwx; |
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| 117 | kRot[2][0] = fTxz-fTwy; |
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| 118 | kRot[2][1] = fTyz+fTwx; |
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| 119 | kRot[2][2] = 1.0-(fTxx+fTyy); |
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| 120 | } |
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| 121 | //----------------------------------------------------------------------- |
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| 122 | void Quaternion::FromAngleAxis (const Radian& rfAngle, |
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| 123 | const Vector3& rkAxis) |
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| 124 | { |
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| 125 | // assert: axis[] is unit length |
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| 126 | // |
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| 127 | // The quaternion representing the rotation is |
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| 128 | // q = cos(A/2)+sin(A/2)*(x*i+y*j+z*k) |
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| 129 | |
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| 130 | Radian fHalfAngle ( 0.5*rfAngle ); |
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| 131 | Real fSin = Math::Sin(fHalfAngle); |
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| 132 | w = Math::Cos(fHalfAngle); |
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| 133 | x = fSin*rkAxis.x; |
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| 134 | y = fSin*rkAxis.y; |
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| 135 | z = fSin*rkAxis.z; |
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| 136 | } |
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| 137 | //----------------------------------------------------------------------- |
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| 138 | void Quaternion::ToAngleAxis (Radian& rfAngle, Vector3& rkAxis) const |
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| 139 | { |
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| 140 | // The quaternion representing the rotation is |
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| 141 | // q = cos(A/2)+sin(A/2)*(x*i+y*j+z*k) |
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| 142 | |
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| 143 | Real fSqrLength = x*x+y*y+z*z; |
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| 144 | if ( fSqrLength > 0.0 ) |
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| 145 | { |
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| 146 | rfAngle = 2.0*Math::ACos(w); |
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| 147 | Real fInvLength = Math::InvSqrt(fSqrLength); |
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| 148 | rkAxis.x = x*fInvLength; |
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| 149 | rkAxis.y = y*fInvLength; |
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| 150 | rkAxis.z = z*fInvLength; |
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| 151 | } |
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| 152 | else |
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| 153 | { |
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| 154 | // angle is 0 (mod 2*pi), so any axis will do |
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| 155 | rfAngle = Radian(0.0); |
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| 156 | rkAxis.x = 1.0; |
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| 157 | rkAxis.y = 0.0; |
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| 158 | rkAxis.z = 0.0; |
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| 159 | } |
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| 160 | } |
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| 161 | //----------------------------------------------------------------------- |
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| 162 | void Quaternion::FromAxes (const Vector3* akAxis) |
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| 163 | { |
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| 164 | Matrix3 kRot; |
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| 165 | |
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| 166 | for (size_t iCol = 0; iCol < 3; iCol++) |
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| 167 | { |
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| 168 | kRot[0][iCol] = akAxis[iCol].x; |
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| 169 | kRot[1][iCol] = akAxis[iCol].y; |
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| 170 | kRot[2][iCol] = akAxis[iCol].z; |
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| 171 | } |
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| 172 | |
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| 173 | FromRotationMatrix(kRot); |
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| 174 | } |
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| 175 | //----------------------------------------------------------------------- |
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| 176 | void Quaternion::FromAxes (const Vector3& xaxis, const Vector3& yaxis, const Vector3& zaxis) |
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| 177 | { |
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| 178 | Matrix3 kRot; |
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| 179 | |
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| 180 | kRot[0][0] = xaxis.x; |
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| 181 | kRot[1][0] = xaxis.y; |
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| 182 | kRot[2][0] = xaxis.z; |
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| 183 | |
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| 184 | kRot[0][1] = yaxis.x; |
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| 185 | kRot[1][1] = yaxis.y; |
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| 186 | kRot[2][1] = yaxis.z; |
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| 187 | |
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| 188 | kRot[0][2] = zaxis.x; |
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| 189 | kRot[1][2] = zaxis.y; |
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| 190 | kRot[2][2] = zaxis.z; |
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| 191 | |
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| 192 | FromRotationMatrix(kRot); |
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| 193 | |
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| 194 | } |
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| 195 | //----------------------------------------------------------------------- |
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| 196 | void Quaternion::ToAxes (Vector3* akAxis) const |
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| 197 | { |
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| 198 | Matrix3 kRot; |
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| 199 | |
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| 200 | ToRotationMatrix(kRot); |
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| 201 | |
