private void NewMethod(List <SpanningTree> ret, int tabId, Tri3 v1, Tri3 v2)
{
var t1 = ret.Single(p => p.Faces.Any(q => q.Index == v1.Index));
var common = v1.Vertices.Where(p => v2.Vertices.Any(q => q.Index == p.Index)).ToArray();
var t1p = new SpanningTree(t1.Edges.Union(new[] { new DualEdge(v1, new SterileTri3(v2, tabId, common)) }));
ret.Remove(t1);
ret.Add(t1p);
}
private static IEnumerable <BothTri> Flatten(
Mesh mesh,
SpanningTree spanTree,
Tri3 node)
{
return(FlattenWorker(
mesh,
spanTree,
node,
null,
new HashSet <int>(),
0));
}
private static IEnumerable <BothTri> FlattenWorker(
Mesh mesh,
SpanningTree spanTree,
Tri3 curr,
BothTri prev,
HashSet <int> visitedNodes,
int depth)
{
// Console.WriteLine("".PadLeft(depth, '.') + curr.Index);
if (visitedNodes.Contains(curr.Index))
{
return(new BothTri[0]);
}
visitedNodes.Add(curr.Index);
var node = curr;
Tri3 nodePrev = null;
if (prev != null)
{
// Need to treat the common edge special.
var ab = curr.CommonEdge(prev.Space);
var abi = ab.Select(p => p.Index).ToArray();
var c = curr.Vertices.Where(p => !abi.Contains(p.Index)).Single();
var origOrder = curr.Vertices.Select(p => p.Index).ToArray();
var newOrder = new int[] { ab[0].Index, ab[1].Index, c.Index };
var curr2 = new Tri3(ab[0], ab[1], c, curr.Index);
curr = new Tri3(ab[0], ab[1], c, curr.Index);
node = prev.SpaceToPaper.Apply(curr);
var c2 = prev.Space.Vertices.Where(p => !abi.Contains(p.Index)).Single();
nodePrev = new Tri3(ab[0], ab[1], c2);
nodePrev = prev.SpaceToPaper.Apply(nodePrev);
}
var tri1 = node.Translate(node.A.Neg());
var BYtoX = tri1.B.GetXYRot();
var tri2 = tri1.Apply(BYtoX);
var BZtoX = tri2.B.GetXZRot();
var tri3 = tri2.Apply(BZtoX);
var CZtoY = tri3.C.GetYZRot();
var tri4 = tri3.Apply(CZtoY);
nodePrev = nodePrev?.Translate(node.A.Neg()).Apply(BYtoX).Apply(BZtoX);
// Need to check if rotation put tri4 over prev.Paper. This is easy because the common axis is along x, and z=0.
if (prev != null)
{
// Need to determine which
if (tri4.C.Y > 0 && nodePrev.C.Y > 0)
{
// overlap. Just need to do another rotation around xhat.
CZtoY = Mat3.RotateYZ(Math.PI).Mult(CZtoY);
}
}
Mat3 spaceToPaper = CZtoY.Mult(BZtoX.Mult(BYtoX));
if (prev != null)
{
// Need to restore angle of the common edge.
spaceToPaper = BYtoX.Inv().Mult(BZtoX.Inv().Mult(spaceToPaper));
}
Transform t;
if (prev == null)
{
t = Transform.ContructRT(node.A.Neg(), spaceToPaper);
}
else
{
t = Transform.ContructTRT(node.A.Neg(), spaceToPaper);
}
if (prev != null)
{
// Apply atop previous transform
t = t.Compose(prev.SpaceToPaper);
}
var test1 = t.Apply(curr);
if (Math.Abs(test1.C.Z) > 1e-8)
{
throw new InvalidOperationException();
}
var test4 = curr;
BothTri bt = new BothTri(curr, t);
var test0 = bt.Paper;
var test2 = bt.SpaceToPaper.Apply(curr);
var test3 = bt.PaperToSpace(bt.Paper);
var test5 = bt.Space;
if (test0.Dist(test1) > 1e-5)
{
throw new InvalidOperationException();
}
if (test0.Dist(test2) > 1e-5)
{
throw new InvalidOperationException();
}
if (test3.Dist(test4) > 1e-5)
{
throw new InvalidOperationException();
}
if (test3.Dist(test5) > 1e-5)
{
throw new InvalidOperationException();
}
var ret = new List <BothTri>()
{
bt
};
foreach (Tri3 child in spanTree.GetConnectedNodes(curr))
{
var cbt = FlattenWorker(mesh, spanTree, child, bt, visitedNodes, depth + 1);
ret.AddRange(cbt);
}
return(ret);
}
public static IEnumerable <IEnumerable <BothTri> > unfold(SpanningTree spanningTree, IEnumerable <BothTri> faces)
{
var epsilon = 1E-12; // accuracy
var faceIntersections = new List <Tuple <int, int> >();
foreach (var face1 in faces)
{
foreach (var face2 in faces.Where(p => p.Index < face1.Index))
{
if (face1.Paper.TriangleIntersection(face2.Paper, epsilon))
{
faceIntersections.Add(new Tuple <int, int>(face1.Index, face2.Index));
}
}
}
// Find all paths between intersecting triangles
var edgepaths = new List <IEnumerable <DualEdge> >();
foreach (var intersection in faceIntersections)
{
edgepaths.Add(spanningTree.Path(intersection.Item1, intersection.Item2));
}
// Count the number of times each edge occurs
var allEdgesInPaths = edgepaths
.SelectMany(p => p)
.Select(p => p.Index)
.Distinct()
.Select(p => new
{
EdgeId = p,
NumPaths = edgepaths.Where(q => q.Any(r => r.Index == p)).Count(),
})
.ToArray();
// set of new cut edges
var cuts = new List <int>();
//set of already covered paths
var C = new List <IEnumerable <DualEdge> >();
while (C.Count != edgepaths.Count)
{
// Determine the edge with minimum average cost at which it covers new elements.
var cutWeights = new double[allEdgesInPaths.Length];
for (int i = 0; i < allEdgesInPaths.Length; i++)
{
// Count how many of the paths where the
// edge occurs have already been cut
var numInC = C
.Where(p => p
.Select(q => q.Index)
.Contains(allEdgesInPaths[i].EdgeId))
.Count();
// Determine the weight
cutWeights[i] = ((allEdgesInPaths[i].NumPaths - numInC) > 0) ?
1.0 / (allEdgesInPaths[i].NumPaths - numInC) :
double.MaxValue;
}
// Find the edge with the lowest weight
var minimalIndex = cutWeights
.Select((p, i) => new { p, i })
.OrderBy(p => p.p)
.First().i; // np.argmin(cutWeights)
cuts.Add(allEdgesInPaths[minimalIndex].EdgeId);
// Find all paths where the edge occurs and add them to C.
foreach (IEnumerable <DualEdge> path in edgepaths)
{
if (path
.Select(p => p.Index)
.Contains(allEdgesInPaths[minimalIndex].EdgeId) &&
!C.Contains(path))
{
C.Add(path);
}
}
}
// Make the cuts in the spanning tree
IEnumerable <SpanningTree> connectedComponents = spanningTree.MakeCuts(cuts);
BothTri[][] splitFaces = connectedComponents
.Select(p => p.Faces
.Select(q =>
{
if (q is SterileTri3 st)
{
return(new BothTri(faces.Single(r => r.Index == -q.Index), st.TabId, st.Common));
}
else
{
return(faces.Single(r => r.Index == q.Index));
}
})
.ToArray())
.Select(p => p)
.ToArray();
return(splitFaces);
}