| // Ceres Solver - A fast non-linear least squares minimizer |
| // Copyright 2019 Google Inc. All rights reserved. |
| // http://ceres-solver.org/ |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are met: |
| // |
| // * Redistributions of source code must retain the above copyright notice, |
| // this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above copyright notice, |
| // this list of conditions and the following disclaimer in the documentation |
| // and/or other materials provided with the distribution. |
| // * Neither the name of Google Inc. nor the names of its contributors may be |
| // used to endorse or promote products derived from this software without |
| // specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| // POSSIBILITY OF SUCH DAMAGE. |
| // |
| // Author: keir@google.com (Keir Mierle) |
| // sameeragarwal@google.com (Sameer Agarwal) |
| // |
| // Templated functions for manipulating rotations. The templated |
| // functions are useful when implementing functors for automatic |
| // differentiation. |
| // |
| // In the following, the Quaternions are laid out as 4-vectors, thus: |
| // |
| // q[0] scalar part. |
| // q[1] coefficient of i. |
| // q[2] coefficient of j. |
| // q[3] coefficient of k. |
| // |
| // where: i*i = j*j = k*k = -1 and i*j = k, j*k = i, k*i = j. |
| |
| #ifndef CERES_PUBLIC_ROTATION_H_ |
| #define CERES_PUBLIC_ROTATION_H_ |
| |
| #include <algorithm> |
| #include <cmath> |
| #include <limits> |
| #include "codegen/macros.h" |
| #include "glog/logging.h" |
| |
| namespace ceres { |
| |
| // Trivial wrapper to index linear arrays as matrices, given a fixed |
| // column and row stride. When an array "T* array" is wrapped by a |
| // |
| // (const) MatrixAdapter<T, row_stride, col_stride> M" |
| // |
| // the expression M(i, j) is equivalent to |
| // |
| // arrary[i * row_stride + j * col_stride] |
| // |
| // Conversion functions to and from rotation matrices accept |
| // MatrixAdapters to permit using row-major and column-major layouts, |
| // and rotation matrices embedded in larger matrices (such as a 3x4 |
| // projection matrix). |
| template <typename T, int row_stride, int col_stride> |
| struct MatrixAdapter; |
| |
| // Convenience functions to create a MatrixAdapter that treats the |
| // array pointed to by "pointer" as a 3x3 (contiguous) column-major or |
| // row-major matrix. |
| template <typename T> |
| MatrixAdapter<T, 1, 3> ColumnMajorAdapter3x3(T* pointer); |
| |
| template <typename T> |
| MatrixAdapter<T, 3, 1> RowMajorAdapter3x3(T* pointer); |
| |
| // Convert a value in combined axis-angle representation to a quaternion. |
| // The value angle_axis is a triple whose norm is an angle in radians, |
| // and whose direction is aligned with the axis of rotation, |
| // and quaternion is a 4-tuple that will contain the resulting quaternion. |
| // The implementation may be used with auto-differentiation up to the first |
| // derivative, higher derivatives may have unexpected results near the origin. |
| template <typename T> |
| void AngleAxisToQuaternion(const T* angle_axis, T* quaternion); |
| |
| // Convert a quaternion to the equivalent combined axis-angle representation. |
| // The value quaternion must be a unit quaternion - it is not normalized first, |
| // and angle_axis will be filled with a value whose norm is the angle of |
| // rotation in radians, and whose direction is the axis of rotation. |
