public static SBSQuaternion Slerp(SBSQuaternion q0, SBSQuaternion q1, float t)
{
float w1 = q0.w, x1 = q0.x, y1 = q0.y, z1 = q0.z,
w2 = q1.w, x2 = q1.x, y2 = q1.y, z2 = q1.z,
dot = w1 * w2 + x1 * x2 + y1 * y2 + z1 * z2;
if (dot < 0.0f)
{
dot = -dot;
w2 = -w2;
x2 = -x2;
y2 = -y2;
z2 = -z2;
}
if (dot < 0.95f)
{
float angle = SBSMath.Acos(dot),
s = 1.0f / SBSMath.Sin(angle),
s1 = SBSMath.Sin(angle * (1.0f - t)) * s,
s2 = SBSMath.Sin(angle * t) * s;
w1 = w1 * s1 + w2 * s2;
x1 = x1 * s1 + x2 * s2;
y1 = y1 * s1 + y2 * s2;
z1 = z1 * s1 + z2 * s2;
}
else
{
w1 += t * (w2 - w1);
x1 += t * (x2 - x1);
y1 += t * (y2 - y1);
z1 += t * (z2 - z1);
float oom = x1 * x1 + y1 * y1 + z1 * z1 + w1 * w1;
if (oom < SBSMath.SqrEpsilon)
{
return(new SBSQuaternion(0.0f, 0.0f, 0.0f, 1.0f));
}
oom = 1.0f / SBSMath.Sqrt(oom);
x1 *= oom;
y1 *= oom;
z1 *= oom;
w1 *= oom;
}
return(new SBSQuaternion(x1, y1, z1, w1));
}
public static void Slerp(SBSQuaternion q0, SBSQuaternion q1, float t, out SBSQuaternion o)
#endif
{
float w1 = q0.w, x1 = q0.x, y1 = q0.y, z1 = q0.z,
w2 = q1.w, x2 = q1.x, y2 = q1.y, z2 = q1.z,
dot = w1 * w2 + x1 * x2 + y1 * y2 + z1 * z2;
if (dot < 0.0f)
{
dot = -dot;
w2 = -w2;
x2 = -x2;
y2 = -y2;
z2 = -z2;
}
if (dot < 0.95f)
{
float angle = SBSMath.Acos(dot),
s = 1.0f / SBSMath.Sin(angle),
s1 = SBSMath.Sin(angle * (1.0f - t)) * s,
s2 = SBSMath.Sin(angle * t) * s;
o.w = w1 * s1 + w2 * s2;
o.x = x1 * s1 + x2 * s2;
o.y = y1 * s1 + y2 * s2;
o.z = z1 * s1 + z2 * s2;
}
else
{
o.w = w1 + t * (w2 - w1);
o.x = x1 + t * (x2 - x1);
o.y = y1 + t * (y2 - y1);
o.z = z1 + t * (z2 - z1);
o.Normalize();
}
}
public static float Angle(SBSVector3 v0, SBSVector3 v1)
{
return(SBSMath.Acos(SBSVector3.Dot(v0.normalized, v1.normalized)) * SBSMath.ToDegrees);
}