Here we take a banana graph with 2 vertices and 3 edges. The integer `d' is the flow into the graph (and thus also the flow out at the other vertex). The base is (locally) affine space of dimension 3. We think of it as a toric variety, with fan the positive orthant in R^3 (a single cone).
The picture shows the fan of Mhat, a slice taken at x+y+z = 1 (because it is easier to draw in 3d). Thus the fan consists of the boundary of the positive orthant, together with a bunch of rays (1-dimensional cones), which appear as dots because we have taken this slice.
It would be nice to find a canonical way to compactify this. Compactification corresponds to cutting up the big triangle into convex polygons (ideally smaller triangles...) such that every green dot appears at a vertex. It is clear that it is possible to do this in an `ad hoc' way, but can it be made canonical?!
Sage code to produce these pictures is here
d=1:
d=2:
d=2#:
d=4:
d=5:
d=6:
d=7:
d=8:
d=9:
d=10:
d=11:
d=12:
d=13:
d=14:
d=15:
d=20:
d=25:
d=30: