Bifurcation diagram with two parameters

How we make bifurcation diagram of that function, There are two parameters in one dimensional: f[x_, a_,b_] := Piecewise[{{x (1 + a – ax), x <= 1/2}, {x (1 – b + bx), x > 1/2}}] a\in[0,1] and b\in [0,1]