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| 202 | for (size_t iCol = 0; iCol < 3; iCol++) |
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| 203 | { |
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| 204 | akAxis[iCol].x = kRot[0][iCol]; |
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| 205 | akAxis[iCol].y = kRot[1][iCol]; |
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| 206 | akAxis[iCol].z = kRot[2][iCol]; |
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| 207 | } |
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| 208 | } |
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| 209 | //----------------------------------------------------------------------- |
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| 210 | Vector3 Quaternion::xAxis(void) const |
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| 211 | { |
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| 212 | //Real fTx = 2.0*x; |
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| 213 | Real fTy = 2.0*y; |
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| 214 | Real fTz = 2.0*z; |
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| 215 | Real fTwy = fTy*w; |
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| 216 | Real fTwz = fTz*w; |
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| 217 | Real fTxy = fTy*x; |
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| 218 | Real fTxz = fTz*x; |
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| 219 | Real fTyy = fTy*y; |
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| 220 | Real fTzz = fTz*z; |
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| 221 | |
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| 222 | return Vector3(1.0-(fTyy+fTzz), fTxy+fTwz, fTxz-fTwy); |
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| 223 | } |
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| 224 | //----------------------------------------------------------------------- |
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| 225 | Vector3 Quaternion::yAxis(void) const |
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| 226 | { |
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| 227 | Real fTx = 2.0*x; |
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| 228 | Real fTy = 2.0*y; |
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| 229 | Real fTz = 2.0*z; |
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| 230 | Real fTwx = fTx*w; |
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| 231 | Real fTwz = fTz*w; |
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| 232 | Real fTxx = fTx*x; |
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| 233 | Real fTxy = fTy*x; |
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| 234 | Real fTyz = fTz*y; |
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| 235 | Real fTzz = fTz*z; |
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| 236 | |
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| 237 | return Vector3(fTxy-fTwz, 1.0-(fTxx+fTzz), fTyz+fTwx); |
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| 238 | } |
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| 239 | //----------------------------------------------------------------------- |
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| 240 | Vector3 Quaternion::zAxis(void) const |
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| 241 | { |
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| 242 | Real fTx = 2.0*x; |
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| 243 | Real fTy = 2.0*y; |
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| 244 | Real fTz = 2.0*z; |
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| 245 | Real fTwx = fTx*w; |
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| 246 | Real fTwy = fTy*w; |
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| 247 | Real fTxx = fTx*x; |
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| 248 | Real fTxz = fTz*x; |
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| 249 | Real fTyy = fTy*y; |
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| 250 | Real fTyz = fTz*y; |
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| 251 | |
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| 252 | return Vector3(fTxz+fTwy, fTyz-fTwx, 1.0-(fTxx+fTyy)); |
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| 253 | } |
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| 254 | //----------------------------------------------------------------------- |
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| 255 | void Quaternion::ToAxes (Vector3& xaxis, Vector3& yaxis, Vector3& zaxis) const |
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| 256 | { |
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| 257 | Matrix3 kRot; |
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| 258 | |
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| 259 | ToRotationMatrix(kRot); |
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| 260 | |
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| 261 | xaxis.x = kRot[0][0]; |
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| 262 | xaxis.y = kRot[1][0]; |
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| 263 | xaxis.z = kRot[2][0]; |
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| 264 | |
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| 265 | yaxis.x = kRot[0][1]; |
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| 266 | yaxis.y = kRot[1][1]; |
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| 267 | yaxis.z = kRot[2][1]; |
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| 268 | |
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| 269 | zaxis.x = kRot[0][2]; |
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| 270 | zaxis.y = kRot[1][2]; |
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| 271 | zaxis.z = kRot[2][2]; |
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| 272 | } |
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| 273 | |
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| 274 | //----------------------------------------------------------------------- |
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| 275 | Quaternion Quaternion::operator+ (const Quaternion& rkQ) const |
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| 276 | { |
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| 277 | return Quaternion(w+rkQ.w,x+rkQ.x,y+rkQ.y,z+rkQ.z); |
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| 278 | } |
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| 279 | //----------------------------------------------------------------------- |
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| 280 | Quaternion Quaternion::operator- (const Quaternion& rkQ) const |
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| 281 | { |
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| 282 | return Quaternion(w-rkQ.w,x-rkQ.x,y-rkQ.y,z-rkQ.z); |
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| 283 | } |
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| 284 | //----------------------------------------------------------------------- |
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| 285 | Quaternion Quaternion::operator* (const Quaternion& rkQ) const |
