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701 lines
19 KiB
701 lines
19 KiB
/*
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** Copyright 1994, Silicon Graphics, Inc.
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** All Rights Reserved.
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**
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** This is UNPUBLISHED PROPRIETARY SOURCE CODE of Silicon Graphics, Inc.;
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** the contents of this file may not be disclosed to third parties, copied or
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** duplicated in any form, in whole or in part, without the prior written
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** permission of Silicon Graphics, Inc.
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**
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** RESTRICTED RIGHTS LEGEND:
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** Use, duplication or disclosure by the Government is subject to restrictions
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** as set forth in subdivision (c)(1)(ii) of the Rights in Technical Data
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** and Computer Software clause at DFARS 252.227-7013, and/or in similar or
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** successor clauses in the FAR, DOD or NASA FAR Supplement. Unpublished -
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** rights reserved under the Copyright Laws of the United States.
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**
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** Author: Eric Veach, July 1994.
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*/
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#include <assert.h>
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#include "mesh.h"
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#include "memalloc.h"
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#define TRUE 1
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#define FALSE 0
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/************************ Utility Routines ************************/
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/* Allocate and free half-edges in pairs for efficiency.
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* The *only* place that should use this fact is allocation/free.
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*/
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typedef struct { GLUhalfEdge e, eSym; } EdgePair;
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/* MakeEdge creates a new pair of half-edges which form their own loop.
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* No vertex or face structures are allocated, but these must be assigned
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* before the current edge operation is completed.
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*/
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static GLUhalfEdge *MakeEdge( GLUhalfEdge *eNext )
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{
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EdgePair *pair = (EdgePair *)memAlloc( sizeof( EdgePair ));
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GLUhalfEdge *e = &pair->e;
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GLUhalfEdge *eSym = &pair->eSym;
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GLUhalfEdge *ePrev;
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/* Make sure eNext points to the first edge of the edge pair */
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if( eNext->Sym < eNext ) { eNext = eNext->Sym; }
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/* Insert in circular doubly-linked list before eNext.
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* Note that the prev pointer is stored in Sym->next.
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*/
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ePrev = eNext->Sym->next;
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eSym->next = ePrev;
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ePrev->Sym->next = e;
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e->next = eNext;
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eNext->Sym->next = eSym;
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e->Sym = eSym;
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e->Onext = e;
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e->Lnext = eSym;
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e->Org = NULL;
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e->Lface = NULL;
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e->winding = 0;
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e->activeRegion = NULL;
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eSym->Sym = e;
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eSym->Onext = eSym;
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eSym->Lnext = e;
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eSym->Org = NULL;
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eSym->Lface = NULL;
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eSym->winding = 0;
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eSym->activeRegion = NULL;
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return e;
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}
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/* Splice( a, b ) is best described by the Guibas/Stolfi paper or the
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* CS348a notes (see mesh.h). Basically it modifies the mesh so that
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* a->Onext and b->Onext are exchanged. This can have various effects
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* depending on whether a and b belong to different face or vertex rings.
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* For more explanation see __gl_meshSplice() below.
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*/
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static void Splice( GLUhalfEdge *a, GLUhalfEdge *b )
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{
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GLUhalfEdge *aOnext = a->Onext;
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GLUhalfEdge *bOnext = b->Onext;
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aOnext->Sym->Lnext = b;
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bOnext->Sym->Lnext = a;
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a->Onext = bOnext;
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b->Onext = aOnext;
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}
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/* MakeVertex( eOrig, vNext ) creates a new vertex and makes it the origin
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* of all edges in the vertex loop to which eOrig belongs. "vNext" gives
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* a place to insert the new vertex in the global vertex list. We insert
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* the new vertex *before* vNext so that algorithms which walk the vertex
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* list will not see the newly created vertices.
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*/
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static void MakeVertex( GLUhalfEdge *eOrig, GLUvertex *vNext )
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{
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GLUvertex *vNew = (GLUvertex *)memAlloc( sizeof( GLUvertex ));
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GLUhalfEdge *e;
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GLUvertex *vPrev;
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/* insert in circular doubly-linked list before vNext */
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vPrev = vNext->prev;
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vNew->prev = vPrev;
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vPrev->next = vNew;
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vNew->next = vNext;
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vNext->prev = vNew;
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vNew->anEdge = eOrig;
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vNew->data = NULL;
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/* leave coords, s, t undefined */
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/* fix other edges on this vertex loop */
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e = eOrig;
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do {
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e->Org = vNew;
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e = e->Onext;
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} while( e != eOrig );
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}
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/* MakeFace( eOrig, fNext ) creates a new face and makes it the left face
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* of all edges in the face loop to which eOrig belongs. "fNext" gives
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* a place to insert the new face in the global face list. We insert
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* the new face *before* fNext so that algorithms which walk the face
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* list will not see the newly created faces.
