Surface effective gravity of the meridian passing by the most distorted point of the star, its opposite, and the pole. The orange curve corresponds to the surface effective gravity given by the Roche model while the purple curve corresponds to the effective gravity obtained with our modelling. The system modelled here is a twin system composed of two 0.2 M_⊙ stars with an orbital separation of 2.8 R_1D. The absence of points near θ = 0 is explained by the Gauss-Legendre quadrature method that is not creating any points in this region of our grids. θ > 0 corresponds the direction where the stars are facing each other, while the direction θ < 0 corresponds to the back of the system.