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| 286 | { |
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| 287 | // NOTE: Multiplication is not generally commutative, so in most |
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| 288 | // cases p*q != q*p. |
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| 289 | |
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| 290 | return Quaternion |
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| 291 | ( |
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| 292 | w * rkQ.w - x * rkQ.x - y * rkQ.y - z * rkQ.z, |
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| 293 | w * rkQ.x + x * rkQ.w + y * rkQ.z - z * rkQ.y, |
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| 294 | w * rkQ.y + y * rkQ.w + z * rkQ.x - x * rkQ.z, |
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| 295 | w * rkQ.z + z * rkQ.w + x * rkQ.y - y * rkQ.x |
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| 296 | ); |
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| 297 | } |
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| 298 | //----------------------------------------------------------------------- |
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| 299 | Quaternion Quaternion::operator* (Real fScalar) const |
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| 300 | { |
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| 301 | return Quaternion(fScalar*w,fScalar*x,fScalar*y,fScalar*z); |
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| 302 | } |
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| 303 | //----------------------------------------------------------------------- |
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| 304 | Quaternion operator* (Real fScalar, const Quaternion& rkQ) |
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| 305 | { |
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| 306 | return Quaternion(fScalar*rkQ.w,fScalar*rkQ.x,fScalar*rkQ.y, |
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| 307 | fScalar*rkQ.z); |
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| 308 | } |
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| 309 | //----------------------------------------------------------------------- |
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| 310 | Quaternion Quaternion::operator- () const |
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| 311 | { |
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| 312 | return Quaternion(-w,-x,-y,-z); |
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| 313 | } |
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| 314 | //----------------------------------------------------------------------- |
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| 315 | Real Quaternion::Dot (const Quaternion& rkQ) const |
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| 316 | { |
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| 317 | return w*rkQ.w+x*rkQ.x+y*rkQ.y+z*rkQ.z; |
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| 318 | } |
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| 319 | //----------------------------------------------------------------------- |
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| 320 | Real Quaternion::Norm () const |
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| 321 | { |
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| 322 | return w*w+x*x+y*y+z*z; |
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| 323 | } |
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| 324 | //----------------------------------------------------------------------- |
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| 325 | Quaternion Quaternion::Inverse () const |
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| 326 | { |
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| 327 | Real fNorm = w*w+x*x+y*y+z*z; |
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| 328 | if ( fNorm > 0.0 ) |
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| 329 | { |
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| 330 | Real fInvNorm = 1.0/fNorm; |
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| 331 | return Quaternion(w*fInvNorm,-x*fInvNorm,-y*fInvNorm,-z*fInvNorm); |
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| 332 | } |
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| 333 | else |
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| 334 | { |
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| 335 | // return an invalid result to flag the error |
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| 336 | return ZERO; |
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| 337 | } |
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| 338 | } |
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| 339 | //----------------------------------------------------------------------- |
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| 340 | Quaternion Quaternion::UnitInverse () const |
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| 341 | { |
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| 342 | // assert: 'this' is unit length |
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| 343 | return Quaternion(w,-x,-y,-z); |
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| 344 | } |
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| 345 | //----------------------------------------------------------------------- |
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| 346 | Quaternion Quaternion::Exp () const |
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| 347 | { |
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| 348 | // If q = A*(x*i+y*j+z*k) where (x,y,z) is unit length, then |
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| 349 | // exp(q) = cos(A)+sin(A)*(x*i+y*j+z*k). If sin(A) is near zero, |
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| 350 | // use exp(q) = cos(A)+A*(x*i+y*j+z*k) since A/sin(A) has limit 1. |
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| 351 | |
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| 352 | Radian fAngle ( Math::Sqrt(x*x+y*y+z*z) ); |
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| 353 | Real fSin = Math::Sin(fAngle); |
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| 354 | |
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| 355 | Quaternion kResult; |
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| 356 | kResult.w = Math::Cos(fAngle); |
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| 357 | |
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| 358 | if ( Math::Abs(fSin) >= ms_fEpsilon ) |
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| 359 | { |
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| 360 | Real fCoeff = fSin/(fAngle.valueRadians()); |
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| 361 | kResult.x = fCoeff*x; |
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| 362 | kResult.y = fCoeff*y; |
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| 363 | kResult.z = fCoeff*z; |
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| 364 | } |
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| 365 | else |
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| 366 | { |
