llquaternion.cpp
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- /**
- * @file llquaternion.cpp
- * @brief LLQuaternion class implementation.
- *
- * $LicenseInfo:firstyear=2000&license=viewergpl$
- *
- * Copyright (c) 2000-2010, Linden Research, Inc.
- *
- * Second Life Viewer Source Code
- * The source code in this file ("Source Code") is provided by Linden Lab
- * to you under the terms of the GNU General Public License, version 2.0
- * ("GPL"), unless you have obtained a separate licensing agreement
- * ("Other License"), formally executed by you and Linden Lab. Terms of
- * the GPL can be found in doc/GPL-license.txt in this distribution, or
- * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
- *
- * There are special exceptions to the terms and conditions of the GPL as
- * it is applied to this Source Code. View the full text of the exception
- * in the file doc/FLOSS-exception.txt in this software distribution, or
- * online at
- * http://secondlifegrid.net/programs/open_source/licensing/flossexception
- *
- * By copying, modifying or distributing this software, you acknowledge
- * that you have read and understood your obligations described above,
- * and agree to abide by those obligations.
- *
- * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
- * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
- * COMPLETENESS OR PERFORMANCE.
- * $/LicenseInfo$
- */
- #include "linden_common.h"
- #include "llquaternion.h"
- #include "llmath.h" // for F_PI
- //#include "vmath.h"
- #include "v3math.h"
- #include "v3dmath.h"
- #include "v4math.h"
- #include "m4math.h"
- #include "m3math.h"
- #include "llquantize.h"
- // WARNING: Don't use this for global const definitions! using this
- // at the top of a *.cpp file might not give you what you think.
- const LLQuaternion LLQuaternion::DEFAULT;
-
- // Constructors
- LLQuaternion::LLQuaternion(const LLMatrix4 &mat)
- {
- *this = mat.quaternion();
- normalize();
- }
- LLQuaternion::LLQuaternion(const LLMatrix3 &mat)
- {
- *this = mat.quaternion();
- normalize();
- }
- LLQuaternion::LLQuaternion(F32 angle, const LLVector4 &vec)
- {
- LLVector3 v(vec.mV[VX], vec.mV[VY], vec.mV[VZ]);
- v.normalize();
- F32 c, s;
- c = cosf(angle*0.5f);
- s = sinf(angle*0.5f);
- mQ[VX] = v.mV[VX] * s;
- mQ[VY] = v.mV[VY] * s;
- mQ[VZ] = v.mV[VZ] * s;
- mQ[VW] = c;
- normalize();
- }
- LLQuaternion::LLQuaternion(F32 angle, const LLVector3 &vec)
- {
- LLVector3 v(vec);
- v.normalize();
- F32 c, s;
- c = cosf(angle*0.5f);
- s = sinf(angle*0.5f);
- mQ[VX] = v.mV[VX] * s;
- mQ[VY] = v.mV[VY] * s;
- mQ[VZ] = v.mV[VZ] * s;
- mQ[VW] = c;
- normalize();
- }
- LLQuaternion::LLQuaternion(const LLVector3 &x_axis,
- const LLVector3 &y_axis,
- const LLVector3 &z_axis)
- {
- LLMatrix3 mat;
- mat.setRows(x_axis, y_axis, z_axis);
- *this = mat.quaternion();
- normalize();
- }
- // Quatizations
- void LLQuaternion::quantize16(F32 lower, F32 upper)
- {
- F32 x = mQ[VX];
- F32 y = mQ[VY];
- F32 z = mQ[VZ];
- F32 s = mQ[VS];
- x = U16_to_F32(F32_to_U16_ROUND(x, lower, upper), lower, upper);
- y = U16_to_F32(F32_to_U16_ROUND(y, lower, upper), lower, upper);
- z = U16_to_F32(F32_to_U16_ROUND(z, lower, upper), lower, upper);
- s = U16_to_F32(F32_to_U16_ROUND(s, lower, upper), lower, upper);
- mQ[VX] = x;
- mQ[VY] = y;
- mQ[VZ] = z;
- mQ[VS] = s;
- normalize();
- }
- void LLQuaternion::quantize8(F32 lower, F32 upper)
- {
- mQ[VX] = U8_to_F32(F32_to_U8_ROUND(mQ[VX], lower, upper), lower, upper);
