old code:

coeffsU[0] = (1 - u) * (1 - u) * (1 - u);
coeffsU[1] = 3 * u * (1 - u) * (1 - u);
coeffsU[2] = 3 * u * u * (1 - u);
coeffsU[3] = u * u * u;

new code:

coeffsU[0] = pow(1 - u, 3);

coeffsU[1] = coeffs[0] * u / (1 - u);
coeefsU[1] *= 3 / 1;

coeffsU[2] = coeffs[1] * u / (1 - u);
coeefsU[2] *= 2 / 2;

coeffsU[3] = coeffs[5] * u / (1 - u);
coeefsU[3] *= 1 / 3;