private static void InsertEdge(TriMesh mesh, TriMesh.HalfEdge inner, TriMesh.HalfEdge outer)
{
//TriMesh.Edge left = new TriMesh.Edge();
//left.HalfEdge0 = outer;
//outer.Edge = left;
//inner.Next.Edge = left;
//TriMesh.Edge right = outer.Edge;
//right.HalfEdge0 = inner;
//inner.Edge = right;
//outer.Opposite.Edge = right;
//inner.Opposite = outer.Opposite;
//inner.Next.Opposite = outer;
//outer.Opposite.Opposite = inner;
//outer.Opposite = inner.Next;
inner.Opposite = outer.Opposite;
inner.Next.Opposite = outer;
outer.Opposite.Opposite = inner;
outer.Opposite = inner.Next;
outer.Edge.HalfEdge0 = outer;
TriMesh.Edge edge = new TriMesh.Edge();
edge.HalfEdge0 = inner;
inner.Edge = edge;
inner.Opposite.Edge = edge;
inner.Next.Edge = outer.Edge;
mesh.AppendToEdgeList(edge);
}
TriMesh.Edge CreateNewEdge(TriMesh.Vertex from, TriMesh.Vertex to)
{
TriMesh mesh = (TriMesh)from.Mesh;
// Create new edge
TriMesh.Edge edge = new TriMesh.Edge();
mesh.AppendToEdgeList(edge);
// Create new halfedges
TriMesh.HalfEdge hf0 = new TriMesh.HalfEdge();
mesh.AppendToHalfedgeList(hf0);
hf0.Opposite = new TriMesh.HalfEdge();
mesh.AppendToHalfedgeList(hf0.Opposite);
// Connect opposite halfedge to inner halfedge
hf0.Opposite.Opposite = hf0;
// Connect edge to halfedges
edge.HalfEdge0 = hf0;
// Connect halfedges to edge
hf0.Edge = edge;
hf0.Opposite.Edge = edge;
// Connect halfedges to vertices
hf0.ToVertex = to;
hf0.Opposite.ToVertex = from;
// Connect vertex to outgoing halfedge if it doesn't have one yet
if (from.HalfEdge == null)
{
from.HalfEdge = hf0;
}
return(edge);
}
public static TriMesh.Vertex VertexSplit(TriMesh.Vertex v1, TriMesh.Vertex share1,
TriMesh.Vertex share2, Vector3D v1Position, Vector3D v2Position, int fixedIndex)
{
TriMesh.HalfEdge[] hfs = FindGroup(v1, share1, share2);
TriMesh mesh = (TriMesh)v1.Mesh;
v1.Traits.Position = v1Position;
v1.HalfEdge = hfs[0];
TriMesh.Vertex v2 = new TriMesh.Vertex();
v2.Traits = new VertexTraits(v2Position);
v2.Traits.FixedIndex = fixedIndex;
v2.HalfEdge = hfs[1];
mesh.AppendToVertexList(v2);
for (int i = 0; i < hfs.Length - 1; i++)
{
hfs[i].Opposite.ToVertex = v2;
}
TriMesh.HalfEdge[] triangle1 = AddInnerTriangle(mesh, v1, v2, share1);
InsertEdge(mesh, triangle1[1], hfs[0]);
TriMesh.HalfEdge[] triangle2 = AddInnerTriangle(mesh, v2, v1, share2);
InsertEdge(mesh, triangle2[1], hfs[hfs.Length - 1]);
TriMesh.Edge edge = new TriMesh.Edge();
edge.HalfEdge0 = triangle1[0];
triangle1[0].Edge = edge;
triangle2[0].Edge = edge;
triangle1[0].Opposite = triangle2[0];
triangle2[0].Opposite = triangle1[0];
mesh.AppendToEdgeList(edge);
return(v2);
}
/// <summary>
/// Adds a face to the mesh with the specified face traits.