- mQ[VY] = U8_to_F32(F32_to_U8_ROUND(mQ[VY], lower, upper), lower, upper);
- mQ[VZ] = U8_to_F32(F32_to_U8_ROUND(mQ[VZ], lower, upper), lower, upper);
- mQ[VS] = U8_to_F32(F32_to_U8_ROUND(mQ[VS], lower, upper), lower, upper);
- normalize();
- }
- // LLVector3 Magnitude and Normalization Functions
- // Set LLQuaternion routines
- const LLQuaternion& LLQuaternion::setAngleAxis(F32 angle, F32 x, F32 y, F32 z)
- {
- LLVector3 vec(x, y, z);
- vec.normalize();
- angle *= 0.5f;
- F32 c, s;
- c = cosf(angle);
- s = sinf(angle);
- mQ[VX] = vec.mV[VX]*s;
- mQ[VY] = vec.mV[VY]*s;
- mQ[VZ] = vec.mV[VZ]*s;
- mQ[VW] = c;
- normalize();
- return (*this);
- }
- const LLQuaternion& LLQuaternion::setAngleAxis(F32 angle, const LLVector3 &vec)
- {
- LLVector3 v(vec);
- v.normalize();
- angle *= 0.5f;
- F32 c, s;
- c = cosf(angle);
- s = sinf(angle);
- mQ[VX] = v.mV[VX]*s;
- mQ[VY] = v.mV[VY]*s;
- mQ[VZ] = v.mV[VZ]*s;
- mQ[VW] = c;
- normalize();
- return (*this);
- }
- const LLQuaternion& LLQuaternion::setAngleAxis(F32 angle, const LLVector4 &vec)
- {
- LLVector3 v(vec.mV[VX], vec.mV[VY], vec.mV[VZ]);
- v.normalize();
- F32 c, s;
- c = cosf(angle*0.5f);
- s = sinf(angle*0.5f);
- mQ[VX] = v.mV[VX]*s;
- mQ[VY] = v.mV[VY]*s;
- mQ[VZ] = v.mV[VZ]*s;
- mQ[VW] = c;
- normalize();
- return (*this);
- }
- const LLQuaternion& LLQuaternion::setEulerAngles(F32 roll, F32 pitch, F32 yaw)
- {
- LLMatrix3 rot_mat(roll, pitch, yaw);
- rot_mat.orthogonalize();
- *this = rot_mat.quaternion();
-
- normalize();
- return (*this);
- }
- // deprecated
- const LLQuaternion& LLQuaternion::set(const LLMatrix3 &mat)
- {
- *this = mat.quaternion();
- normalize();
- return (*this);
- }
- // deprecated
- const LLQuaternion& LLQuaternion::set(const LLMatrix4 &mat)
- {
- *this = mat.quaternion();
- normalize();
- return (*this);
- }
- // deprecated
- const LLQuaternion& LLQuaternion::setQuat(F32 angle, F32 x, F32 y, F32 z)
- {
- LLVector3 vec(x, y, z);
- vec.normalize();
- angle *= 0.5f;
- F32 c, s;
- c = cosf(angle);
- s = sinf(angle);
- mQ[VX] = vec.mV[VX]*s;
- mQ[VY] = vec.mV[VY]*s;
- mQ[VZ] = vec.mV[VZ]*s;
- mQ[VW] = c;
- normalize();
- return (*this);
- }
- // deprecated
- const LLQuaternion& LLQuaternion::setQuat(F32 angle, const LLVector3 &vec)
- {
- LLVector3 v(vec);
- v.normalize();
- angle *= 0.5f;
- F32 c, s;
- c = cosf(angle);
- s = sinf(angle);
- mQ[VX] = v.mV[VX]*s;
- mQ[VY] = v.mV[VY]*s;
- mQ[VZ] = v.mV[VZ]*s;
- mQ[VW] = c;
- normalize();
- return (*this);
- }
- const LLQuaternion& LLQuaternion::setQuat(F32 angle, const LLVector4 &vec)
- {
- LLVector3 v(vec.mV[VX], vec.mV[VY], vec.mV[VZ]);
- v.normalize();
- F32 c, s;
- c = cosf(angle*0.5f);
- s = sinf(angle*0.5f);
- mQ[VX] = v.mV[VX]*s;
- mQ[VY] = v.mV[VY]*s;
- mQ[VZ] = v.mV[VZ]*s;
- mQ[VW] = c;
- normalize();
- return (*this);
- }
- const LLQuaternion& LLQuaternion::setQuat(F32 roll, F32 pitch, F32 yaw)
- {
- LLMatrix3 rot_mat(roll, pitch, yaw);
- rot_mat.orthogonalize();
- *this = rot_mat.quaternion();
-
- normalize();
- return (*this);
- }
- const LLQuaternion& LLQuaternion::setQuat(const LLMatrix3 &mat)
- {
- *this = mat.quaternion();
- normalize();
- return (*this);
- }
- const LLQuaternion& LLQuaternion::setQuat(const LLMatrix4 &mat)
- {
- *this = mat.quaternion();
- normalize();
- return (*this);
- //#if 1
- // // NOTE: LLQuaternion's are actually inverted with respect to
- // // the matrices, so this code also assumes inverted quaternions
- // // (-x, -y, -z, w). The result is that roll,pitch,yaw are applied
- // // in reverse order (yaw,pitch,roll).