| // The implementation may be used with auto-differentiation up to the first |
| // derivative, higher derivatives may have unexpected results near the origin. |
| template <typename T> |
| void QuaternionToAngleAxis(const T* quaternion, T* angle_axis); |
| |
| // Conversions between 3x3 rotation matrix (in column major order) and |
| // quaternion rotation representations. Templated for use with |
| // autodifferentiation. |
| template <typename T> |
| void RotationMatrixToQuaternion(const T* R, T* quaternion); |
| |
| template <typename T, int row_stride, int col_stride> |
| void RotationMatrixToQuaternion( |
| const MatrixAdapter<const T, row_stride, col_stride>& R, T* quaternion); |
| |
| // Conversions between 3x3 rotation matrix (in column major order) and |
| // axis-angle rotation representations. Templated for use with |
| // autodifferentiation. |
| template <typename T> |
| void RotationMatrixToAngleAxis(const T* R, T* angle_axis); |
| |
| template <typename T, int row_stride, int col_stride> |
| void RotationMatrixToAngleAxis( |
| const MatrixAdapter<const T, row_stride, col_stride>& R, T* angle_axis); |
| |
| template <typename T> |
| void AngleAxisToRotationMatrix(const T* angle_axis, T* R); |
| |
| template <typename T, int row_stride, int col_stride> |
| void AngleAxisToRotationMatrix( |
| const T* angle_axis, const MatrixAdapter<T, row_stride, col_stride>& R); |
| |
| // Conversions between 3x3 rotation matrix (in row major order) and |
| // Euler angle (in degrees) rotation representations. |
| // |
| // The {pitch,roll,yaw} Euler angles are rotations around the {x,y,z} |
| // axes, respectively. They are applied in that same order, so the |
| // total rotation R is Rz * Ry * Rx. |
| template <typename T> |
| void EulerAnglesToRotationMatrix(const T* euler, int row_stride, T* R); |
| |
| template <typename T, int row_stride, int col_stride> |
| void EulerAnglesToRotationMatrix( |
| const T* euler, const MatrixAdapter<T, row_stride, col_stride>& R); |
| |
| // Convert a 4-vector to a 3x3 scaled rotation matrix. |
| // |
| // The choice of rotation is such that the quaternion [1 0 0 0] goes to an |
| // identity matrix and for small a, b, c the quaternion [1 a b c] goes to |
| // the matrix |
| // |
| // [ 0 -c b ] |
| // I + 2 [ c 0 -a ] + higher order terms |
| // [ -b a 0 ] |
| // |
| // which corresponds to a Rodrigues approximation, the last matrix being |
| // the cross-product matrix of [a b c]. Together with the property that |
| // R(q1 * q2) = R(q1) * R(q2) this uniquely defines the mapping from q to R. |
| // |
| // No normalization of the quaternion is performed, i.e. |
| // R = ||q||^2 * Q, where Q is an orthonormal matrix |
| // such that det(Q) = 1 and Q*Q' = I |
| // |
| // WARNING: The rotation matrix is ROW MAJOR |
| template <typename T> |
| inline void QuaternionToScaledRotation(const T q[4], T R[3 * 3]); |
| |
| template <typename T, int row_stride, int col_stride> |
| inline void QuaternionToScaledRotation( |
| const T q[4], const MatrixAdapter<T, row_stride, col_stride>& R); |
| |
| // Same as above except that the rotation matrix is normalized by the |
| // Frobenius norm, so that R * R' = I (and det(R) = 1). |
| // |
| // WARNING: The rotation matrix is ROW MAJOR |
| template <typename T> |
| inline void QuaternionToRotation(const T q[4], T R[3 * 3]); |
| |
| template <typename T, int row_stride, int col_stride> |