/// </summary>
/// <param name="faceTraits">The custom traits for the face to add to the mesh.</param>
/// <param name="faceVertices">The vertices of the face in counterclockwise order.</param>
/// <returns>The face created by this method.</returns>
/// <exception cref="BadTopologyException">
/// Thrown when fewer than three vertices are given or the vertices cannot form a valid face.
/// </exception>
/// <exception cref="ArgumentNullException">Thrown when a null vertex is given.</exception>
private static TriMesh.Face CreateFace(TriMesh mesh, params TriMesh.Vertex[] faceVertices)
{
int n = faceVertices.Length;
// Require at least 3 vertices
if (n < 3)
{
throw new BadTopologyException("Cannot create a polygon with fewer than three vertices.");
}
TriMesh.Edge e;
TriMesh.Face f;
TriMesh.HalfEdge[] faceHalfedges = new TriMesh.HalfEdge[n];
bool[] isNewEdge = new bool[n], isUsedVertex = new bool[n];
for (int i = 0; i < n; i++)
{
int j = (i + 1) % n;
faceHalfedges[i] = faceVertices[i].FindHalfedgeTo(faceVertices[j]);
}
// Make sure input is (mostly) acceptable before making any changes to the mesh
for (int i = 0; i < n; ++i)
{
int j = (i + 1) % n;
if (faceVertices[i] == null)
{
throw new ArgumentNullException("Can't add a null vertex to a face.");
}
if (!faceVertices[i].OnBoundary)
{
throw new BadTopologyException("Can't add an edge to a vertex on the interior of a mesh.");
}
// Find existing halfedges for this face
faceHalfedges[i] = faceVertices[i].FindHalfedgeTo(faceVertices[j]);
isNewEdge[i] = (faceHalfedges[i] == null);
isUsedVertex[i] = (faceVertices[i].HalfEdge != null);
if (!isNewEdge[i] && !faceHalfedges[i].OnBoundary)
{
throw new BadTopologyException("Can't add more than two faces to an edge.");
}
}
// Create face
f = new TriMesh.Face(default(FaceTraits));
mesh.AppendToFaceList(f);
// Create new edges
for (int i = 0; i < n; ++i)
{
int j = (i + 1) % n;
if (isNewEdge[i])
{
// Create new edge
e = new TriMesh.Edge();
mesh.AppendToEdgeList(e);
// Create new halfedges
faceHalfedges[i] = new TriMesh.HalfEdge();
mesh.AppendToHalfedgeList(faceHalfedges[i]);
faceHalfedges[i].Opposite = new TriMesh.HalfEdge();
mesh.AppendToHalfedgeList(faceHalfedges[i].Opposite);
// Connect opposite halfedge to inner halfedge
faceHalfedges[i].Opposite.Opposite = faceHalfedges[i];
// Connect edge to halfedges
e.HalfEdge0 = faceHalfedges[i];
// Connect halfedges to edge
faceHalfedges[i].Edge = e;
faceHalfedges[i].Opposite.Edge = e;
// Connect halfedges to vertices
faceHalfedges[i].ToVertex = faceVertices[j];
faceHalfedges[i].Opposite.ToVertex = faceVertices[i];
// Connect vertex to outgoing halfedge if it doesn't have one yet
if (faceVertices[i].HalfEdge == null)
{
faceVertices[i].HalfEdge = faceHalfedges[i];
}
}
if (faceHalfedges[i].Face != null)
{
throw new BadTopologyException("An inner halfedge already has a face assigned to it.");
}
// Connect inner halfedge to face
faceHalfedges[i].Face = f;
}
// Connect next/previous halfedges
for (int i = 0; i < n; ++i)
{
int j = (i + 1) % n;
// Outer halfedges