- // F64 cosX = cos(roll);
- // F64 cosY = cos(pitch);
- // F64 cosZ = cos(yaw);
- //
- // F64 sinX = sin(roll);
- // F64 sinY = sin(pitch);
- // F64 sinZ = sin(yaw);
- //
- // mQ[VW] = (F32)sqrt(cosY*cosZ - sinX*sinY*sinZ + cosX*cosZ + cosX*cosY + 1.0)*.5;
- // if (fabs(mQ[VW]) < F_APPROXIMATELY_ZERO)
- // {
- // // null rotation, any axis will do
- // mQ[VX] = 0.0f;
- // mQ[VY] = 1.0f;
- // mQ[VZ] = 0.0f;
- // }
- // else
- // {
- // F32 inv_s = 1.0f / (4.0f * mQ[VW]);
- // mQ[VX] = (F32)-(-sinX*cosY - cosX*sinY*sinZ - sinX*cosZ) * inv_s;
- // mQ[VY] = (F32)-(-cosX*sinY*cosZ + sinX*sinZ - sinY) * inv_s;
- // mQ[VZ] = (F32)-(-cosY*sinZ - sinX*sinY*cosZ - cosX*sinZ) * inv_s;
- // }
- //
- //#else // This only works on a certain subset of roll/pitch/yaw
- //
- // F64 cosX = cosf(roll/2.0);
- // F64 cosY = cosf(pitch/2.0);
- // F64 cosZ = cosf(yaw/2.0);
- //
- // F64 sinX = sinf(roll/2.0);
- // F64 sinY = sinf(pitch/2.0);
- // F64 sinZ = sinf(yaw/2.0);
- //
- // mQ[VW] = (F32)(cosX*cosY*cosZ + sinX*sinY*sinZ);
- // mQ[VX] = (F32)(sinX*cosY*cosZ - cosX*sinY*sinZ);
- // mQ[VY] = (F32)(cosX*sinY*cosZ + sinX*cosY*sinZ);
- // mQ[VZ] = (F32)(cosX*cosY*sinZ - sinX*sinY*cosZ);
- //#endif
- //
- // normalize();
- // return (*this);
- }
- // SJB: This code is correct for a logicly stored (non-transposed) matrix;
- // Our matrices are stored transposed, OpenGL style, so this generates the
- // INVERSE matrix, or the CORRECT matrix form an INVERSE quaternion.
- // Because we use similar logic in LLMatrix3::quaternion(),
- // we are internally consistant so everything works OK :)
- LLMatrix3 LLQuaternion::getMatrix3(void) const
- {
- LLMatrix3 mat;
- F32 xx, xy, xz, xw, yy, yz, yw, zz, zw;
- xx = mQ[VX] * mQ[VX];
- xy = mQ[VX] * mQ[VY];
- xz = mQ[VX] * mQ[VZ];
- xw = mQ[VX] * mQ[VW];
- yy = mQ[VY] * mQ[VY];
- yz = mQ[VY] * mQ[VZ];
- yw = mQ[VY] * mQ[VW];
- zz = mQ[VZ] * mQ[VZ];
- zw = mQ[VZ] * mQ[VW];
- mat.mMatrix[0][0] = 1.f - 2.f * ( yy + zz );
- mat.mMatrix[0][1] = 2.f * ( xy + zw );
- mat.mMatrix[0][2] = 2.f * ( xz - yw );
- mat.mMatrix[1][0] = 2.f * ( xy - zw );
- mat.mMatrix[1][1] = 1.f - 2.f * ( xx + zz );
- mat.mMatrix[1][2] = 2.f * ( yz + xw );
- mat.mMatrix[2][0] = 2.f * ( xz + yw );
- mat.mMatrix[2][1] = 2.f * ( yz - xw );
- mat.mMatrix[2][2] = 1.f - 2.f * ( xx + yy );
- return mat;
- }
- LLMatrix4 LLQuaternion::getMatrix4(void) const
- {
- LLMatrix4 mat;
- F32 xx, xy, xz, xw, yy, yz, yw, zz, zw;
- xx = mQ[VX] * mQ[VX];
- xy = mQ[VX] * mQ[VY];
- xz = mQ[VX] * mQ[VZ];
- xw = mQ[VX] * mQ[VW];
- yy = mQ[VY] * mQ[VY];
- yz = mQ[VY] * mQ[VZ];
- yw = mQ[VY] * mQ[VW];
- zz = mQ[VZ] * mQ[VZ];
- zw = mQ[VZ] * mQ[VW];
- mat.mMatrix[0][0] = 1.f - 2.f * ( yy + zz );
- mat.mMatrix[0][1] = 2.f * ( xy + zw );
- mat.mMatrix[0][2] = 2.f * ( xz - yw );
- mat.mMatrix[1][0] = 2.f * ( xy - zw );
- mat.mMatrix[1][1] = 1.f - 2.f * ( xx + zz );
- mat.mMatrix[1][2] = 2.f * ( yz + xw );
- mat.mMatrix[2][0] = 2.f * ( xz + yw );
- mat.mMatrix[2][1] = 2.f * ( yz - xw );
- mat.mMatrix[2][2] = 1.f - 2.f * ( xx + yy );
- // TODO -- should we set the translation portion to zero?