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*/
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static void MakeFace( GLUhalfEdge *eOrig, GLUface *fNext )
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{
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GLUface *fNew = (GLUface *)memAlloc( sizeof( GLUface ));
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GLUhalfEdge *e;
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GLUface *fPrev;
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/* insert in circular doubly-linked list before fNext */
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fPrev = fNext->prev;
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fNew->prev = fPrev;
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fPrev->next = fNew;
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fNew->next = fNext;
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fNext->prev = fNew;
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fNew->anEdge = eOrig;
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fNew->data = NULL;
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fNew->trail = NULL;
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fNew->marked = FALSE;
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/* The new face is marked "inside" if the old one was. This is a
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* convenience for the common case where a face has been split in two.
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*/
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fNew->inside = fNext->inside;
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/* fix other edges on this face loop */
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e = eOrig;
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do {
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e->Lface = fNew;
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e = e->Lnext;
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} while( e != eOrig );
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}
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/* KillEdge( eDel ) destroys an edge (the half-edges eDel and eDel->Sym),
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* and removes from the global edge list.
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*/
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static void KillEdge( GLUhalfEdge *eDel )
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{
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GLUhalfEdge *ePrev, *eNext;
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/* Half-edges are allocated in pairs, see EdgePair above */
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if( eDel->Sym < eDel ) { eDel = eDel->Sym; }
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/* delete from circular doubly-linked list */
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eNext = eDel->next;
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ePrev = eDel->Sym->next;
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eNext->Sym->next = ePrev;
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ePrev->Sym->next = eNext;
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memFree( eDel );
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}
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/* KillVertex( vDel ) destroys a vertex and removes it from the global
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* vertex list. It updates the vertex loop to point to a given new vertex.
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*/
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static void KillVertex( GLUvertex *vDel, GLUvertex *newOrg )
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{
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GLUhalfEdge *e, *eStart = vDel->anEdge;
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GLUvertex *vPrev, *vNext;
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/* change the origin of all affected edges */
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e = eStart;
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do {
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e->Org = newOrg;
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e = e->Onext;
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} while( e != eStart );
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/* delete from circular doubly-linked list */
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vPrev = vDel->prev;
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vNext = vDel->next;
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vNext->prev = vPrev;
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vPrev->next = vNext;
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memFree( vDel );
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}
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/* KillFace( fDel ) destroys a face and removes it from the global face
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* list. It updates the face loop to point to a given new face.
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*/
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static void KillFace( GLUface *fDel, GLUface *newLface )
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{
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GLUhalfEdge *e, *eStart = fDel->anEdge;
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GLUface *fPrev, *fNext;
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/* change the left face of all affected edges */
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e = eStart;
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do {
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e->Lface = newLface;
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e = e->Lnext;
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} while( e != eStart );
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/* delete from circular doubly-linked list */
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fPrev = fDel->prev;
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fNext = fDel->next;
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fNext->prev = fPrev;
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fPrev->next = fNext;
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memFree( fDel );
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}
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/****************** Basic Edge Operations **********************/
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/* __gl_meshMakeEdge creates one edge, two vertices, and a loop (face).
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* The loop consists of the two new half-edges.
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*/
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GLUhalfEdge *__gl_meshMakeEdge( GLUmesh *mesh )
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{
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GLUhalfEdge *e = MakeEdge( &mesh->eHead );
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MakeVertex( e, &mesh->vHead );
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MakeVertex( e->Sym, &mesh->vHead );
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MakeFace( e, &mesh->fHead );
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return e;
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}
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/* __gl_meshSplice( eOrg, eDst ) is the basic operation for changing the
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* mesh connectivity and topology. It changes the mesh so that
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* eOrg->Onext <- OLD( eDst->Onext )
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* eDst->Onext <- OLD( eOrg->Onext )
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* where OLD(...) means the value before the meshSplice operation.
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*
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* This can have two effects on the vertex structure:
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* - if eOrg->Org != eDst->Org, the two vertices are merged together
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* - if eOrg->Org == eDst->Org, the origin is split into two vertices
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* In both cases, eDst->Org is changed and eOrg->Org is untouched.