if (isNewEdge[i] && isNewEdge[j] && isUsedVertex[j]) // Both edges are new and vertex has faces connected already
{
TriMesh.HalfEdge closeHalfedge = null;
// Find the closing halfedge of the first available opening
foreach (TriMesh.HalfEdge h in faceVertices[j].HalfEdges)
{
if (h.Face == null)
{
closeHalfedge = h;
break;
}
}
TriMesh.HalfEdge openHalfedge = closeHalfedge.Previous;
// Link new outer halfedges into this opening
faceHalfedges[i].Opposite.Previous = openHalfedge;
openHalfedge.Next = faceHalfedges[i].Opposite;
faceHalfedges[j].Opposite.Next = closeHalfedge;
closeHalfedge.Previous = faceHalfedges[j].Opposite;
}
else if (isNewEdge[i] && isNewEdge[j]) // Both edges are new
{
faceHalfedges[i].Opposite.Previous = faceHalfedges[j].Opposite;
faceHalfedges[j].Opposite.Next = faceHalfedges[i].Opposite;
}
else if (isNewEdge[i] && !isNewEdge[j]) // This is new, next is old
{
faceHalfedges[i].Opposite.Previous = faceHalfedges[j].Previous;
faceHalfedges[j].Previous.Next = faceHalfedges[i].Opposite;
}
else if (!isNewEdge[i] && isNewEdge[j]) // This is old, next is new
{
faceHalfedges[i].Next.Previous = faceHalfedges[j].Opposite;
faceHalfedges[j].Opposite.Next = faceHalfedges[i].Next;
}
// Relink faces before adding new edges if they are in the way of a new face
else if (!isNewEdge[i] && !isNewEdge[j] && faceHalfedges[i].Next != faceHalfedges[j])
{
TriMesh.HalfEdge closeHalfedge = faceHalfedges[i].Opposite;
// Find the closing halfedge of the opening opposite the opening halfedge i is on
do
{
closeHalfedge = closeHalfedge.Previous.Opposite;
} while (closeHalfedge.Face != null && closeHalfedge != faceHalfedges[j] &&
closeHalfedge != faceHalfedges[i].Opposite);
if (closeHalfedge == faceHalfedges[j] || closeHalfedge == faceHalfedges[i].Opposite)
{
throw new BadTopologyException("Unable to find an opening to relink an existing face.");
}
TriMesh.HalfEdge openHalfedge = closeHalfedge.Previous;
// Remove group of faces between two openings, close up gap to form one opening
openHalfedge.Next = faceHalfedges[i].Next;
faceHalfedges[i].Next.Previous = openHalfedge;
// Insert group of faces into target opening
faceHalfedges[j].Previous.Next = closeHalfedge;
closeHalfedge.Previous = faceHalfedges[j].Previous;
}
// Inner halfedges
faceHalfedges[i].Next = faceHalfedges[j];
faceHalfedges[j].Previous = faceHalfedges[i];
}
// Connect face to an inner halfedge
f.HalfEdge = faceHalfedges[0];
return(f);
}
public TriMesh.Vertex VertexSplit1(TriMesh.Vertex v, TriMesh.Vertex vshard1, TriMesh.Vertex vshard2, Vector3D v1Position, Vector3D v2Position, int v2FixedIndex)
{
//1.Get two group of verties
TriMesh.HalfEdge[] processGroup = FindGroup(v, vshard1, vshard2);
TriMesh mesh = (TriMesh)v.Mesh;
TriMesh.Vertex v1 = null;
TriMesh.Vertex v2 = null;
TriMesh.Vertex newVertex = null;
v1 = v;
v.Traits.Position = v1Position;
v2 = new TriMesh.Vertex();
v2.Traits = new VertexTraits(Vector3D.Zero);
newVertex = v2;
newVertex.Traits.FixedIndex = v2FixedIndex;
v2.Mesh = v.Mesh;
v2.Traits.Position = v2Position;
//2.Process the Topology
TriMesh.HalfEdge hf1Origin = processGroup[0];
TriMesh.HalfEdge hf2Origin = processGroup[processGroup.Length - 1];
//Add new edge
TriMesh.HalfEdge hf3 = new TriMesh.HalfEdge();
TriMesh.HalfEdge hf3Oppsite = new TriMesh.HalfEdge();
TriMesh.Edge edge = new TriMesh.Edge();
hf3.Opposite = hf3Oppsite;
hf3Oppsite.Opposite = hf3;
edge.HalfEdge0 = hf3;
edge.HalfEdge1 = hf3Oppsite;
hf3.Edge = edge;
hf3Oppsite.Edge = edge;
hf3.ToVertex = v2;
hf3Oppsite.ToVertex = v1;
//Handle hf1Origin which is outter hafledge [INNER]
TriMesh.HalfEdge hf1 = new TriMesh.HalfEdge();
hf1.Opposite = hf1Origin;
hf1.ToVertex = v1;
TriMesh.HalfEdge hf1Other = new TriMesh.HalfEdge();
hf1Other.Opposite = hf1Origin.Opposite;
hf1Other.ToVertex = hf1Origin.ToVertex;
hf1.Previous = hf1Other;
hf1Other.Next = hf1;
hf1.Next = hf3;
hf3.Previous = hf1;
hf1Other.Previous = hf3;
hf3.Next = hf1Other;
//Handle hf2Origin which is inner hafledge [INNER]
TriMesh.HalfEdge hf2 = new TriMesh.HalfEdge();
hf2.Opposite = hf2Origin;
hf2.ToVertex = v2;
TriMesh.HalfEdge hf2Other = new TriMesh.HalfEdge();
hf2Other.Opposite = hf2Origin.Opposite;
hf2Other.ToVertex = hf2Origin.ToVertex;
hf2.Previous = hf2Other;
hf2Other.Next = hf2;
hf2.Next = hf3Oppsite;
hf3Oppsite.Previous = hf2;
hf2Other.Previous = hf3Oppsite;
hf3Oppsite.Next = hf2Other;
TriMesh.Face face1 = new TriMesh.Face();
TriMesh.Face face2 = new TriMesh.Face();
face1.HalfEdge = hf3;
hf3.Face = face1;
hf1.Face = face1;
hf1Other.Face = face1;
face2.HalfEdge = hf3Oppsite;
hf3Oppsite.Face = face2;
hf2.Face = face2;
hf2Other.Face = face2;
//Process the outside
TriMesh.Edge edge1 = new TriMesh.Edge();
TriMesh.HalfEdge hf1OriginOppsite = hf1Origin.Opposite;
hf1Origin.Opposite = hf1;
hf1.Edge = hf1Origin.Edge;
hf1OriginOppsite.Opposite = hf1Other;
hf1OriginOppsite.ToVertex = v2;
hf1OriginOppsite.Edge = edge1;
hf1Other.Edge = edge1;
edge1.HalfEdge0 = hf1Other;
edge1.HalfEdge1 = hf1OriginOppsite;
TriMesh.Edge edge2 = new TriMesh.Edge();
TriMesh.HalfEdge hf2OriginOppsite = hf2Origin.Opposite;
hf2Origin.Opposite = hf2;
hf2.Edge = hf2Origin.Edge;
hf2OriginOppsite.Opposite = hf2Other;
hf2OriginOppsite.ToVertex = v1;
hf2OriginOppsite.Edge = edge2;
hf2Other.Edge = edge2;
edge2.HalfEdge0 = hf2Other;
edge2.HalfEdge1 = hf2OriginOppsite;
v1.HalfEdge = hf1Origin;
v2.HalfEdge = hf2Origin;
mesh.AppendToEdgeList(edge);
mesh.AppendToEdgeList(edge1);
mesh.AppendToEdgeList(edge2);
mesh.AppendToFaceList(face1);
mesh.AppendToFaceList(face2);
mesh.AppendToHalfedgeList(hf1);
mesh.AppendToHalfedgeList(hf1Other);
mesh.AppendToHalfedgeList(hf2);
mesh.AppendToHalfedgeList(hf2Other);
mesh.AppendToHalfedgeList(hf3);
mesh.AppendToHalfedgeList(hf3Oppsite);
mesh.AppendToVertexList(newVertex);
for (int i = 1; i < processGroup.Length - 1; i++)
{
processGroup[i].Opposite.ToVertex = newVertex;
}
//mesh.FixIndex();
return(newVertex);
}
private static void InsertEdge(TriMesh mesh, TriMesh.HalfEdge inner, TriMesh.HalfEdge outer)
{
//TriMesh.Edge left = new TriMesh.Edge();
//left.HalfEdge0 = outer;
//outer.Edge = left;
//inner.Next.Edge = left;