- return mat;
- }
- // Other useful methods
- // calculate the shortest rotation from a to b
- void LLQuaternion::shortestArc(const LLVector3 &a, const LLVector3 &b)
- {
- // Make a local copy of both vectors.
- LLVector3 vec_a = a;
- LLVector3 vec_b = b;
- // Make sure neither vector is zero length. Also normalize
- // the vectors while we are at it.
- F32 vec_a_mag = vec_a.normalize();
- F32 vec_b_mag = vec_b.normalize();
- if (vec_a_mag < F_APPROXIMATELY_ZERO ||
- vec_b_mag < F_APPROXIMATELY_ZERO)
- {
- // Can't calculate a rotation from this.
- // Just return ZERO_ROTATION instead.
- loadIdentity();
- return;
- }
- // Create an axis to rotate around, and the cos of the angle to rotate.
- LLVector3 axis = vec_a % vec_b;
- F32 cos_theta = vec_a * vec_b;
- // Check the angle between the vectors to see if they are parallel or anti-parallel.
- if (cos_theta > 1.0 - F_APPROXIMATELY_ZERO)
- {
- // a and b are parallel. No rotation is necessary.
- loadIdentity();
- }
- else if (cos_theta < -1.0 + F_APPROXIMATELY_ZERO)
- {
- // a and b are anti-parallel.
- // Rotate 180 degrees around some orthogonal axis.
- // Find the projection of the x-axis onto a, and try
- // using the vector between the projection and the x-axis
- // as the orthogonal axis.
- LLVector3 proj = vec_a.mV[VX] / (vec_a * vec_a) * vec_a;
- LLVector3 ortho_axis(1.f, 0.f, 0.f);
- ortho_axis -= proj;
-
- // Turn this into an orthonormal axis.
- F32 ortho_length = ortho_axis.normalize();
- // If the axis' length is 0, then our guess at an orthogonal axis
- // was wrong (a is parallel to the x-axis).
- if (ortho_length < F_APPROXIMATELY_ZERO)
- {
- // Use the z-axis instead.
- ortho_axis.setVec(0.f, 0.f, 1.f);
- }
- // Construct a quaternion from this orthonormal axis.
- mQ[VX] = ortho_axis.mV[VX];
- mQ[VY] = ortho_axis.mV[VY];
- mQ[VZ] = ortho_axis.mV[VZ];
- mQ[VW] = 0.f;
- }
- else
- {
- // a and b are NOT parallel or anti-parallel.
- // Return the rotation between these vectors.
- F32 theta = (F32)acos(cos_theta);
- setAngleAxis(theta, axis);
- }
- }
- // constrains rotation to a cone angle specified in radians
- const LLQuaternion &LLQuaternion::constrain(F32 radians)
- {
- const F32 cos_angle_lim = cosf( radians/2 ); // mQ[VW] limit
- const F32 sin_angle_lim = sinf( radians/2 ); // rotation axis length limit
- if (mQ[VW] < 0.f)
- {
- mQ[VX] *= -1.f;
- mQ[VY] *= -1.f;
- mQ[VZ] *= -1.f;
- mQ[VW] *= -1.f;
- }
- // if rotation angle is greater than limit (cos is less than limit)
- if( mQ[VW] < cos_angle_lim )
- {
- mQ[VW] = cos_angle_lim;
- F32 axis_len = sqrtf( mQ[VX]*mQ[VX] + mQ[VY]*mQ[VY] + mQ[VZ]*mQ[VZ] ); // sin(theta/2)
- F32 axis_mult_fact = sin_angle_lim / axis_len;
- mQ[VX] *= axis_mult_fact;
- mQ[VY] *= axis_mult_fact;
- mQ[VZ] *= axis_mult_fact;
- }
- return *this;
- }
- // Operators
- std::ostream& operator<<(std::ostream &s, const LLQuaternion &a)
- {
- s << "{ "
- << a.mQ[VX] << ", " << a.mQ[VY] << ", " << a.mQ[VZ] << ", " << a.mQ[VW]
- << " }";
- return s;
- }
- // Does NOT renormalize the result
- LLQuaternion operator*(const LLQuaternion &a, const LLQuaternion &b)
- {
- // LLQuaternion::mMultCount++;
- LLQuaternion q(
- b.mQ[3] * a.mQ[0] + b.mQ[0] * a.mQ[3] + b.mQ[1] * a.mQ[2] - b.mQ[2] * a.mQ[1],
- b.mQ[3] * a.mQ[1] + b.mQ[1] * a.mQ[3] + b.mQ[2] * a.mQ[0] - b.mQ[0] * a.mQ[2],
- b.mQ[3] * a.mQ[2] + b.mQ[2] * a.mQ[3] + b.mQ[0] * a.mQ[1] - b.mQ[1] * a.mQ[0],
- b.mQ[3] * a.mQ[3] - b.mQ[0] * a.mQ[0] - b.mQ[1] * a.mQ[1] - b.mQ[2] * a.mQ[2]
- );
- return q;
- }
- /*
- LLMatrix4 operator*(const LLMatrix4 &m, const LLQuaternion &q)
- {
- LLMatrix4 qmat(q);
- return (m*qmat);
- }
- */
- LLVector4 operator*(const LLVector4 &a, const LLQuaternion &rot)
- {
- F32 rw = - rot.mQ[VX] * a.mV[VX] - rot.mQ[VY] * a.mV[VY] - rot.mQ[VZ] * a.mV[VZ];
- F32 rx = rot.mQ[VW] * a.mV[VX] + rot.mQ[VY] * a.mV[VZ] - rot.mQ[VZ] * a.mV[VY];
- F32 ry = rot.mQ[VW] * a.mV[VY] + rot.mQ[VZ] * a.mV[VX] - rot.mQ[VX] * a.mV[VZ];
- F32 rz = rot.mQ[VW] * a.mV[VZ] + rot.mQ[VX] * a.mV[VY] - rot.mQ[VY] * a.mV[VX];
- F32 nx = - rw * rot.mQ[VX] + rx * rot.mQ[VW] - ry * rot.mQ[VZ] + rz * rot.mQ[VY];
- F32 ny = - rw * rot.mQ[VY] + ry * rot.mQ[VW] - rz * rot.mQ[VX] + rx * rot.mQ[VZ];
- F32 nz = - rw * rot.mQ[VZ] + rz * rot.mQ[VW] - rx * rot.mQ[VY] + ry * rot.mQ[VX];
- return LLVector4(nx, ny, nz, a.mV[VW]);
- }
- LLVector3 operator*(const LLVector3 &a, const LLQuaternion &rot)
- {
- F32 rw = - rot.mQ[VX] * a.mV[VX] - rot.mQ[VY] * a.mV[VY] - rot.mQ[VZ] * a.mV[VZ];
- F32 rx = rot.mQ[VW] * a.mV[VX] + rot.mQ[VY] * a.mV[VZ] - rot.mQ[VZ] * a.mV[VY];
- F32 ry = rot.mQ[VW] * a.mV[VY] + rot.mQ[VZ] * a.mV[VX] - rot.mQ[VX] * a.mV[VZ];