| inline void QuaternionToRotation( |
| const T q[4], const MatrixAdapter<T, row_stride, col_stride>& R); |
| |
| // Rotates a point pt by a quaternion q: |
| // |
| // result = R(q) * pt |
| // |
| // Assumes the quaternion is unit norm. This assumption allows us to |
| // write the transform as (something)*pt + pt, as is clear from the |
| // formula below. If you pass in a quaternion with |q|^2 = 2 then you |
| // WILL NOT get back 2 times the result you get for a unit quaternion. |
| // |
| // Inplace rotation is not supported. pt and result must point to different |
| // memory locations, otherwise the result will be undefined. |
| template <typename T> |
| inline void UnitQuaternionRotatePoint(const T q[4], const T pt[3], T result[3]); |
| |
| // With this function you do not need to assume that q has unit norm. |
| // It does assume that the norm is non-zero. |
| // |
| // Inplace rotation is not supported. pt and result must point to different |
| // memory locations, otherwise the result will be undefined. |
| template <typename T> |
| inline void QuaternionRotatePoint(const T q[4], const T pt[3], T result[3]); |
| |
| // zw = z * w, where * is the Quaternion product between 4 vectors. |
| // |
| // Inplace quaternion product is not supported. The resulting quaternion zw must |
| // not share the memory with the input quaternion z and w, otherwise the result |
| // will be undefined. |
| template <typename T> |
| inline void QuaternionProduct(const T z[4], const T w[4], T zw[4]); |
| |
| // xy = x cross y; |
| // |
| // Inplace cross product is not supported. The resulting vector x_cross_y must |
| // not share the memory with the input vectors x and y, otherwise the result |
| // will be undefined. |
| template <typename T> |
| inline void CrossProduct(const T x[3], const T y[3], T x_cross_y[3]); |
| |
| template <typename T> |
| inline T DotProduct(const T x[3], const T y[3]); |
| |
| // y = R(angle_axis) * x; |
| // |
| // Inplace rotation is not supported. pt and result must point to different |
| // memory locations, otherwise the result will be undefined. |
| template <typename T> |
| inline void AngleAxisRotatePoint(const T angle_axis[3], |
| const T pt[3], |
| T result[3]); |
| |
| // --- IMPLEMENTATION |
| |
| template <typename T, int row_stride, int col_stride> |
| struct MatrixAdapter { |
| T* pointer_; |
| explicit MatrixAdapter(T* pointer) : pointer_(pointer) {} |
| |
| T& operator()(int r, int c) const { |
| return pointer_[r * row_stride + c * col_stride]; |
| } |
| }; |
| |
| template <typename T> |
| MatrixAdapter<T, 1, 3> ColumnMajorAdapter3x3(T* pointer) { |
| return MatrixAdapter<T, 1, 3>(pointer); |
| } |
| |
| template <typename T> |
| MatrixAdapter<T, 3, 1> RowMajorAdapter3x3(T* pointer) { |
| return MatrixAdapter<T, 3, 1>(pointer); |
| } |
| |
| template <typename T> |
| inline void AngleAxisToQuaternion(const T* angle_axis, T* quaternion) { |
| const T& a0 = angle_axis[0]; |
| const T& a1 = angle_axis[1]; |
| const T& a2 = angle_axis[2]; |
| const T theta_squared = a0 * a0 + a1 * a1 + a2 * a2; |
| |
| // For points not at the origin, the full conversion is numerically stable. |
| CERES_IF(theta_squared > T(0.0)) { |
| const T theta = sqrt(theta_squared); |
| const T half_theta = theta * T(0.5); |
| const T k = sin(half_theta) / theta; |
| quaternion[0] = cos(half_theta); |
| quaternion[1] = a0 * k; |
| quaternion[2] = a1 * k; |