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*
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* Similarly (and independently) for the face structure,
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* - if eOrg->Lface == eDst->Lface, one loop is split into two
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* - if eOrg->Lface != eDst->Lface, two distinct loops are joined into one
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* In both cases, eDst->Lface is changed and eOrg->Lface is unaffected.
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*
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* Some special cases:
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* If eDst == eOrg, the operation has no effect.
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* If eDst == eOrg->Lnext, the new face will have a single edge.
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* If eDst == eOrg->Lprev, the old face will have a single edge.
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* If eDst == eOrg->Onext, the new vertex will have a single edge.
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* If eDst == eOrg->Oprev, the old vertex will have a single edge.
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*/
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void __gl_meshSplice( GLUhalfEdge *eOrg, GLUhalfEdge *eDst )
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{
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int joiningLoops = FALSE;
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int joiningVertices = FALSE;
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if( eOrg == eDst ) return;
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if( eDst->Org != eOrg->Org ) {
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/* We are merging two disjoint vertices -- destroy eDst->Org */
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joiningVertices = TRUE;
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KillVertex( eDst->Org, eOrg->Org );
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}
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if( eDst->Lface != eOrg->Lface ) {
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/* We are connecting two disjoint loops -- destroy eDst->Lface */
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joiningLoops = TRUE;
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KillFace( eDst->Lface, eOrg->Lface );
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}
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/* Change the edge structure */
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Splice( eDst, eOrg );
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if( ! joiningVertices ) {
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/* We split one vertex into two -- the new vertex is eDst->Org.
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* Make sure the old vertex points to a valid half-edge.
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*/
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MakeVertex( eDst, eOrg->Org );
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eOrg->Org->anEdge = eOrg;
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}
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if( ! joiningLoops ) {
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/* We split one loop into two -- the new loop is eDst->Lface.
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* Make sure the old face points to a valid half-edge.
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*/
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MakeFace( eDst, eOrg->Lface );
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eOrg->Lface->anEdge = eOrg;
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}
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}
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/* __gl_meshDelete( eDel ) removes the edge eDel. There are several cases:
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* if (eDel->Lface != eDel->Rface), we join two loops into one; the loop
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* eDel->Lface is deleted. Otherwise, we are splitting one loop into two;
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* the newly created loop will contain eDel->Dst. If the deletion of eDel
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* would create isolated vertices, those are deleted as well.
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*
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* This function could be implemented as two calls to __gl_meshSplice
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* plus a few calls to memFree, but this would allocate and delete
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* unnecessary vertices and faces.
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*/
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void __gl_meshDelete( GLUhalfEdge *eDel )
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{
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GLUhalfEdge *eDelSym = eDel->Sym;
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int joiningLoops = FALSE;
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/* First step: disconnect the origin vertex eDel->Org. We make all
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* changes to get a consistent mesh in this "intermediate" state.
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*/
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if( eDel->Lface != eDel->Rface ) {
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/* We are joining two loops into one -- remove the left face */
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joiningLoops = TRUE;
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KillFace( eDel->Lface, eDel->Rface );
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}
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if( eDel->Onext == eDel ) {
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KillVertex( eDel->Org, NULL );
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} else {
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/* Make sure that eDel->Org and eDel->Rface point to valid half-edges */
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eDel->Rface->anEdge = eDel->Oprev;
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eDel->Org->anEdge = eDel->Onext;
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Splice( eDel, eDel->Oprev );
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if( ! joiningLoops ) {
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/* We are splitting one loop into two -- create a new loop for eDel. */
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MakeFace( eDel, eDel->Lface );
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}
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}
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/* Claim: the mesh is now in a consistent state, except that eDel->Org
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* may have been deleted. Now we disconnect eDel->Dst.
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*/
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if( eDelSym->Onext == eDelSym ) {
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KillVertex( eDelSym->Org, NULL );
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KillFace( eDelSym->Lface, NULL );
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} else {
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/* Make sure that eDel->Dst and eDel->Lface point to valid half-edges */
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eDel->Lface->anEdge = eDelSym->Oprev;
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eDelSym->Org->anEdge = eDelSym->Onext;
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Splice( eDelSym, eDelSym->Oprev );
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}
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/* Any isolated vertices or faces have already been freed. */
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KillEdge( eDel );
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}
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/******************** Other Edge Operations **********************/
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/* All these routines can be implemented with the basic edge
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* operations above. They are provided for convenience and efficiency.
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*/
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/* __gl_meshAddEdgeVertex( eOrg ) creates a new edge eNew such that
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* eNew == eOrg->Lnext, and eNew->Dst is a newly created vertex.
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* eOrg and eNew will have the same left face.
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*/
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GLUhalfEdge *__gl_meshAddEdgeVertex( GLUhalfEdge *eOrg )
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{
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GLUhalfEdge *eNew = MakeEdge( eOrg );
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GLUhalfEdge *eNewSym = eNew->Sym;
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/* Connect the new edge appropriately */
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Splice( eNew, eOrg->Lnext );
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/* Set the vertex and face information */
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eNew->Org = eOrg->Dst;
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MakeVertex( eNewSym, eNew->Org );
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eNew->Lface = eNewSym->Lface = eOrg->Lface;
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return eNew;
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}
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/* __gl_meshSplitEdge( eOrg ) splits eOrg into two edges eOrg and eNew,
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* such that eNew == eOrg->Lnext. The new vertex is eOrg->Dst == eNew->Org.
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* eOrg and eNew will have the same left face.
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*/
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GLUhalfEdge *__gl_meshSplitEdge( GLUhalfEdge *eOrg )
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{
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GLUhalfEdge *eNew = __gl_meshAddEdgeVertex( eOrg )->Sym;
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/* Disconnect eOrg from eOrg->Dst and connect it to eNew->Org */
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Splice( eOrg->Sym, eOrg->Sym->Oprev );
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Splice( eOrg->Sym, eNew );
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/* Set the vertex and face information */
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eOrg->Dst = eNew->Org;
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eNew->Dst->anEdge = eNew->Sym; /* may have pointed to eOrg->Sym */
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eNew->Rface = eOrg->Rface;
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eNew->winding = eOrg->winding; /* copy old winding information */
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eNew->Sym->winding = eOrg->Sym->winding;
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return eNew;
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}
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/* __gl_meshConnect( eOrg, eDst ) creates a new edge from eOrg->Dst
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* to eDst->Org, and returns the corresponding half-edge eNew.
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* If eOrg->Lface == eDst->Lface, this splits one loop into two,
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* and the newly created loop is eNew->Lface. Otherwise, two disjoint
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* loops are merged into one, and the loop eDst->Lface is destroyed.
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*
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* If (eOrg == eDst), the new face will have only two edges.
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* If (eOrg->Lnext == eDst), the old face is reduced to a single edge.
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* If (eOrg->Lnext->Lnext == eDst), the old face is reduced to two edges.
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*/
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GLUhalfEdge *__gl_meshConnect( GLUhalfEdge *eOrg, GLUhalfEdge *eDst )
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{
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GLUhalfEdge *eNew = MakeEdge( eOrg );
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GLUhalfEdge *eNewSym = eNew->Sym;
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int joiningLoops = FALSE;
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if( eDst->Lface != eOrg->Lface ) {
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/* We are connecting two disjoint loops -- destroy eDst->Lface */
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joiningLoops = TRUE;
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KillFace( eDst->Lface, eOrg->Lface );
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}
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/* Connect the new edge appropriately */
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Splice( eNew, eOrg->Lnext );
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Splice( eNewSym, eDst );
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/* Set the vertex and face information */
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eNew->Org = eOrg->Dst;
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eNewSym->Org = eDst->Org;
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eNew->Lface = eNewSym->Lface = eOrg->Lface;
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/* Make sure the old face points to a valid half-edge */
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eOrg->Lface->anEdge = eNewSym;
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if( ! joiningLoops ) {
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/* We split one loop into two -- the new loop is eNew->Lface */
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MakeFace( eNew, eOrg->Lface );
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}
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return eNew;
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}
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/******************** Other Operations **********************/
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/* __gl_meshZapFace( fZap ) destroys a face and removes it from the
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* global face list. All edges of fZap will have a NULL pointer as their
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* left face. Any edges which also have a NULL pointer as their right face
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* are deleted entirely (along with any isolated vertices this produces).
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* An entire mesh can be deleted by zapping its faces, one at a time,
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* in any order. Zapped faces cannot be used in further mesh operations!
