Well, yes, I'm afraid we don't have a Z-buffer so sorting must be dealt with
a good balance of design (triangulation) and use of tricks in the
development side. Its useful to understand how the sorting algorithm works:
for each triangle the mid point is calculated and the projection of this
vertex to the camera is used to "sort" the triangles in a painter algorithm.
With this in mind, one can begin to understand why an elongated or thin
triangle can produce a mid point projection that is not really representing
the surface of the triangle in a good way.