| quaternion[3] = a2 * k; |
| } |
| CERES_ELSE { |
| // At the origin, sqrt() will produce NaN in the derivative since |
| // the argument is zero. By approximating with a Taylor series, |
| // and truncating at one term, the value and first derivatives will be |
| // computed correctly when Jets are used. |
| const T k(0.5); |
| quaternion[0] = T(1.0); |
| quaternion[1] = a0 * k; |
| quaternion[2] = a1 * k; |
| quaternion[3] = a2 * k; |
| } |
| CERES_ENDIF; |
| } |
| |
| template <typename T> |
| inline void QuaternionToAngleAxis(const T* quaternion, T* angle_axis) { |
| const T& q1 = quaternion[1]; |
| const T& q2 = quaternion[2]; |
| const T& q3 = quaternion[3]; |
| const T sin_squared_theta = q1 * q1 + q2 * q2 + q3 * q3; |
| |
| // For quaternions representing non-zero rotation, the conversion |
| // is numerically stable. |
| CERES_IF(sin_squared_theta > T(0.0)) { |
| const T sin_theta = sqrt(sin_squared_theta); |
| const T& cos_theta = quaternion[0]; |
| |
| // If cos_theta is negative, theta is greater than pi/2, which |
| // means that angle for the angle_axis vector which is 2 * theta |
| // would be greater than pi. |
| // |
| // While this will result in the correct rotation, it does not |
| // result in a normalized angle-axis vector. |
| // |
| // In that case we observe that 2 * theta ~ 2 * theta - 2 * pi, |
| // which is equivalent saying |
| // |
| // theta - pi = atan(sin(theta - pi), cos(theta - pi)) |
| // = atan(-sin(theta), -cos(theta)) |
| // |
| const T two_theta = T(2.0) * Ternary((cos_theta < T(0.0)), |
| atan2(-sin_theta, -cos_theta), |
| atan2(sin_theta, cos_theta)); |
| const T k = two_theta / sin_theta; |
| angle_axis[0] = q1 * k; |
| angle_axis[1] = q2 * k; |
| angle_axis[2] = q3 * k; |
| } |
| CERES_ELSE { |
| // For zero rotation, sqrt() will produce NaN in the derivative since |
| // the argument is zero. By approximating with a Taylor series, |
| // and truncating at one term, the value and first derivatives will be |
| // computed correctly when Jets are used. |
| const T k(2.0); |
| angle_axis[0] = q1 * k; |
| angle_axis[1] = q2 * k; |
| angle_axis[2] = q3 * k; |
| } |
| CERES_ENDIF; |
| } |
| |
| template <typename T> |
| void RotationMatrixToQuaternion(const T* R, T* angle_axis) { |
| RotationMatrixToQuaternion(ColumnMajorAdapter3x3(R), angle_axis); |
| } |
| |
| // This algorithm comes from "Quaternion Calculus and Fast Animation", |
| // Ken Shoemake, 1987 SIGGRAPH course notes |
| template <typename T, int row_stride, int col_stride> |
| void RotationMatrixToQuaternion( |
| const MatrixAdapter<const T, row_stride, col_stride>& R, T* quaternion) { |
| const T trace = R(0, 0) + R(1, 1) + R(2, 2); |
| if (trace >= 0.0) { |
| T t = sqrt(trace + T(1.0)); |
| quaternion[0] = T(0.5) * t; |
| t = T(0.5) / t; |
| quaternion[1] = (R(2, 1) - R(1, 2)) * t; |
| quaternion[2] = (R(0, 2) - R(2, 0)) * t; |
| quaternion[3] = (R(1, 0) - R(0, 1)) * t; |
| } else { |
| int i = 0; |
| if (R(1, 1) > R(0, 0)) { |
| i = 1; |
| } |
| |
| if (R(2, 2) > R(i, i)) { |
| i = 2; |
| } |
| |
| const int j = (i + 1) % 3; |
| const int k = (j + 1) % 3; |
| T t = sqrt(R(i, i) - R(j, j) - R(k, k) + T(1.0)); |
| quaternion[i + 1] = T(0.5) * t; |
| t = T(0.5) / t; |
| quaternion[0] = (R(k, j) - R(j, k)) * t; |
| quaternion[j + 1] = (R(j, i) + R(i, j)) * t; |
| quaternion[k + 1] = (R(k, i) + R(i, k)) * t; |
| } |
| } |
| |
| // The conversion of a rotation matrix to the angle-axis form is |
