set(cs->p_ext, i, j, k, P_EXT * dist);
set(cs->p_hum, i, j, k, P_HUM * (1.f - dist));
set(cs->p_act, i, j, k, P_ACT * (1.f - dist));
set(cs->p_ext, i, j, k, P_EXT * dist);
set(cs->p_hum, i, j, k, P_HUM * (1.f - dist));
set(cs->p_act, i, j, k, P_ACT * (1.f - dist));