Figure 4.2: (a) Tangentially and (b) tangent cone graph-like Figure 4.3: (a) The square is not graph-like with the indicated radius (no orientation makes it a graph). (b) The rounded rectangle is graph-like but not tangentially graph- like with the indicated center and radius. 84 γ ( s ) (a) γ ( s ) (b) γ (a) γ (b)