| // numerically problematic when then rotation angle is close to zero |
| // or to Pi. The following implementation detects when these two cases |
| // occurs and deals with them by taking code paths that are guaranteed |
| // to not perform division by a small number. |
| template <typename T> |
| inline void RotationMatrixToAngleAxis(const T* R, T* angle_axis) { |
| RotationMatrixToAngleAxis(ColumnMajorAdapter3x3(R), angle_axis); |
| } |
| |
| template <typename T, int row_stride, int col_stride> |
| void RotationMatrixToAngleAxis( |
| const MatrixAdapter<const T, row_stride, col_stride>& R, T* angle_axis) { |
| T quaternion[4]; |
| RotationMatrixToQuaternion(R, quaternion); |
| QuaternionToAngleAxis(quaternion, angle_axis); |
| return; |
| } |
| |
| template <typename T> |
| inline void AngleAxisToRotationMatrix(const T* angle_axis, T* R) { |
| AngleAxisToRotationMatrix(angle_axis, ColumnMajorAdapter3x3(R)); |
| } |
| |
| template <typename T, int row_stride, int col_stride> |
| void AngleAxisToRotationMatrix( |
| const T* angle_axis, const MatrixAdapter<T, row_stride, col_stride>& R) { |
| static const T kOne = T(1.0); |
| const T theta2 = DotProduct(angle_axis, angle_axis); |
| CERES_IF(theta2 > T(std::numeric_limits<double>::epsilon())) { |
| // We want to be careful to only evaluate the square root if the |
| // norm of the angle_axis vector is greater than zero. Otherwise |
| // we get a division by zero. |
| const T theta = sqrt(theta2); |
| const T wx = angle_axis[0] / theta; |
| const T wy = angle_axis[1] / theta; |
| const T wz = angle_axis[2] / theta; |
| |
| const T costheta = cos(theta); |
| const T sintheta = sin(theta); |
| |
| // clang-format off |
| R(0, 0) = costheta + wx*wx*(kOne - costheta); |
| R(1, 0) = wz*sintheta + wx*wy*(kOne - costheta); |
| R(2, 0) = -wy*sintheta + wx*wz*(kOne - costheta); |
| R(0, 1) = wx*wy*(kOne - costheta) - wz*sintheta; |
| R(1, 1) = costheta + wy*wy*(kOne - costheta); |
| R(2, 1) = wx*sintheta + wy*wz*(kOne - costheta); |
| R(0, 2) = wy*sintheta + wx*wz*(kOne - costheta); |
| R(1, 2) = -wx*sintheta + wy*wz*(kOne - costheta); |
| R(2, 2) = costheta + wz*wz*(kOne - costheta); |
| // clang-format on |
| } |
| CERES_ELSE { |
| // Near zero, we switch to using the first order Taylor expansion. |
| R(0, 0) = kOne; |
| R(1, 0) = angle_axis[2]; |
| R(2, 0) = -angle_axis[1]; |
| R(0, 1) = -angle_axis[2]; |
| R(1, 1) = kOne; |
| R(2, 1) = angle_axis[0]; |
| R(0, 2) = angle_axis[1]; |
| R(1, 2) = -angle_axis[0]; |
| R(2, 2) = kOne; |
| } |
| CERES_ENDIF; |
| } |
| |
| template <typename T> |
| inline void EulerAnglesToRotationMatrix(const T* euler, |
| const int row_stride_parameter, |
| T* R) { |
| EulerAnglesToRotationMatrix(euler, RowMajorAdapter3x3(R)); |
| } |
| |
| template <typename T, int row_stride, int col_stride> |
| void EulerAnglesToRotationMatrix( |
| const T* euler, const MatrixAdapter<T, row_stride, col_stride>& R) { |
| const double kPi = 3.14159265358979323846; |
| const T degrees_to_radians(kPi / 180.0); |
| |
| const T pitch(euler[0] * degrees_to_radians); |
| const T roll(euler[1] * degrees_to_radians); |
| const T yaw(euler[2] * degrees_to_radians); |
| |
| const T c1 = cos(yaw); |
| const T s1 = sin(yaw); |
| const T c2 = cos(roll); |
| const T s2 = sin(roll); |
| const T c3 = cos(pitch); |
| const T s3 = sin(pitch); |
| |
| R(0, 0) = c1 * c2; |
| R(0, 1) = -s1 * c3 + c1 * s2 * s3; |
