private void Pop(cVertexList top)
{
//simulating a stack behavior for cVertexList list
//Pop procedure
cVertex last = new cVertex();
//last=top0.head.prev;
top.Delete(top.head.PrevVertex);
}
/*---------------------------------------------------------------------
* CleanVertices runs through the vertex list and deletes the
* vertices that are marked as processed but are not incident to any
* undeleted edges.
* ---------------------------------------------------------------------*/
protected void CleanVertices()
{
cEdge e;
cVertex v, t;
/* Mark all vertices incident to some undeleted edge as on the hull. */
e = Edges.head;
do
{
e.Endpts[0].IsOnHull = e.Endpts[1].IsOnHull = ONHULL;
e = e.next;
} while (e != Edges.head);
/* Delete all vertices that have been processed but
* are not on the hull. */
while (Vertices.head != null && Vertices.head.IsProcessed && !Vertices.head.IsOnHull)
{
v = Vertices.head;
Vertices.Delete(v);
}
v = Vertices.head.NextVertex;
do
{
if (v.IsProcessed && !v.IsOnHull)
{
t = v;
v = v.NextVertex;
Vertices.Delete(t);
}
else
{
v = v.NextVertex;
}
} while (v != Vertices.head);
/* Reset flags. */
v = Vertices.head;
do
{
v.Edge = null;
v.IsOnHull = !ONHULL;
v = v.NextVertex;
} while (v != Vertices.head);
}
/*---------------------------------------------------------------------
* Squash removes all elements from list marked delete.
* ---------------------------------------------------------------------*/
private void Squash()
{
cVertex v = new cVertex();
v = list.head;
for (i = 0; i < list.n; i++)
{
if (v.IsProcessed)
{
list.Delete(v);
}
v = v.NextVertex;
}
}