Files
create/src/Base/DualQuaternion.h
2023-11-16 01:22:08 +01:00

152 lines
4.9 KiB
C++

/***************************************************************************
* Copyright (c) 2019 Viktor Titov (DeepSOIC) <vv.titov@gmail.com> *
* *
* This file is part of the FreeCAD CAx development system. *
* *
* This library is free software; you can redistribute it and/or *
* modify it under the terms of the GNU Library General Public *
* License as published by the Free Software Foundation; either *
* version 2 of the License, or (at your option) any later version. *
* *
* This library is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU Library General Public License for more details. *
* *
* You should have received a copy of the GNU Library General Public *
* License along with this library; see the file COPYING.LIB. If not, *
* write to the Free Software Foundation, Inc., 59 Temple Place, *
* Suite 330, Boston, MA 02111-1307, USA *
* *
***************************************************************************/
#ifndef FREECAD_BASE_DUAL_QUATERNION_H
#define FREECAD_BASE_DUAL_QUATERNION_H
#include "DualNumber.h"
#include <FCGlobal.h>
// NOLINTBEGIN(readability-identifier-length)
namespace Base
{
/**
* @brief The DualQuat class represents a dual quaternion, as a quaternion of
* dual number components. Dual quaternions are useful for placement
* interpolation, see pow method.
*
* Rotation is stored as non-dual part of DualQ. Translation is encoded into
* dual part of DualQuat:
* DualQuat.dual() = 0.5 * t * r,
* where t is quaternion with x,y,z of translation and w of 0, and r is the
* rotation quaternion.
*/
class BaseExport DualQuat
{
public:
DualNumber x;
DualNumber y;
DualNumber z;
DualNumber w;
public:
/// default constructor: init with zeros
DualQuat() = default;
DualQuat(DualNumber x, DualNumber y, DualNumber z, DualNumber w)
: x(x)
, y(y)
, z(z)
, w(w)
{}
DualQuat(double x, double y, double z, double w, double dx, double dy, double dz, double dw)
: x(x, dx)
, y(y, dy)
, z(z, dz)
, w(w, dw)
{}
DualQuat(double x, double y, double z, double w)
: x(x)
, y(y)
, z(z)
, w(w)
{}
/// Builds a dual quaternion from real and dual parts provided as pure real quaternions
DualQuat(DualQuat re, DualQuat du);
/// returns dual quaternion for identity placement
static DualQuat identity()
{
return {0.0, 0.0, 0.0, 1.0};
}
/// return a copy with dual part zeroed out
DualQuat real() const
{
return {x.re, y.re, z.re, w.re};
}
/// return a real-only quaternion made from dual part of this quaternion.
DualQuat dual() const
{
return {x.du, y.du, z.du, w.du};
}
/// conjugate
DualQuat conj() const
{
return {-x, -y, -z, w};
}
/// return vector part (with scalar part zeroed out)
DualQuat vec() const
{
return {x, y, z, 0.0};
}
/// magnitude of the quaternion
double length() const
{
return sqrt(x.re * x.re + y.re * y.re + z.re * z.re + w.re * w.re);
}
/// angle of rotation represented by this quaternion, in radians
double theta() const
{
return 2.0 * atan2(vec().length(), w.re);
}
/// dot product between real (rotation) parts of two dual quaternions (to determine if one of
/// them should be negated for shortest interpolation)
static double dot(DualQuat a, DualQuat b);
/// ScLERP. t=0.0 returns identity, t=1.0 returns this. t can also be outside of 0..1 bounds.
DualQuat pow(double t, bool shorten = true) const;
DualQuat operator-() const
{
return {-x, -y, -z, -w};
}
// DEBUG
// void print() const {
// Console().Log("%f, %f, %f, %f; %f, %f, %f, %f", x.re,y.re,z.re,w.re, x.du,y.du,z.du,
// w.du);
// }
};
BaseExport DualQuat operator+(DualQuat a, DualQuat b);
BaseExport DualQuat operator-(DualQuat a, DualQuat b);
BaseExport DualQuat operator*(DualQuat a, DualQuat b);
BaseExport DualQuat operator*(DualQuat a, double b);
BaseExport DualQuat operator*(double a, DualQuat b);
BaseExport DualQuat operator*(DualQuat a, DualNumber b);
BaseExport DualQuat operator*(DualNumber a, DualQuat b);
} // namespace Base
// NOLINTEND(readability-identifier-length)
#endif