diff options
Diffstat (limited to 'indra/llmath/llquaternion.cpp')
-rwxr-xr-x | indra/llmath/llquaternion.cpp | 449 |
1 files changed, 225 insertions, 224 deletions
diff --git a/indra/llmath/llquaternion.cpp b/indra/llmath/llquaternion.cpp index 7381d5eb99..47374c287f 100755 --- a/indra/llmath/llquaternion.cpp +++ b/indra/llmath/llquaternion.cpp @@ -1,4 +1,4 @@ -/** +/** * @file llquaternion.cpp * @brief LLQuaternion class implementation. * @@ -58,34 +58,40 @@ LLQuaternion::LLQuaternion(const LLMatrix3 &mat) 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(); + F32 mag = sqrtf(vec.mV[VX] * vec.mV[VX] + vec.mV[VY] * vec.mV[VY] + vec.mV[VZ] * vec.mV[VZ]); + if (mag > FP_MAG_THRESHOLD) + { + angle *= 0.5; + F32 c = cosf(angle); + F32 s = sinf(angle) / mag; + mQ[VX] = vec.mV[VX] * s; + mQ[VY] = vec.mV[VY] * s; + mQ[VZ] = vec.mV[VZ] * s; + mQ[VW] = c; + } + else + { + loadIdentity(); + } } 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(); + F32 mag = sqrtf(vec.mV[VX] * vec.mV[VX] + vec.mV[VY] * vec.mV[VY] + vec.mV[VZ] * vec.mV[VZ]); + if (mag > FP_MAG_THRESHOLD) + { + angle *= 0.5; + F32 c = cosf(angle); + F32 s = sinf(angle) / mag; + mQ[VX] = vec.mV[VX] * s; + mQ[VY] = vec.mV[VY] * s; + mQ[VZ] = vec.mV[VZ] * s; + mQ[VW] = c; + } + else + { + loadIdentity(); + } } LLQuaternion::LLQuaternion(const LLVector3 &x_axis, @@ -136,57 +142,61 @@ void LLQuaternion::quantize8(F32 lower, F32 upper) 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(); + F32 mag = sqrtf(x * x + y * y + z * z); + if (mag > FP_MAG_THRESHOLD) + { + angle *= 0.5; + F32 c = cosf(angle); + F32 s = sinf(angle) / mag; + mQ[VX] = x * s; + mQ[VY] = y * s; + mQ[VZ] = z * s; + mQ[VW] = c; + } + else + { + loadIdentity(); + } 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(); + F32 mag = sqrtf(vec.mV[VX] * vec.mV[VX] + vec.mV[VY] * vec.mV[VY] + vec.mV[VZ] * vec.mV[VZ]); + if (mag > FP_MAG_THRESHOLD) + { + angle *= 0.5; + F32 c = cosf(angle); + F32 s = sinf(angle) / mag; + mQ[VX] = vec.mV[VX] * s; + mQ[VY] = vec.mV[VY] * s; + mQ[VZ] = vec.mV[VZ] * s; + mQ[VW] = c; + } + else + { + loadIdentity(); + } 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(); + F32 mag = sqrtf(vec.mV[VX] * vec.mV[VX] + vec.mV[VY] * vec.mV[VY] + vec.mV[VZ] * vec.mV[VZ]); + if (mag > FP_MAG_THRESHOLD) + { + angle *= 0.5; + F32 c = cosf(angle); + F32 s = sinf(angle) / mag; + mQ[VX] = vec.mV[VX] * s; + mQ[VY] = vec.mV[VY] * s; + mQ[VZ] = vec.mV[VZ] * s; + mQ[VW] = c; + } + else + { + loadIdentity(); + } return (*this); } @@ -219,68 +229,80 @@ const LLQuaternion& LLQuaternion::set(const LLMatrix4 &mat) // 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(); + F32 mag = sqrtf(x * x + y * y + z * z); + if (mag > FP_MAG_THRESHOLD) + { + angle *= 0.5; + F32 c = cosf(angle); + F32 s = sinf(angle) / mag; + mQ[VX] = x * s; + mQ[VY] = y * s; + mQ[VZ] = z * s; + mQ[VW] = c; + } + else + { + loadIdentity(); + } 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(); + F32 mag = sqrtf(vec.mV[VX] * vec.mV[VX] + vec.mV[VY] * vec.mV[VY] + vec.mV[VZ] * vec.mV[VZ]); + if (mag > FP_MAG_THRESHOLD) + { + angle *= 0.5; + F32 c = cosf(angle); + F32 s = sinf(angle) / mag; + mQ[VX] = vec.mV[VX] * s; + mQ[VY] = vec.mV[VY] * s; + mQ[VZ] = vec.mV[VZ] * s; + mQ[VW] = c; + } + else + { + loadIdentity(); + } 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(); + F32 mag = sqrtf(vec.mV[VX] * vec.mV[VX] + vec.mV[VY] * vec.mV[VY] + vec.mV[VZ] * vec.mV[VZ]); + if (mag > FP_MAG_THRESHOLD) + { + angle *= 0.5; + F32 c = cosf(angle); + F32 s = sinf(angle) / mag; + mQ[VX] = vec.mV[VX] * s; + mQ[VY] = vec.mV[VY] * s; + mQ[VZ] = vec.mV[VZ] * s; + mQ[VW] = c; + } + else + { + loadIdentity(); + } 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(); + roll *= 0.5f; + pitch *= 0.5f; + yaw *= 0.5f; + F32 sinX = sinf(roll); + F32 cosX = cosf(roll); + F32 sinY = sinf(pitch); + F32 cosY = cosf(pitch); + F32 sinZ = sinf(yaw); + F32 cosZ = cosf(yaw); + mQ[VW] = cosX * cosY * cosZ - sinX * sinY * sinZ; + mQ[VX] = sinX * cosY * cosZ + cosX * sinY * sinZ; + mQ[VY] = cosX * sinY * cosZ - sinX * cosY * sinZ; + mQ[VZ] = cosX * cosY * sinZ + sinX * sinY * cosZ; return (*this); } @@ -425,68 +447,44 @@ LLMatrix4 LLQuaternion::getMatrix4(void) const // 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) + F32 ab = a * b; // dotproduct + LLVector3 c = a % b; // crossproduct + F32 cc = c * c; // squared length of the crossproduct + if (ab * ab + cc) // test if the arguments have sufficient magnitude { - // 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) + if (cc > 0.0f) // test if the arguments are (anti)parallel { - // Use the z-axis instead. - ortho_axis.setVec(0.f, 0.f, 1.f); + F32 s = sqrtf(ab * ab + cc) + ab; // note: don't try to optimize this line + F32 m = 1.0f / sqrtf(cc + s * s); // the inverted magnitude of the quaternion + mQ[VX] = c.mV[VX] * m; + mQ[VY] = c.mV[VY] * m; + mQ[VZ] = c.mV[VZ] * m; + mQ[VW] = s * m; + return; + } + if (ab < 0.0f) // test if the angle is bigger than PI/2 (anti parallel) + { + c = a - b; // the arguments are anti-parallel, we have to choose an axis + F32 m = sqrtf(c.mV[VX] * c.mV[VX] + c.mV[VY] * c.mV[VY]); // the length projected on the XY-plane + if (m > FP_MAG_THRESHOLD) + { + mQ[VX] = -c.mV[VY] / m; // return the quaternion with the axis in the XY-plane + mQ[VY] = c.mV[VX] / m; + mQ[VZ] = 0.0f; + mQ[VW] = 0.0f; + return; + } + else // the vectors are parallel to the Z-axis + { + mQ[VX] = 1.0f; // rotate around the X-axis + mQ[VY] = 0.0f; + mQ[VZ] = 0.0f; + mQ[VW] = 0.0f; + return; + } } - - // 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); } + loadIdentity(); } // constrains rotation to a cone angle specified in radians @@ -838,79 +836,82 @@ LLQuaternion::Order StringToOrder( const char *str ) 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; + F32 v = sqrtf(mQ[VX] * mQ[VX] + mQ[VY] * mQ[VY] + mQ[VZ] * mQ[VZ]); // length of the vector-component + if (v > FP_MAG_THRESHOLD) + { + F32 oomag = 1.0f / v; + F32 w = mQ[VW]; + if (mQ[VW] < 0.0f) + { + w = -w; // make VW positive + oomag = -oomag; // invert the axis + } + vec.mV[VX] = mQ[VX] * oomag; // normalize the axis + vec.mV[VY] = mQ[VY] * oomag; + vec.mV[VZ] = mQ[VZ] * oomag; + *angle = 2.0f * atan2f(v, w); // get the angle } 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; + *angle = 0.0f; // no rotation + vec.mV[VX] = 0.0f; // around some dummy axis + vec.mV[VY] = 0.0f; + vec.mV[VZ] = 1.0f; } } - // 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)); -// } + F32 sx = 2 * (mQ[VX] * mQ[VW] - mQ[VY] * mQ[VZ]); // sine of the roll + F32 sy = 2 * (mQ[VY] * mQ[VW] + mQ[VX] * mQ[VZ]); // sine of the pitch + F32 ys = mQ[VW] * mQ[VW] - mQ[VY] * mQ[VY]; // intermediate cosine 1 + F32 xz = mQ[VX] * mQ[VX] - mQ[VZ] * mQ[VZ]; // intermediate cosine 2 + F32 cx = ys - xz; // cosine of the roll + F32 cy = sqrtf(sx * sx + cx * cx); // cosine of the pitch + if (cy > GIMBAL_THRESHOLD) // no gimbal lock + { + *roll = atan2f(sx, cx); + *pitch = atan2f(sy, cy); + *yaw = atan2f(2 * (mQ[VZ] * mQ[VW] - mQ[VX] * mQ[VY]), ys + xz); + } + else // gimbal lock + { + if (sy > 0) + { + *pitch = F_PI_BY_TWO; + *yaw = 2 * atan2f(mQ[VZ] + mQ[VX], mQ[VW] + mQ[VY]); + } + else + { + *pitch = -F_PI_BY_TWO; + *yaw = 2 * atan2f(mQ[VZ] - mQ[VX], mQ[VW] - mQ[VY]); + } + *roll = 0; + } } // Saves space by using the fact that our quaternions are normalized LLVector3 LLQuaternion::packToVector3() const { + F32 x = mQ[VX]; + F32 y = mQ[VY]; + F32 z = mQ[VZ]; + F32 w = mQ[VW]; + F32 mag = sqrtf(x * x + y * y + z * z + w * w); + if (mag > FP_MAG_THRESHOLD) + { + x /= mag; + y /= mag; + z /= mag; // no need to normalize w, it's not used + } if( mQ[VW] >= 0 ) { - return LLVector3( mQ[VX], mQ[VY], mQ[VZ] ); + return LLVector3( x, y , z ); } else { - return LLVector3( -mQ[VX], -mQ[VY], -mQ[VZ] ); + return LLVector3( -x, -y, -z ); } } |