| R(0, 2) = s1 * s3 + c1 * s2 * c3; |
| |
| R(1, 0) = s1 * c2; |
| R(1, 1) = c1 * c3 + s1 * s2 * s3; |
| R(1, 2) = -c1 * s3 + s1 * s2 * c3; |
| |
| R(2, 0) = -s2; |
| R(2, 1) = c2 * s3; |
| R(2, 2) = c2 * c3; |
| } |
| |
| template <typename T> |
| inline void QuaternionToScaledRotation(const T q[4], T R[3 * 3]) { |
| QuaternionToScaledRotation(q, RowMajorAdapter3x3(R)); |
| } |
| |
| template <typename T, int row_stride, int col_stride> |
| inline void QuaternionToScaledRotation( |
| const T q[4], const MatrixAdapter<T, row_stride, col_stride>& R) { |
| // Make convenient names for elements of q. |
| T a = q[0]; |
| T b = q[1]; |
| T c = q[2]; |
| T d = q[3]; |
| // This is not to eliminate common sub-expression, but to |
| // make the lines shorter so that they fit in 80 columns! |
| T aa = a * a; |
| T ab = a * b; |
| T ac = a * c; |
| T ad = a * d; |
| T bb = b * b; |
| T bc = b * c; |
| T bd = b * d; |
| T cc = c * c; |
| T cd = c * d; |
| T dd = d * d; |
| |
| // clang-format off |
| R(0, 0) = aa + bb - cc - dd; R(0, 1) = T(2) * (bc - ad); R(0, 2) = T(2) * (ac + bd); |
| R(1, 0) = T(2) * (ad + bc); R(1, 1) = aa - bb + cc - dd; R(1, 2) = T(2) * (cd - ab); |
| R(2, 0) = T(2) * (bd - ac); R(2, 1) = T(2) * (ab + cd); R(2, 2) = aa - bb - cc + dd; |
| // clang-format on |
| } |
| |
| template <typename T> |
| inline void QuaternionToRotation(const T q[4], T R[3 * 3]) { |
| QuaternionToRotation(q, RowMajorAdapter3x3(R)); |
| } |
| |
| template <typename T, int row_stride, int col_stride> |
| inline void QuaternionToRotation( |
| const T q[4], const MatrixAdapter<T, row_stride, col_stride>& R) { |
| QuaternionToScaledRotation(q, R); |
| |
| T normalizer = q[0] * q[0] + q[1] * q[1] + q[2] * q[2] + q[3] * q[3]; |
| normalizer = T(1) / normalizer; |
| |
| for (int i = 0; i < 3; ++i) { |
| for (int j = 0; j < 3; ++j) { |
| R(i, j) *= normalizer; |
| } |
| } |
| } |
| |
| template <typename T> |
| inline void UnitQuaternionRotatePoint(const T q[4], |
| const T pt[3], |
| T result[3]) { |
| DCHECK_NE(pt, result) << "Inplace rotation is not supported."; |
| |
| // clang-format off |
| const T t2 = q[0] * q[1]; |
| const T t3 = q[0] * q[2]; |
| const T t4 = q[0] * q[3]; |
| const T t5 = -q[1] * q[1]; |
| const T t6 = q[1] * q[2]; |
| const T t7 = q[1] * q[3]; |
| const T t8 = -q[2] * q[2]; |
| const T t9 = q[2] * q[3]; |
| const T t1 = -q[3] * q[3]; |
| result[0] = T(2) * ((t8 + t1) * pt[0] + (t6 - t4) * pt[1] + (t3 + t7) * pt[2]) + pt[0]; // NOLINT |
| result[1] = T(2) * ((t4 + t6) * pt[0] + (t5 + t1) * pt[1] + (t9 - t2) * pt[2]) + pt[1]; // NOLINT |
| result[2] = T(2) * ((t7 - t3) * pt[0] + (t2 + t9) * pt[1] + (t5 + t8) * pt[2]) + pt[2]; // NOLINT |
| // clang-format on |
| } |
| |
| template <typename T> |
| inline void QuaternionRotatePoint(const T q[4], const T pt[3], T result[3]) { |
| DCHECK_NE(pt, result) << "Inplace rotation is not supported."; |
| |
| // 'scale' is 1 / norm(q). |
| const T scale = |
| T(1) / sqrt(q[0] * q[0] + q[1] * q[1] + q[2] * q[2] + q[3] * q[3]); |
| |
| // Make unit-norm version of q. |
| const T unit[4] = { |
| scale * q[0], |
| scale * q[1], |
| scale * q[2], |
| scale * q[3], |
| }; |
| |
| UnitQuaternionRotatePoint(unit, pt, result); |
| } |
| |
| template <typename T> |
| inline void QuaternionProduct(const T z[4], const T w[4], T zw[4]) { |
| DCHECK_NE(z, zw) << "Inplace quaternion product is not supported."; |