- F32 rz = rot.mQ[VW] * a.mV[VZ] + rot.mQ[VX] * a.mV[VY] - rot.mQ[VY] * a.mV[VX];
- F32 nx = - rw * rot.mQ[VX] + rx * rot.mQ[VW] - ry * rot.mQ[VZ] + rz * rot.mQ[VY];
- F32 ny = - rw * rot.mQ[VY] + ry * rot.mQ[VW] - rz * rot.mQ[VX] + rx * rot.mQ[VZ];
- F32 nz = - rw * rot.mQ[VZ] + rz * rot.mQ[VW] - rx * rot.mQ[VY] + ry * rot.mQ[VX];
- return LLVector3(nx, ny, nz);
- }
- LLVector3d operator*(const LLVector3d &a, const LLQuaternion &rot)
- {
- F64 rw = - rot.mQ[VX] * a.mdV[VX] - rot.mQ[VY] * a.mdV[VY] - rot.mQ[VZ] * a.mdV[VZ];
- F64 rx = rot.mQ[VW] * a.mdV[VX] + rot.mQ[VY] * a.mdV[VZ] - rot.mQ[VZ] * a.mdV[VY];
- F64 ry = rot.mQ[VW] * a.mdV[VY] + rot.mQ[VZ] * a.mdV[VX] - rot.mQ[VX] * a.mdV[VZ];
- F64 rz = rot.mQ[VW] * a.mdV[VZ] + rot.mQ[VX] * a.mdV[VY] - rot.mQ[VY] * a.mdV[VX];
- F64 nx = - rw * rot.mQ[VX] + rx * rot.mQ[VW] - ry * rot.mQ[VZ] + rz * rot.mQ[VY];
- F64 ny = - rw * rot.mQ[VY] + ry * rot.mQ[VW] - rz * rot.mQ[VX] + rx * rot.mQ[VZ];
- F64 nz = - rw * rot.mQ[VZ] + rz * rot.mQ[VW] - rx * rot.mQ[VY] + ry * rot.mQ[VX];
- return LLVector3d(nx, ny, nz);
- }
- F32 dot(const LLQuaternion &a, const LLQuaternion &b)
- {
- return a.mQ[VX] * b.mQ[VX] +
- a.mQ[VY] * b.mQ[VY] +
- a.mQ[VZ] * b.mQ[VZ] +
- a.mQ[VW] * b.mQ[VW];
- }
- // DEMO HACK: This lerp is probably inocrrect now due intermediate normalization
- // it should look more like the lerp below
- #if 0
- // linear interpolation
- LLQuaternion lerp(F32 t, const LLQuaternion &p, const LLQuaternion &q)
- {
- LLQuaternion r;
- r = t * (q - p) + p;
- r.normalize();
- return r;
- }
- #endif
- // lerp from identity to q
- LLQuaternion lerp(F32 t, const LLQuaternion &q)
- {
- LLQuaternion r;
- r.mQ[VX] = t * q.mQ[VX];
- r.mQ[VY] = t * q.mQ[VY];
- r.mQ[VZ] = t * q.mQ[VZ];
- r.mQ[VW] = t * (q.mQ[VZ] - 1.f) + 1.f;
- r.normalize();
- return r;
- }
- LLQuaternion lerp(F32 t, const LLQuaternion &p, const LLQuaternion &q)
- {
- LLQuaternion r;
- F32 inv_t;
- inv_t = 1.f - t;
- r.mQ[VX] = t * q.mQ[VX] + (inv_t * p.mQ[VX]);
- r.mQ[VY] = t * q.mQ[VY] + (inv_t * p.mQ[VY]);
- r.mQ[VZ] = t * q.mQ[VZ] + (inv_t * p.mQ[VZ]);
- r.mQ[VW] = t * q.mQ[VW] + (inv_t * p.mQ[VW]);
- r.normalize();
- return r;
- }
- // spherical linear interpolation
- LLQuaternion slerp( F32 u, const LLQuaternion &a, const LLQuaternion &b )
- {
- // cosine theta = dot product of a and b
- F32 cos_t = a.mQ[0]*b.mQ[0] + a.mQ[1]*b.mQ[1] + a.mQ[2]*b.mQ[2] + a.mQ[3]*b.mQ[3];
-
- // if b is on opposite hemisphere from a, use -a instead
- int bflip;
- if (cos_t < 0.0f)
- {
- cos_t = -cos_t;
- bflip = TRUE;
- }
- else
- bflip = FALSE;
- // if B is (within precision limits) the same as A,
- // just linear interpolate between A and B.
