How can I define a region that is bounded by a set of parametric curves?
E.g. three parametric curves - which are cubic Bezier curves - define the boundary of a shape:
cubicbez[a_, b_, c_, d_, t_] := (1 - t)^3*a + 3*(1 - t)^2*t*b + 3*(1 - t)*t^2*c + t^3*d bezierRegion[{a_, b_, c_, d_}] := ParametricRegion[cubicbez[a, b, c, d, t], {{t, 0, 1}}] regions = {bezierRegion[{{5, 5}, {10, 13}, {18, 4}, {20, 30}}], bezierRegion[{{20, 30}, {18, 40}, {17, 40}, {15, 35}}], bezierRegion[{{15, 35}, {25, 25}, {5, 20}, {5, 5}}]}; Show[Region /@ regions, Frame -> True] 
Is there a way to get the inside of that shape as a Mathematica region?