| DCHECK_NE(w, zw) << "Inplace quaternion product is not supported."; |
| |
| // clang-format off |
| zw[0] = z[0] * w[0] - z[1] * w[1] - z[2] * w[2] - z[3] * w[3]; |
| zw[1] = z[0] * w[1] + z[1] * w[0] + z[2] * w[3] - z[3] * w[2]; |
| zw[2] = z[0] * w[2] - z[1] * w[3] + z[2] * w[0] + z[3] * w[1]; |
| zw[3] = z[0] * w[3] + z[1] * w[2] - z[2] * w[1] + z[3] * w[0]; |
| // clang-format on |
| } |
| |
| // xy = x cross y; |
| template <typename T> |
| inline void CrossProduct(const T x[3], const T y[3], T x_cross_y[3]) { |
| DCHECK_NE(x, x_cross_y) << "Inplace cross product is not supported."; |
| DCHECK_NE(y, x_cross_y) << "Inplace cross product is not supported."; |
| |
| x_cross_y[0] = x[1] * y[2] - x[2] * y[1]; |
| x_cross_y[1] = x[2] * y[0] - x[0] * y[2]; |
| x_cross_y[2] = x[0] * y[1] - x[1] * y[0]; |
| } |
| |
| template <typename T> |
| inline T DotProduct(const T x[3], const T y[3]) { |
| return (x[0] * y[0] + x[1] * y[1] + x[2] * y[2]); |
| } |
| |
| template <typename T> |
| inline void AngleAxisRotatePoint(const T angle_axis[3], |
| const T pt[3], |
| T result[3]) { |
| DCHECK_NE(pt, result) << "Inplace rotation is not supported."; |
| |
| const T theta2 = DotProduct(angle_axis, angle_axis); |
| CERES_IF(theta2 > T(std::numeric_limits<double>::epsilon())) { |
| // Away from zero, use the rodriguez formula |
| // |
| // result = pt costheta + |
| // (w x pt) * sintheta + |
| // w (w . pt) (1 - costheta) |
| // |
| // We want to be careful to only evaluate the square root if the |
| // norm of the angle_axis vector is greater than zero. Otherwise |
| // we get a division by zero. |
| // |
| const T theta = sqrt(theta2); |
| const T costheta = cos(theta); |
| const T sintheta = sin(theta); |
| const T theta_inverse = T(1.0) / theta; |
| |
| const T w[3] = {angle_axis[0] * theta_inverse, |
| angle_axis[1] * theta_inverse, |
| angle_axis[2] * theta_inverse}; |
| |
| // Explicitly inlined evaluation of the cross product for |
| // performance reasons. |
| const T w_cross_pt[3] = {w[1] * pt[2] - w[2] * pt[1], |
| w[2] * pt[0] - w[0] * pt[2], |
| w[0] * pt[1] - w[1] * pt[0]}; |
| const T tmp = |
| (w[0] * pt[0] + w[1] * pt[1] + w[2] * pt[2]) * (T(1.0) - costheta); |
| |
| result[0] = pt[0] * costheta + w_cross_pt[0] * sintheta + w[0] * tmp; |
| result[1] = pt[1] * costheta + w_cross_pt[1] * sintheta + w[1] * tmp; |
| result[2] = pt[2] * costheta + w_cross_pt[2] * sintheta + w[2] * tmp; |
| } |
| CERES_ELSE { |
| // Near zero, the first order Taylor approximation of the rotation |
| // matrix R corresponding to a vector w and angle w is |
| // |
| // R = I + hat(w) * sin(theta) |
| // |
| // But sintheta ~ theta and theta * w = angle_axis, which gives us |
| // |
| // R = I + hat(w) |
| // |
| // and actually performing multiplication with the point pt, gives us |
| // R * pt = pt + w x pt. |
| // |
| // Switching to the Taylor expansion near zero provides meaningful |
| // derivatives when evaluated using Jets. |
| // |
| // Explicitly inlined evaluation of the cross product for |
| // performance reasons. |
| const T w_cross_pt[3] = {angle_axis[1] * pt[2] - angle_axis[2] * pt[1], |
| angle_axis[2] * pt[0] - angle_axis[0] * pt[2], |
| angle_axis[0] * pt[1] - angle_axis[1] * pt[0]}; |
| |
| result[0] = pt[0] + w_cross_pt[0]; |
| result[1] = pt[1] + w_cross_pt[1]; |
| result[2] = pt[2] + w_cross_pt[2]; |
| } |
| CERES_ENDIF; |
| } |
| |
| } // namespace ceres |
| |
| #endif // CERES_PUBLIC_ROTATION_H_ |