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| 367 | kResult.x = x; |
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| 368 | kResult.y = y; |
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| 369 | kResult.z = z; |
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| 370 | } |
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| 371 | |
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| 372 | return kResult; |
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| 373 | } |
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| 374 | //----------------------------------------------------------------------- |
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| 375 | Quaternion Quaternion::Log () const |
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| 376 | { |
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| 377 | // If q = cos(A)+sin(A)*(x*i+y*j+z*k) where (x,y,z) is unit length, then |
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| 378 | // log(q) = A*(x*i+y*j+z*k). If sin(A) is near zero, use log(q) = |
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| 379 | // sin(A)*(x*i+y*j+z*k) since sin(A)/A has limit 1. |
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| 380 | |
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| 381 | Quaternion kResult; |
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| 382 | kResult.w = 0.0; |
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| 383 | |
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| 384 | if ( Math::Abs(w) < 1.0 ) |
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| 385 | { |
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| 386 | Radian fAngle ( Math::ACos(w) ); |
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| 387 | Real fSin = Math::Sin(fAngle); |
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| 388 | if ( Math::Abs(fSin) >= ms_fEpsilon ) |
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| 389 | { |
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| 390 | Real fCoeff = fAngle.valueRadians()/fSin; |
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| 391 | kResult.x = fCoeff*x; |
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| 392 | kResult.y = fCoeff*y; |
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| 393 | kResult.z = fCoeff*z; |
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| 394 | return kResult; |
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| 395 | } |
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| 396 | } |
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| 397 | |
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| 398 | kResult.x = x; |
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| 399 | kResult.y = y; |
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| 400 | kResult.z = z; |
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| 401 | |
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| 402 | return kResult; |
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| 403 | } |
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| 404 | //----------------------------------------------------------------------- |
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| 405 | Vector3 Quaternion::operator* (const Vector3& v) const |
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| 406 | { |
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| 407 | // nVidia SDK implementation |
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| 408 | Vector3 uv, uuv; |
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| 409 | Vector3 qvec(x, y, z); |
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| 410 | uv = qvec.crossProduct(v); |
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| 411 | uuv = qvec.crossProduct(uv); |
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| 412 | uv *= (2.0f * w); |
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| 413 | uuv *= 2.0f; |
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| 414 | |
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| 415 | return v + uv + uuv; |
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| 416 | |
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| 417 | } |
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| 418 | //----------------------------------------------------------------------- |
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| 419 | bool Quaternion::equals(const Quaternion& rhs, const Radian& tolerance) const |
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| 420 | { |
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| 421 | Real fCos = Dot(rhs); |
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| 422 | Radian angle = Math::ACos(fCos); |
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| 423 | |
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| 424 | return (Math::Abs(angle.valueRadians()) <= tolerance.valueRadians()) |
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| 425 | || Math::RealEqual(angle.valueRadians(), Math::PI, tolerance.valueRadians()); |
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| 426 | |
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| 427 | |
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| 428 | } |
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| 429 | //----------------------------------------------------------------------- |
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| 430 | Quaternion Quaternion::Slerp (Real fT, const Quaternion& rkP, |
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| 431 | const Quaternion& rkQ, bool shortestPath) |
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| 432 | { |
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| 433 | Real fCos = rkP.Dot(rkQ); |
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| 434 | Quaternion rkT; |
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| 435 | |
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| 436 | // Do we need to invert rotation? |
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| 437 | if (fCos < 0.0f && shortestPath) |
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| 438 | { |
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| 439 | fCos = -fCos; |
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| 440 | rkT = -rkQ; |
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| 441 | } |
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| 442 | else |
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| 443 | { |
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| 444 | rkT = rkQ; |
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| 445 | } |
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| 446 | |
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| 447 | if (Math::Abs(fCos) < 1 - ms_fEpsilon) |
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| 448 | { |
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| 449 | // Standard case (slerp) |
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| 450 | Real fSin = Math::Sqrt(1 - Math::Sqr(fCos)); |
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| 451 | Radian fAngle = Math::ATan2(fSin, fCos); |
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| 452 | Real fInvSin = 1.0f / fSin; |
