PrimeWorldEditor/Common/CQuaternion.cpp

129 lines
3.2 KiB
C++

#include "CQuaternion.h"
#include <cmath>
#include <math.h>
CQuaternion::CQuaternion()
{
x = 0;
y = 0;
z = 0;
w = 0;
}
CQuaternion::CQuaternion(float _x, float _y, float _z, float _w)
{
x = _x;
y = _y;
z = _z;
w = _w;
}
CVector3f CQuaternion::XAxis()
{
return (*this * CVector3f::skUnitX);
}
CVector3f CQuaternion::YAxis()
{
return (*this * CVector3f::skUnitY);
}
CVector3f CQuaternion::ZAxis()
{
return (*this * CVector3f::skUnitZ);
}
CQuaternion CQuaternion::Inverse()
{
float fNorm = (w * w) + (x * x) + (y * y) + (z * z);
if (fNorm > 0.f)
{
float fInvNorm = 1.f / fNorm;
return CQuaternion(-x * fInvNorm, -y * fInvNorm, -z * fInvNorm, w * fInvNorm);
}
else
return CQuaternion::skZero;
}
// ************ OPERATORS ************
CVector3f CQuaternion::operator*(const CVector3f& vec) const
{
CVector3f uv, uuv;
CVector3f qvec(x, y, z);
uv = qvec.Cross(vec);
uuv = qvec.Cross(uv);
uv *= (2.0f * w);
uuv *= 2.0f;
return vec + uv + uuv;
}
CQuaternion CQuaternion::operator*(const CQuaternion& other) const
{
CQuaternion out;
out.x = ( x * other.w) + (y * other.z) - (z * other.y) + (w * other.x);
out.y = (-x * other.z) + (y * other.w) + (z * other.x) + (w * other.y);
out.z = ( x * other.y) - (y * other.x) + (z * other.w) + (w * other.z);
out.w = (-x * other.x) - (y * other.y) - (z * other.z) + (w * other.w);
return out;
}
void CQuaternion::operator *= (const CQuaternion& other)
{
*this = *this * other;
}
// ************ STATIC ************
CQuaternion CQuaternion::FromEuler(CVector3f euler)
{
/**
* The commented-out code below might be faster but the conversion isn't completely correct
* So in lieu of fixing it I'm using axis angles to convert from Eulers instead
* I'm not sure what the difference is performance-wise but the result is 100% accurate
*/
/*CQuaternion quat;
// Convert from degrees to radians
float pi = 3.14159265358979323846f;
euler = euler * pi / 180;
// Convert to quaternion
float c1 = cos(euler.x / 2);
float c2 = cos(euler.y / 2);
float c3 = cos(euler.z / 2);
float s1 = sin(euler.x / 2);
float s2 = sin(euler.y / 2);
float s3 = sin(euler.z / 2);
quat.w = (c1 * c2 * c3) - (s1 * s2 * s3);
quat.x = -((s1 * c2 * c3) + (c1 * s2 * s3));
quat.y = ((c1 * s2 * c3) - (s1 * c2 * s3));
quat.z = ((s1 * s2 * c3) + (c1 * c2 * s3));*/
CQuaternion x = CQuaternion::FromAxisAngle(euler.x, CVector3f(1,0,0));
CQuaternion y = CQuaternion::FromAxisAngle(euler.y, CVector3f(0,1,0));
CQuaternion z = CQuaternion::FromAxisAngle(euler.z, CVector3f(0,0,1));
CQuaternion quat = z * y * x;
return quat;
}
CQuaternion CQuaternion::FromAxisAngle(float angle, CVector3f axis)
{
CQuaternion quat;
axis = axis.Normalized();
angle = angle * 3.14159265358979323846f / 180;
float sa = sin(angle / 2);
quat.x = axis.x * sa;
quat.y = axis.y * sa;
quat.z = axis.z * sa;
quat.w = cos(angle / 2);
return quat;
}
CQuaternion CQuaternion::skIdentity = CQuaternion(0.f, 0.f, 0.f, 1.f);
CQuaternion CQuaternion::skZero = CQuaternion(0.f, 0.f, 0.f, 0.f);