//TriMesh.Edge right = outer.Edge;
//right.HalfEdge0 = inner;
//inner.Edge = right;
//outer.Opposite.Edge = right;
//inner.Opposite = outer.Opposite;
//inner.Next.Opposite = outer;
//outer.Opposite.Opposite = inner;
//outer.Opposite = inner.Next;
inner.Opposite = outer.Opposite;
inner.Next.Opposite = outer;
outer.Opposite.Opposite = inner;
outer.Opposite = inner.Next;
outer.Edge.HalfEdge0 = outer;
TriMesh.Edge edge = new TriMesh.Edge();
edge.HalfEdge0 = inner;
inner.Edge = edge;
inner.Opposite.Edge = edge;
inner.Next.Edge = outer.Edge;
mesh.AppendToEdgeList(edge);
}
/// <summary>
/// Adds a face to the mesh with the specified face traits.
/// </summary>
/// <param name="faceTraits">The custom traits for the face to add to the mesh.</param>
/// <param name="faceVertices">The vertices of the face in counterclockwise order.</param>
/// <returns>The face created by this method.</returns>
/// <exception cref="BadTopologyException">
/// Thrown when fewer than three vertices are given or the vertices cannot form a valid face.
/// </exception>
/// <exception cref="ArgumentNullException">Thrown when a null vertex is given.</exception>
private static TriMesh.Face CreateFace(TriMesh mesh, params TriMesh.Vertex[] faceVertices)
{
int n = faceVertices.Length;
// Require at least 3 vertices
if (n < 3)
{
throw new BadTopologyException("Cannot create a polygon with fewer than three vertices.");
}
TriMesh.Edge e;
TriMesh.Face f;
TriMesh.HalfEdge[] faceHalfedges = new TriMesh.HalfEdge[n];
bool[] isNewEdge = new bool[n], isUsedVertex = new bool[n];
for (int i = 0; i < n; i++)
{
int j = (i + 1) % n;
faceHalfedges[i] = faceVertices[i].FindHalfedgeTo(faceVertices[j]);
}
// Make sure input is (mostly) acceptable before making any changes to the mesh
for (int i = 0; i < n; ++i)
{
int j = (i + 1) % n;
if (faceVertices[i] == null)
{
throw new ArgumentNullException("Can't add a null vertex to a face.");
}
if (!faceVertices[i].OnBoundary)
{
throw new BadTopologyException("Can't add an edge to a vertex on the interior of a mesh.");
}
// Find existing halfedges for this face
faceHalfedges[i] = faceVertices[i].FindHalfedgeTo(faceVertices[j]);
isNewEdge[i] = (faceHalfedges[i] == null);
isUsedVertex[i] = (faceVertices[i].HalfEdge != null);
if (!isNewEdge[i] && !faceHalfedges[i].OnBoundary)
{
throw new BadTopologyException("Can't add more than two faces to an edge.");
}
}
// Create face
f = new TriMesh.Face(default(FaceTraits));
mesh.AppendToFaceList(f);
// Create new edges
for (int i = 0; i < n; ++i)
{
int j = (i + 1) % n;
if (isNewEdge[i])
{
// Create new edge
e = new TriMesh.Edge();
mesh.AppendToEdgeList(e);
// Create new halfedges
faceHalfedges[i] = new TriMesh.HalfEdge();
mesh.AppendToHalfedgeList(faceHalfedges[i]);
faceHalfedges[i].Opposite = new TriMesh.HalfEdge();
mesh.AppendToHalfedgeList(faceHalfedges[i].Opposite);
// Connect opposite halfedge to inner halfedge
faceHalfedges[i].Opposite.Opposite = faceHalfedges[i];
// Connect edge to halfedges
e.HalfEdge0 = faceHalfedges[i];
// Connect halfedges to edge
faceHalfedges[i].Edge = e;