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| 453 | Real fCoeff0 = Math::Sin((1.0f - fT) * fAngle) * fInvSin; |
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| 454 | Real fCoeff1 = Math::Sin(fT * fAngle) * fInvSin; |
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| 455 | return fCoeff0 * rkP + fCoeff1 * rkT; |
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| 456 | } |
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| 457 | else |
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| 458 | { |
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| 459 | // There are two situations: |
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| 460 | // 1. "rkP" and "rkQ" are very close (fCos ~= +1), so we can do a linear |
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| 461 | // interpolation safely. |
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| 462 | // 2. "rkP" and "rkQ" are almost inverse of each other (fCos ~= -1), there |
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| 463 | // are an infinite number of possibilities interpolation. but we haven't |
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| 464 | // have method to fix this case, so just use linear interpolation here. |
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| 465 | Quaternion t = (1.0f - fT) * rkP + fT * rkT; |
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| 466 | // taking the complement requires renormalisation |
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| 467 | t.normalise(); |
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| 468 | return t; |
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| 469 | } |
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| 470 | } |
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| 471 | //----------------------------------------------------------------------- |
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| 472 | Quaternion Quaternion::SlerpExtraSpins (Real fT, |
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| 473 | const Quaternion& rkP, const Quaternion& rkQ, int iExtraSpins) |
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| 474 | { |
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| 475 | Real fCos = rkP.Dot(rkQ); |
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| 476 | Radian fAngle ( Math::ACos(fCos) ); |
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| 477 | |
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| 478 | if ( Math::Abs(fAngle.valueRadians()) < ms_fEpsilon ) |
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| 479 | return rkP; |
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| 480 | |
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| 481 | Real fSin = Math::Sin(fAngle); |
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| 482 | Radian fPhase ( Math::PI*iExtraSpins*fT ); |
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| 483 | Real fInvSin = 1.0/fSin; |
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| 484 | Real fCoeff0 = Math::Sin((1.0-fT)*fAngle - fPhase)*fInvSin; |
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| 485 | Real fCoeff1 = Math::Sin(fT*fAngle + fPhase)*fInvSin; |
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| 486 | return fCoeff0*rkP + fCoeff1*rkQ; |
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| 487 | } |
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| 488 | //----------------------------------------------------------------------- |
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| 489 | void Quaternion::Intermediate (const Quaternion& rkQ0, |
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| 490 | const Quaternion& rkQ1, const Quaternion& rkQ2, |
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| 491 | Quaternion& rkA, Quaternion& rkB) |
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| 492 | { |
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| 493 | // assert: q0, q1, q2 are unit quaternions |
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| 494 | |
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| 495 | Quaternion kQ0inv = rkQ0.UnitInverse(); |
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| 496 | Quaternion kQ1inv = rkQ1.UnitInverse(); |
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| 497 | Quaternion rkP0 = kQ0inv*rkQ1; |
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| 498 | Quaternion rkP1 = kQ1inv*rkQ2; |
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| 499 | Quaternion kArg = 0.25*(rkP0.Log()-rkP1.Log()); |
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| 500 | Quaternion kMinusArg = -kArg; |
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| 501 | |
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| 502 | rkA = rkQ1*kArg.Exp(); |
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| 503 | rkB = rkQ1*kMinusArg.Exp(); |
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| 504 | } |
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| 505 | //----------------------------------------------------------------------- |
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| 506 | Quaternion Quaternion::Squad (Real fT, |
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| 507 | const Quaternion& rkP, const Quaternion& rkA, |
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| 508 | const Quaternion& rkB, const Quaternion& rkQ, bool shortestPath) |
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| 509 | { |
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| 510 | Real fSlerpT = 2.0*fT*(1.0-fT); |
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| 511 | Quaternion kSlerpP = Slerp(fT, rkP, rkQ, shortestPath); |
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| 512 | Quaternion kSlerpQ = Slerp(fT, rkA, rkB); |
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| 513 | return Slerp(fSlerpT, kSlerpP ,kSlerpQ); |
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| 514 | } |
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| 515 | //----------------------------------------------------------------------- |
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| 516 | Real Quaternion::normalise(void) |
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| 517 | { |
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| 518 | Real len = Norm(); |
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| 519 | Real factor = 1.0f / Math::Sqrt(len); |
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| 520 | *this = *this * factor; |
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| 521 | return len; |
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| 522 | } |
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| 523 | //----------------------------------------------------------------------- |
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| 524 | Radian Quaternion::getRoll(bool reprojectAxis) const |
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| 525 | { |
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| 526 | if (reprojectAxis) |
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| 527 | { |
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| 528 | // roll = atan2(localx.y, localx.x) |
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| 529 | // pick parts of xAxis() implementation that we need |