- F32 alpha; // interpolant
- F32 beta; // 1 - interpolant
- if (1.0f - cos_t < 0.00001f)
- {
- beta = 1.0f - u;
- alpha = u;
- }
- else
- {
- F32 theta = acosf(cos_t);
- F32 sin_t = sinf(theta);
- beta = sinf(theta - u*theta) / sin_t;
- alpha = sinf(u*theta) / sin_t;
- }
- if (bflip)
- beta = -beta;
- // interpolate
- LLQuaternion ret;
- ret.mQ[0] = beta*a.mQ[0] + alpha*b.mQ[0];
- ret.mQ[1] = beta*a.mQ[1] + alpha*b.mQ[1];
- ret.mQ[2] = beta*a.mQ[2] + alpha*b.mQ[2];
- ret.mQ[3] = beta*a.mQ[3] + alpha*b.mQ[3];
- return ret;
- }
- // lerp whenever possible
- LLQuaternion nlerp(F32 t, const LLQuaternion &a, const LLQuaternion &b)
- {
- if (dot(a, b) < 0.f)
- {
- return slerp(t, a, b);
- }
- else
- {
- return lerp(t, a, b);
- }
- }
- LLQuaternion nlerp(F32 t, const LLQuaternion &q)
- {
- if (q.mQ[VW] < 0.f)
- {
- return slerp(t, q);
- }
- else
- {
- return lerp(t, q);
- }
- }
- // slerp from identity quaternion to another quaternion
- LLQuaternion slerp(F32 t, const LLQuaternion &q)
- {
- F32 c = q.mQ[VW];
- if (1.0f == t || 1.0f == c)
- {
- // the trivial cases
- return q;
- }
- LLQuaternion r;
- F32 s, angle, stq, stp;
- s = (F32) sqrt(1.f - c*c);
- if (c < 0.0f)
- {
- // when c < 0.0 then theta > PI/2
- // since quat and -quat are the same rotation we invert one of
- // p or q to reduce unecessary spins
- // A equivalent way to do it is to convert acos(c) as if it had
- // been negative, and to negate stp
- angle = (F32) acos(-c);
- stp = -(F32) sin(angle * (1.f - t));
- stq = (F32) sin(angle * t);
- }
- else
- {
- angle = (F32) acos(c);
- stp = (F32) sin(angle * (1.f - t));
- stq = (F32) sin(angle * t);
- }
- r.mQ[VX] = (q.mQ[VX] * stq) / s;
- r.mQ[VY] = (q.mQ[VY] * stq) / s;
- r.mQ[VZ] = (q.mQ[VZ] * stq) / s;
- r.mQ[VW] = (stp + q.mQ[VW] * stq) / s;
- return r;
- }
- LLQuaternion mayaQ(F32 xRot, F32 yRot, F32 zRot, LLQuaternion::Order order)
- {
- LLQuaternion xQ( xRot*DEG_TO_RAD, LLVector3(1.0f, 0.0f, 0.0f) );
- LLQuaternion yQ( yRot*DEG_TO_RAD, LLVector3(0.0f, 1.0f, 0.0f) );
- LLQuaternion zQ( zRot*DEG_TO_RAD, LLVector3(0.0f, 0.0f, 1.0f) );
- LLQuaternion ret;
- switch( order )
- {
- case LLQuaternion::XYZ:
- ret = xQ * yQ * zQ;
- break;
- case LLQuaternion::YZX:
- ret = yQ * zQ * xQ;
- break;
- case LLQuaternion::ZXY:
- ret = zQ * xQ * yQ;
- break;
- case LLQuaternion::XZY:
- ret = xQ * zQ * yQ;
- break;
- case LLQuaternion::YXZ:
- ret = yQ * xQ * zQ;
- break;
- case LLQuaternion::ZYX:
- ret = zQ * yQ * xQ;
- break;
- }
- return ret;
- }
- const char *OrderToString( const LLQuaternion::Order order )
- {
- const char *p = NULL;
- switch( order )
- {
- default:
- case LLQuaternion::XYZ:
- p = "XYZ";
- break;
- case LLQuaternion::YZX:
- p = "YZX";
- break;
- case LLQuaternion::ZXY:
- p = "ZXY";
- break;
- case LLQuaternion::XZY:
- p = "XZY";
- break;
- case LLQuaternion::YXZ:
- p = "YXZ";
- break;
- case LLQuaternion::ZYX:
- p = "ZYX";
- break;
- }
- return p;
- }
- LLQuaternion::Order StringToOrder( const char *str )
- {
- if (strncmp(str, "XYZ", 3)==0 || strncmp(str, "xyz", 3)==0)
- return LLQuaternion::XYZ;
- if (strncmp(str, "YZX", 3)==0 || strncmp(str, "yzx", 3)==0)
- return LLQuaternion::YZX;
- if (strncmp(str, "ZXY", 3)==0 || strncmp(str, "zxy", 3)==0)
- return LLQuaternion::ZXY;
- if (strncmp(str, "XZY", 3)==0 || strncmp(str, "xzy", 3)==0)
- return LLQuaternion::XZY;
- if (strncmp(str, "YXZ", 3)==0 || strncmp(str, "yxz", 3)==0)
- return LLQuaternion::YXZ;
- if (strncmp(str, "ZYX", 3)==0 || strncmp(str, "zyx", 3)==0)
- return LLQuaternion::ZYX;
- return LLQuaternion::XYZ;
- }
- void LLQuaternion::getAngleAxis(F32* angle, LLVector3 &vec) const
- {
- F32 cos_a = mQ[VW];
- if (cos_a > 1.0f) cos_a = 1.0f;
- if (cos_a < -1.0f) cos_a = -1.0f;
- F32 sin_a = (F32) sqrt( 1.0f - cos_a * cos_a );
- if ( fabs( sin_a ) < 0.0005f )
- sin_a = 1.0f;
- else
- sin_a = 1.f/sin_a;
- F32 temp_angle = 2.0f * (F32) acos( cos_a );
- if (temp_angle > F_PI)
- {
- // The (angle,axis) pair should never have angles outside [PI, -PI]
- // since we want the _shortest_ (angle,axis) solution.
