Mesh Library - Vertex

struct vertex{

	Id        vertexno;
	HalfEdge  *vedge;
        double    gauss_cur;
	double    vcoord[3];
        double    ncoord[3];

	Vertex    *next;
	Vertex    *prev;

	int      alivev;
};

• vertexno - Id of current vertex
• vedge - the halfedge , which has current vertex as starting vertex
• gauss_cur - gaussian curvature of current vertex
• vcoord - coordinates of the vertex
• ncoord - coordinates of the normal attached to the vertex
• next,prev - vertex pointers in vertex list, no geometric meaning
• alivev - indicating if the vertex is alive

• Id VertexIDReset();
  During the construction of vertex list, a static in variable is used to indicating the Ids of vertices. After the construction of the vertex list, call this function to reset this static variable.

• void VertexConstruct( Solid ** s, double x, double y, double z );
  Construct a vertex with coordinates (x,y,z) and add it to the vertex list of solid s.

• oid VertexConstructN( Solid ** s, double x, double y, double z,double nx , double ny, double nz);
  Construct a vertex with coordinates (x,y,z) and normal (nx,ny,nz), and add it to the vertex list of sold s.

• void VertexDestruct( Vertex ** v);
  Desctruct the vertex v

• HalfEdge * VertexFirstOutHalfEdge( Vertex * v);
  Return the first halfedge issuing out from vertex v.

• HalfEdge * VertexNextOutHalfEdge( HalfEdge * h);
  Return the adjacent halfedge r of h, such that r and h shares the same starting vertex, and the rotation from h to r is ccw
  
• HalfEdge * VertexFirstInHalfEdge( Vertex * v);
  Return the first halfedge entering vertex v

• HalfEdge * VertexNextInHalfEdge( HalfEdge * h);
  Return the adjacent halfedge r of h, such that r and h shares the same ending vertex, and the rotation from h to r is ccw
  
• Face * VertexFirstFace( Vertex * v );
  Find the first face attached to v

• Face * VertexNextFace( Vertex * v , Face * f );
  Find the next face g attached to v, the rotation from f to g is ccw
  
• Vertex * VertexFirstVertex( Vertex * v);
  Return the first vertex attached to vertex

• Vertex * VertexNextVertex( Vertex * v, Vertex * w);
  W is a vertex attached to vertex v.Return the next vertex u attached to vertex v, (u,v,w) is ccw

• void VertexCheckConsistency( Vertex * v);
  Check if vertex v is convex locally.

• int VertexCheckNeighorConvexity( Vertex * v);
  Check if the neighborhood of vertex v is consistent with manifold structure