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*/
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void __gl_meshZapFace( GLUface *fZap )
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{
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GLUhalfEdge *eStart = fZap->anEdge;
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GLUhalfEdge *e, *eNext, *eSym;
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GLUface *fPrev, *fNext;
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/* walk around face, deleting edges whose right face is also NULL */
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eNext = eStart->Lnext;
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do {
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e = eNext;
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eNext = e->Lnext;
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e->Lface = NULL;
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if( e->Rface == NULL ) {
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/* delete the edge -- see __gl_MeshDelete above */
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if( e->Onext == e ) {
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KillVertex( e->Org, NULL );
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} else {
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/* Make sure that e->Org points to a valid half-edge */
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e->Org->anEdge = e->Onext;
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Splice( e, e->Oprev );
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}
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eSym = e->Sym;
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if( eSym->Onext == eSym ) {
|
|
KillVertex( eSym->Org, NULL );
|
|
} else {
|
|
/* Make sure that eSym->Org points to a valid half-edge */
|
|
eSym->Org->anEdge = eSym->Onext;
|
|
Splice( eSym, eSym->Oprev );
|
|
}
|
|
KillEdge( e );
|
|
}
|
|
} while( e != eStart );
|
|
|
|
/* delete from circular doubly-linked list */
|
|
fPrev = fZap->prev;
|
|
fNext = fZap->next;
|
|
fNext->prev = fPrev;
|
|
fPrev->next = fNext;
|
|
|
|
memFree( fZap );
|
|
}
|
|
|
|
|
|
/* __gl_meshNewMesh() creates a new mesh with no edges, no vertices,
|
|
* and no loops (what we usually call a "face").
|
|
*/
|
|
GLUmesh *__gl_meshNewMesh( void )
|
|
{
|
|
GLUmesh *mesh = (GLUmesh *)memAlloc( sizeof( GLUmesh ));
|
|
GLUvertex *v = &mesh->vHead;
|
|
GLUface *f = &mesh->fHead;
|
|
GLUhalfEdge *e = &mesh->eHead;
|
|
GLUhalfEdge *eSym = &mesh->eHeadSym;
|
|
|
|
v->next = v->prev = v;
|
|
v->anEdge = NULL;
|
|
v->data = NULL;
|
|
|
|
f->next = f->prev = f;
|
|
f->anEdge = NULL;
|
|
f->data = NULL;
|
|
f->trail = NULL;
|
|
f->marked = FALSE;
|
|
f->inside = FALSE;
|
|
|
|
e->next = e;
|
|
e->Sym = eSym;
|
|
e->Onext = NULL;
|
|
e->Lnext = NULL;
|
|
e->Org = NULL;
|
|
e->Lface = NULL;
|
|
e->winding = 0;
|
|
e->activeRegion = NULL;
|
|
|
|
eSym->next = eSym;
|
|
eSym->Sym = e;
|
|
eSym->Onext = NULL;
|
|
eSym->Lnext = NULL;
|
|
eSym->Org = NULL;
|
|
eSym->Lface = NULL;
|
|
eSym->winding = 0;
|
|
eSym->activeRegion = NULL;
|
|
|
|
return mesh;
|
|
}
|
|
|
|
|
|
/* __gl_meshUnion( mesh1, mesh2 ) forms the union of all structures in
|
|
* both meshes, and returns the new mesh (the old meshes are destroyed).
|
|
*/
|
|
GLUmesh *__gl_meshUnion( GLUmesh *mesh1, GLUmesh *mesh2 )
|
|
{
|
|
GLUface *f1 = &mesh1->fHead;
|
|
GLUvertex *v1 = &mesh1->vHead;
|
|
GLUhalfEdge *e1 = &mesh1->eHead;
|
|
GLUface *f2 = &mesh2->fHead;
|
|
GLUvertex *v2 = &mesh2->vHead;
|
|
GLUhalfEdge *e2 = &mesh2->eHead;
|
|
|
|
/* Add the faces, vertices, and edges of mesh2 to those of mesh1 */
|
|
if( f2->next != f2 ) {
|
|
f1->prev->next = f2->next;
|
|
f2->next->prev = f1->prev;
|
|
f2->prev->next = f1;
|
|
f1->prev = f2->prev;
|
|
}
|
|
|
|
if( v2->next != v2 ) {
|
|
v1->prev->next = v2->next;
|
|
v2->next->prev = v1->prev;
|
|
v2->prev->next = v1;
|
|
v1->prev = v2->prev;
|
|
}
|
|
|
|
if( e2->next != e2 ) {
|
|
e1->Sym->next->Sym->next = e2->next;
|
|
e2->next->Sym->next = e1->Sym->next;
|
|
e2->Sym->next->Sym->next = e1;
|
|
e1->Sym->next = e2->Sym->next;
|
|
}
|
|
|
|
memFree( mesh2 );
|
|
return mesh1;
|
|
}
|
|
|
|
|
|
#ifdef DELETE_BY_ZAPPING
|
|
|
|
/* __gl_meshDeleteMesh( mesh ) will free all storage for any valid mesh.
