public static F64Quat FromYawPitchRoll(F64 yaw_y, F64 pitch_x, F64 roll_z)
{
// Roll first, about axis the object is facing, then
// pitch upward, then yaw to face into the new heading
F64 half_roll = F64.Div2(roll_z);
F64 sr = F64.SinFastest(half_roll);
F64 cr = F64.CosFastest(half_roll);
F64 half_pitch = F64.Div2(pitch_x);
F64 sp = F64.SinFastest(half_pitch);
F64 cp = F64.CosFastest(half_pitch);
F64 half_yaw = F64.Div2(yaw_y);
F64 sy = F64.SinFastest(half_yaw);
F64 cy = F64.CosFastest(half_yaw);
return(new F64Quat(
cy * sp * cr + sy * cp * sr,
sy * cp * cr - cy * sp * sr,
cy * cp * sr - sy * sp * cr,
cy * cp * cr + sy * sp * sr));
}
public static F64Quat FromAxisAngle(F64Vec3 axis, F64 angle)
{
F64 half_angle = F64.Div2(angle);
return(new F64Quat(axis * F64.SinFastest(half_angle), F64.CosFastest(half_angle)));
}