faceHalfedges[i].Opposite.Edge = e;
// Connect halfedges to vertices
faceHalfedges[i].ToVertex = faceVertices[j];
faceHalfedges[i].Opposite.ToVertex = faceVertices[i];
// Connect vertex to outgoing halfedge if it doesn't have one yet
if (faceVertices[i].HalfEdge == null)
{
faceVertices[i].HalfEdge = faceHalfedges[i];
}
}
if (faceHalfedges[i].Face != null)
{
throw new BadTopologyException("An inner halfedge already has a face assigned to it.");
}
// Connect inner halfedge to face
faceHalfedges[i].Face = f;
}
// Connect next/previous halfedges
for (int i = 0; i < n; ++i)
{
int j = (i + 1) % n;
// Outer halfedges
if (isNewEdge[i] && isNewEdge[j] && isUsedVertex[j]) // Both edges are new and vertex has faces connected already
{
TriMesh.HalfEdge closeHalfedge = null;
// Find the closing halfedge of the first available opening
foreach (TriMesh.HalfEdge h in faceVertices[j].HalfEdges)
{
if (h.Face == null)
{
closeHalfedge = h;
break;
}
}
TriMesh.HalfEdge openHalfedge = closeHalfedge.Previous;
// Link new outer halfedges into this opening
faceHalfedges[i].Opposite.Previous = openHalfedge;
openHalfedge.Next = faceHalfedges[i].Opposite;
faceHalfedges[j].Opposite.Next = closeHalfedge;
closeHalfedge.Previous = faceHalfedges[j].Opposite;
}
else if (isNewEdge[i] && isNewEdge[j]) // Both edges are new
{
faceHalfedges[i].Opposite.Previous = faceHalfedges[j].Opposite;
faceHalfedges[j].Opposite.Next = faceHalfedges[i].Opposite;
}
else if (isNewEdge[i] && !isNewEdge[j]) // This is new, next is old
{
faceHalfedges[i].Opposite.Previous = faceHalfedges[j].Previous;
faceHalfedges[j].Previous.Next = faceHalfedges[i].Opposite;
}
else if (!isNewEdge[i] && isNewEdge[j]) // This is old, next is new
{
faceHalfedges[i].Next.Previous = faceHalfedges[j].Opposite;
faceHalfedges[j].Opposite.Next = faceHalfedges[i].Next;
}
// Relink faces before adding new edges if they are in the way of a new face
else if (!isNewEdge[i] && !isNewEdge[j] && faceHalfedges[i].Next != faceHalfedges[j])
{
TriMesh.HalfEdge closeHalfedge = faceHalfedges[i].Opposite;
// Find the closing halfedge of the opening opposite the opening halfedge i is on
do
{
closeHalfedge = closeHalfedge.Previous.Opposite;
} while (closeHalfedge.Face != null && closeHalfedge != faceHalfedges[j]
&& closeHalfedge != faceHalfedges[i].Opposite);
if (closeHalfedge == faceHalfedges[j] || closeHalfedge == faceHalfedges[i].Opposite)
{
throw new BadTopologyException("Unable to find an opening to relink an existing face.");
}
TriMesh.HalfEdge openHalfedge = closeHalfedge.Previous;
// Remove group of faces between two openings, close up gap to form one opening
openHalfedge.Next = faceHalfedges[i].Next;
faceHalfedges[i].Next.Previous = openHalfedge;
// Insert group of faces into target opening
faceHalfedges[j].Previous.Next = closeHalfedge;
closeHalfedge.Previous = faceHalfedges[j].Previous;
}
// Inner halfedges
faceHalfedges[i].Next = faceHalfedges[j];
faceHalfedges[j].Previous = faceHalfedges[i];
}
// Connect face to an inner halfedge
f.HalfEdge = faceHalfedges[0];
return f;
}