- // Since acos is defined for [0, PI], and we multiply by 2.0, we
- // can push the angle outside the acceptible range.
- // When this happens we set the angle to the other portion of a
- // full 2PI rotation, and negate the axis, which reverses the
- // direction of the rotation (by the right-hand rule).
- *angle = 2.f * F_PI - temp_angle;
- vec.mV[VX] = - mQ[VX] * sin_a;
- vec.mV[VY] = - mQ[VY] * sin_a;
- vec.mV[VZ] = - mQ[VZ] * sin_a;
- }
- else
- {
- *angle = temp_angle;
- vec.mV[VX] = mQ[VX] * sin_a;
- vec.mV[VY] = mQ[VY] * sin_a;
- vec.mV[VZ] = mQ[VZ] * sin_a;
- }
- }
- // quaternion does not need to be normalized
- void LLQuaternion::getEulerAngles(F32 *roll, F32 *pitch, F32 *yaw) const
- {
- LLMatrix3 rot_mat(*this);
- rot_mat.orthogonalize();
- rot_mat.getEulerAngles(roll, pitch, yaw);
- // // NOTE: LLQuaternion's are actually inverted with respect to
- // // the matrices, so this code also assumes inverted quaternions
- // // (-x, -y, -z, w). The result is that roll,pitch,yaw are applied
- // // in reverse order (yaw,pitch,roll).
- // F32 x = -mQ[VX], y = -mQ[VY], z = -mQ[VZ], w = mQ[VW];
- // F64 m20 = 2.0*(x*z-y*w);
- // if (1.0f - fabsf(m20) < F_APPROXIMATELY_ZERO)
- // {
- // *roll = 0.0f;
- // *pitch = (F32)asin(m20);
- // *yaw = (F32)atan2(2.0*(x*y-z*w), 1.0 - 2.0*(x*x+z*z));
- // }
- // else
- // {
- // *roll = (F32)atan2(-2.0*(y*z+x*w), 1.0-2.0*(x*x+y*y));
- // *pitch = (F32)asin(m20);
- // *yaw = (F32)atan2(-2.0*(x*y+z*w), 1.0-2.0*(y*y+z*z));
- // }
- }
- // Saves space by using the fact that our quaternions are normalized
- LLVector3 LLQuaternion::packToVector3() const
- {
- if( mQ[VW] >= 0 )
- {
- return LLVector3( mQ[VX], mQ[VY], mQ[VZ] );
- }
- else
- {
- return LLVector3( -mQ[VX], -mQ[VY], -mQ[VZ] );
- }
- }
- // Saves space by using the fact that our quaternions are normalized
- void LLQuaternion::unpackFromVector3( const LLVector3& vec )
- {
- mQ[VX] = vec.mV[VX];
- mQ[VY] = vec.mV[VY];
- mQ[VZ] = vec.mV[VZ];
- F32 t = 1.f - vec.magVecSquared();
- if( t > 0 )
- {
- mQ[VW] = sqrt( t );
- }
- else
- {
- // Need this to avoid trying to find the square root of a negative number due
- // to floating point error.
- mQ[VW] = 0;
- }
- }
- BOOL LLQuaternion::parseQuat(const std::string& buf, LLQuaternion* value)
- {
- if( buf.empty() || value == NULL)
- {
- return FALSE;
- }
- LLQuaternion quat;
- S32 count = sscanf( buf.c_str(), "%f %f %f %f", quat.mQ + 0, quat.mQ + 1, quat.mQ + 2, quat.mQ + 3 );
- if( 4 == count )
- {
- value->set( quat );
- return TRUE;
- }
- return FALSE;
- }
- // End