ibgoedge.cxx

Delaunay三角形的网格剖分程序

#include "ibgoctree.hxx"
#include "cogwarnings.hxx"

void ibgOctree::findEdges()
{
  //  return;
  wzIndex edge=edges.create();
  wzIndex rc,s,i,f,p;
  wzRangeLoop(faces,f){
    wzIndex l=fLine[f];
    for(s=0;s<LineSides;s++){
      p = getPlane(l,s);
      if(!p){
	// that's possible - no plane in a direction which intersects a cube;
	continue;
      }
      // now, we have to identify the face as on one of the four sides of the plane.
      // note that one of the end points of the line may be a middle point.
      ibgIndex bnu=lNodeDown[l];	// doubles some getPlane-code
      ibgIndex bno=lNodeUp[l];
      ibgIndex d  = lDirection(l);
      ibgIndex piu = lsPlane[d][s], pio = lsPlane[down(d)][s];
      wzAssert(p==bnPlane[piu][bnu]); wzAssert(p==bnPlane[pio][bno]);
      ibgIndex buu=pNode[pReverse[piu]][p];
      ibgIndex boo=pNode[pReverse[pio]][p];
      wzAssert((buu==bnu) || (boo==bno));
      piu = lsPlane[d][sOther[s]], pio = lsPlane[down(d)][sOther[s]];
      ibgIndex bru=pNode[pReverse[piu]][p];
      ibgIndex bro=pNode[pReverse[pio]][p];
      wzAssert(bru != buu);
      wzAssert(bru != bro);
      wzAssert(bru != boo);
      wzAssert(bro != buu);
      wzAssert(bro != boo);
      wzAssert(buu != boo);
      // now it seems clear that we have found the 4 nodes correctly.
      // time to search for the edge intersection with the plane.
      try{
	cogFlag1 f1(fPoint[f],fPointDown[f],fPointUp[f]);
	cogFlag2 f2(ePoint[edge],ePointFace[edge],ePointDown[edge],ePointUp[edge]);
	rc=geo->Square(f2,f1,
		       cogSquare(nPoint[bnBase[buu]],
				 nPoint[bnBase[boo]],
				 nPoint[bnBase[bro]],
				 nPoint[bnBase[bru]]));
	if(rc!=cogRCEdgeFound){
	  // establishing connection to the other face omitted yet;
	  // means, no pair establishment yet.
	  continue;
	}
	for(i=0;i<PlaneSides;i++){
	  eVertex[i][edge] = 0;
	  if(!pEdge[p]) noteEdgeOnCube(p,edge,i);
	}
	eFace[edge] = f; fEdge[s][f]=edge;
	ePlane[edge]= p; eNext[edge] = pEdge[p]; pEdge[p] = edge;
	eIdent[edge]= 0;	// means, not yet implemented;
	edge = edges.create();
      }catch(...){
	cogInfoEdgeProblems();
      }
    }
  }
  edges.destroy(edge);
}