Working With Edges

[davedjohnson]

Is there an easy way to find an edge loop? I have a closed polygonal surface that I delete a few polygons from. This leaves a hole. I want to fill the hole, but I'm having trouble finding the points that make up the edge/boundary.

Dave

[Slapdaddy]

I tackled the same problem recently and I found it easiest to make my own edge structure by running through all the faces in the gdp and adding edges. Any edge that did not share 2 faces had a problem. 1 face and it is part of the hole. 3 or more and you don't have well behaved mesh.

[davedjohnson]

So I know how to go through each face in the gdp, but how do I add edges? And once I do, how do I know how many faces shared it?

Dave

[sibarrick]

here's a few bits and bobs I've been using.

const GEO_Point       *pt0,*pt1;
const GEO_Primitive   *tri;
GB_PointRefArray      prefarr(gdp,0);
GB_EdgeGroup          edgeGroup(*gdp,"tmpedge");
UT_IntArray              primlist(2);


//set pt0 and pt1 here
connectedPrims.findPolysUsingEdge(*pt0, *pt1, primlist, prefarr);
   
tri=gdp->primitives()( primlist(1) )
tri->getVertexCount(); 

edgeGroup.add((GB_Element*)pt0,(GB_Element*)pt1,prim);

[davedjohnson]

here's a few bits and bobs I've been using.

const GEO_Point 

[sibarrick]

sorry

 GEO_Closure           connectedPrims(*gdp);