|
|
*/
|
|
void __gl_meshDeleteMesh( GLUmesh *mesh )
|
|
{
|
|
GLUface *fHead = &mesh->fHead;
|
|
|
|
while( fHead->next != fHead ) {
|
|
__gl_meshZapFace( fHead->next );
|
|
}
|
|
assert( mesh->vHead.next == &mesh->vHead );
|
|
|
|
memFree( mesh );
|
|
}
|
|
|
|
#else
|
|
|
|
/* __gl_meshDeleteMesh( mesh ) will free all storage for any valid mesh.
|
|
*/
|
|
void __gl_meshDeleteMesh( GLUmesh *mesh )
|
|
{
|
|
GLUface *f, *fNext;
|
|
GLUvertex *v, *vNext;
|
|
GLUhalfEdge *e, *eNext;
|
|
|
|
for( f = mesh->fHead.next; f != &mesh->fHead; f = fNext ) {
|
|
fNext = f->next;
|
|
memFree( f );
|
|
}
|
|
|
|
for( v = mesh->vHead.next; v != &mesh->vHead; v = vNext ) {
|
|
vNext = v->next;
|
|
memFree( v );
|
|
}
|
|
|
|
for( e = mesh->eHead.next; e != &mesh->eHead; e = eNext ) {
|
|
/* One call frees both e and e->Sym (see EdgePair above) */
|
|
eNext = e->next;
|
|
memFree( e );
|
|
}
|
|
|
|
memFree( mesh );
|
|
}
|
|
|
|
#endif
|
|
|
|
#ifndef NDEBUG
|
|
|
|
/* __gl_meshCheckMesh( mesh ) checks a mesh for self-consistency.
|
|
*/
|
|
void __gl_meshCheckMesh( GLUmesh *mesh )
|
|
{
|
|
GLUface *fHead = &mesh->fHead;
|
|
GLUvertex *vHead = &mesh->vHead;
|
|
GLUhalfEdge *eHead = &mesh->eHead;
|
|
GLUface *f, *fPrev;
|
|
GLUvertex *v, *vPrev;
|
|
GLUhalfEdge *e, *ePrev;
|
|
|
|
fPrev = fHead;
|
|
for( fPrev = fHead ; (f = fPrev->next) != fHead; fPrev = f) {
|
|
assert( f->prev == fPrev );
|
|
e = f->anEdge;
|
|
do {
|
|
assert( e->Sym != e );
|
|
assert( e->Sym->Sym == e );
|
|
assert( e->Lnext->Onext->Sym == e );
|
|
assert( e->Onext->Sym->Lnext == e );
|
|
assert( e->Lface == f );
|
|
e = e->Lnext;
|
|
} while( e != f->anEdge );
|
|
}
|
|
assert( f->prev == fPrev && f->anEdge == NULL && f->data == NULL );
|
|
|
|
vPrev = vHead;
|
|
for( vPrev = vHead ; (v = vPrev->next) != vHead; vPrev = v) {
|
|
assert( v->prev == vPrev );
|
|
e = v->anEdge;
|
|
do {
|
|
assert( e->Sym != e );
|
|
assert( e->Sym->Sym == e );
|
|
assert( e->Lnext->Onext->Sym == e );
|
|
assert( e->Onext->Sym->Lnext == e );
|
|
assert( e->Org == v );
|
|
e = e->Onext;
|
|
} while( e != v->anEdge );
|
|
}
|
|
assert( v->prev == vPrev && v->anEdge == NULL && v->data == NULL );
|
|
|
|
ePrev = eHead;
|
|
for( ePrev = eHead ; (e = ePrev->next) != eHead; ePrev = e) {
|
|
assert( e->Sym->next == ePrev->Sym );
|
|
assert( e->Sym != e );
|
|
assert( e->Sym->Sym == e );
|
|
assert( e->Org != NULL );
|
|
assert( e->Dst != NULL );
|
|
assert( e->Lnext->Onext->Sym == e );
|
|
assert( e->Onext->Sym->Lnext == e );
|
|
}
|
|
assert( e->Sym->next == ePrev->Sym
|
|
&& e->Sym == &mesh->eHeadSym
|
|
&& e->Sym->Sym == e
|
|
&& e->Org == NULL && e->Dst == NULL
|
|
&& e->Lface == NULL && e->Rface == NULL );
|
|
}
|
|
|
|
#endif
|