Files
Vector3D/src/Quaternion.cpp
2025-04-09 18:41:45 -04:00

120 lines
3.6 KiB
C++

#include "Quaternion.h"
#include <cmath>
/**
* @brief Create a quaternion from an angle and axis
* @param angle The angle to rotate by
* @param axis The axis to rotate around
*/
Quaternion Quaternion::FromAngleAndAxis(float angle, const Matrix<1, 3> &axis)
{
const float halfAngle = angle / 2;
const float sinHalfAngle = sin(halfAngle);
Matrix<1, 3> normalizedAxis{};
axis.Normalize(normalizedAxis);
return Quaternion{
static_cast<float>(cos(halfAngle)),
normalizedAxis.Get(0, 0) * sinHalfAngle,
normalizedAxis.Get(0, 1) * sinHalfAngle,
normalizedAxis.Get(0, 2) * sinHalfAngle};
}
float Quaternion::operator[](uint8_t index) const
{
if (index < 4)
{
return this->matrix[index];
}
// index out of bounds
return 1e+6;
}
void Quaternion::operator=(const Quaternion &other)
{
memcpy(&(this->matrix), &(other.matrix), 4 * sizeof(float));
}
Quaternion Quaternion::operator*(const Quaternion &other) const
{
Quaternion result{};
this->Q_Mult(other, result);
return result;
}
Quaternion Quaternion::operator*(float scalar) const
{
return Quaternion{this->w * scalar, this->v1 * scalar, this->v2 * scalar, this->v3 * scalar};
}
Quaternion Quaternion::operator+(const Quaternion &other) const
{
return Quaternion{this->w + other.w, this->v1 + other.v1, this->v2 + other.v2, this->v3 + other.v3};
}
Quaternion &
Quaternion::Q_Mult(const Quaternion &other, Quaternion &buffer) const
{
// eq. 6
buffer.w = (other.w * this->w - other.v1 * this->v1 - other.v2 * this->v2 - other.v3 * this->v3);
buffer.v1 = (other.w * this->v1 + other.v1 * this->w - other.v2 * this->v3 + other.v3 * this->v2);
buffer.v2 = (other.w * this->v2 + other.v1 * this->v3 + other.v2 * this->w - other.v3 * this->v1);
buffer.v3 = (other.w * this->v3 - other.v1 * this->v2 + other.v2 * this->v1 + other.v3 * this->w);
return buffer;
}
Quaternion &Quaternion::Rotate(Quaternion &other, Quaternion &buffer) const
{
Quaternion prime{this->w, -this->v1, -this->v2, -this->v3};
buffer.v1 = other.v1;
buffer.v2 = other.v2;
buffer.v3 = other.v3;
buffer.w = 0;
Quaternion temp{};
this->Q_Mult(buffer, temp);
temp.Q_Mult(prime, buffer);
return buffer;
}
void Quaternion::Normalize()
{
float magnitude = sqrt(this->v1 * this->v1 + this->v2 * this->v2 + this->v3 * this->v3 + this->w * this->w);
if (magnitude == 0)
{
return;
}
this->v1 /= magnitude;
this->v2 /= magnitude;
this->v3 /= magnitude;
this->w /= magnitude;
}
Matrix<3, 3> Quaternion::ToRotationMatrix() const
{
float xx = this->v1 * this->v1;
float yy = this->v2 * this->v2;
float zz = this->v3 * this->v3;
Matrix<3, 3> rotationMatrix{
1 - 2 * (yy - zz), 2 * (this->v1 * this->v2 - this->v3 * this->w), 2 * (this->v1 * this->v3 + this->v2 * this->w),
2 * (this->v1 * this->v2 + this->v3 * this->w), 1 - 2 * (xx - zz), 2 * (this->v2 * this->v3 - this->v1 * this->w),
2 * (this->v1 * this->v3 - this->v2 * this->w), 2 * (this->v2 * this->v3 + this->v1 * this->w), 1 - 2 * (xx - yy)};
return rotationMatrix;
};
Matrix<3, 1> Quaternion::ToEulerAngle() const
{
float sqv1 = this->v1 * this->v1;
float sqv2 = this->v2 * this->v2;
float sqv3 = this->v3 * this->v3;
float sqw = this->w * this->w;
Matrix<3, 1> eulerAngle;
{
atan2(2.0 * (this->v1 * this->v2 + this->v3 * this->w), (sqv1 - sqv2 - sqv3 + sqw));
asin(-2.0 * (this->v1 * this->v3 - this->v2 * this->w) / (sqv1 + sqv2 + sqv3 + sqw));
atan2(2.0 * (this->v2 * this->v3 + this->v1 * this->w), (-sqv1 - sqv2 + sqv3 + sqw));
};
return eulerAngle;
}