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| 530 | Real fTx = 2.0*x; |
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| 531 | Real fTy = 2.0*y; |
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| 532 | Real fTz = 2.0*z; |
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| 533 | Real fTwz = fTz*w; |
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| 534 | Real fTxy = fTy*x; |
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| 535 | Real fTyy = fTy*y; |
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| 536 | Real fTzz = fTz*z; |
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| 537 | |
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| 538 | // Vector3(1.0-(fTyy+fTzz), fTxy+fTwz, fTxz-fTwy); |
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| 539 | |
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| 540 | return Radian(Math::ATan2(fTxy+fTwz, 1.0-(fTyy+fTzz))); |
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| 541 | |
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| 542 | } |
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| 543 | else |
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| 544 | { |
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| 545 | return Radian(Math::ATan2(2*(x*y + w*z), w*w + x*x - y*y - z*z)); |
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| 546 | } |
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| 547 | } |
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| 548 | //----------------------------------------------------------------------- |
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| 549 | Radian Quaternion::getPitch(bool reprojectAxis) const |
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| 550 | { |
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| 551 | if (reprojectAxis) |
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| 552 | { |
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| 553 | // pitch = atan2(localy.z, localy.y) |
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| 554 | // pick parts of yAxis() implementation that we need |
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| 555 | Real fTx = 2.0*x; |
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| 556 | Real fTy = 2.0*y; |
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| 557 | Real fTz = 2.0*z; |
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| 558 | Real fTwx = fTx*w; |
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| 559 | Real fTxx = fTx*x; |
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| 560 | Real fTyz = fTz*y; |
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| 561 | Real fTzz = fTz*z; |
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| 562 | |
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| 563 | // Vector3(fTxy-fTwz, 1.0-(fTxx+fTzz), fTyz+fTwx); |
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| 564 | return Radian(Math::ATan2(fTyz+fTwx, 1.0-(fTxx+fTzz))); |
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| 565 | } |
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| 566 | else |
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| 567 | { |
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| 568 | // internal version |
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| 569 | return Radian(Math::ATan2(2*(y*z + w*x), w*w - x*x - y*y + z*z)); |
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| 570 | } |
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| 571 | } |
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| 572 | //----------------------------------------------------------------------- |
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| 573 | Radian Quaternion::getYaw(bool reprojectAxis) const |
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| 574 | { |
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| 575 | if (reprojectAxis) |
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| 576 | { |
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| 577 | // yaw = atan2(localz.x, localz.z) |
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| 578 | // pick parts of zAxis() implementation that we need |
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| 579 | Real fTx = 2.0*x; |
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| 580 | Real fTy = 2.0*y; |
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| 581 | Real fTz = 2.0*z; |
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| 582 | Real fTwy = fTy*w; |
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| 583 | Real fTxx = fTx*x; |
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| 584 | Real fTxz = fTz*x; |
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| 585 | Real fTyy = fTy*y; |
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| 586 | |
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| 587 | // Vector3(fTxz+fTwy, fTyz-fTwx, 1.0-(fTxx+fTyy)); |
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| 588 | |
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| 589 | return Radian(Math::ATan2(fTxz+fTwy, 1.0-(fTxx+fTyy))); |
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| 590 | |
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| 591 | } |
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| 592 | else |
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| 593 | { |
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| 594 | // internal version |
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| 595 | return Radian(Math::ASin(-2*(x*z - w*y))); |
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| 596 | } |
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| 597 | } |
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| 598 | //----------------------------------------------------------------------- |
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| 599 | Quaternion Quaternion::nlerp(Real fT, const Quaternion& rkP, |
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| 600 | const Quaternion& rkQ, bool shortestPath) |
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| 601 | { |
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| 602 | Quaternion result; |
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| 603 | Real fCos = rkP.Dot(rkQ); |
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| 604 | if (fCos < 0.0f && shortestPath) |
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| 605 | { |
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| 606 | result = rkP + fT * ((-rkQ) - rkP); |
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| 607 | } |
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| 608 | else |
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| 609 | { |
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| 610 | result = rkP + fT * (rkQ - rkP); |
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| 611 | } |
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| 612 | result.normalise(); |
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| 613 | return result; |
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| 614 | } |
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| 615 | } |
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