PK_ERROR_code_t PK_VERTEX_euler_merge_edges
(
--- received arguments ---
PK_VERTEX_t     vertex, --- Vertex to be deleted
PK_EDGE_t       edge    --- Edge to survive
)


This function deletes a vertex from an edge.


Specific Errors:
    PK_ERROR_bad_vertex    incorrect number of edges or isolated loops
                           at vertex
    PK_ERROR_bad_edge      edge is not connected to vertex


vertex must have exactly two oriented edges and no isolated loops.  The
edge argument indicates which of the two edges of the vertex is to survive.
The direction of edge after the operation remains unchanged.

If vertex is the vertex of a split ring then no edge will be deleted.

Any geometry on the deleted edge and vertex will be deleted and resulting body
will normally be invalid.

The inverse of this function is PK_EDGE_euler_split