Assimp.Quaternion nlerp(Assimp.Quaternion a, Assimp.Quaternion b, float blend)
{
//cout << a.w + a.x + a.y + a.z << endl;
a.Normalize();
b.Normalize();
Assimp.Quaternion result;
float dot_product = a.X * b.X + a.Y * b.Y + a.Z * b.Z + a.W * b.W;
float one_minus_blend = 1.0f - blend;
if (dot_product < 0.0f)
{
result.X = a.X * one_minus_blend + blend * -b.X;
result.Y = a.Y * one_minus_blend + blend * -b.Y;
result.Z = a.Z * one_minus_blend + blend * -b.Z;
result.W = a.W * one_minus_blend + blend * -b.W;
}
else
{
result.X = a.X * one_minus_blend + blend * b.X;
result.Y = a.Y * one_minus_blend + blend * b.Y;
result.Z = a.Z * one_minus_blend + blend * b.Z;
result.W = a.W * one_minus_blend + blend * b.W;
}
result.Normalize();
return(result);
}
