/// <summary>
/// For testing only now.
/// </summary>
/// <param name="existingEdge"></param>
/// <param name="fromVert"></param>
/// <param name="toVert"></param>
/// <returns></returns>
private HandleHalfEdge ReuseExistingConnection(HandleEdge existingEdge, HandleVertex fromVert, HandleVertex toVert)
{
// Check half-edge 1 and 2 if one points to the actual face. This is the one we use for our face then. If no one we build a new connection.
HEdgePtrCont hedge1 = _LhedgePtrCont[_LedgePtrCont[existingEdge]._he1];
HEdgePtrCont hedge2 = _LhedgePtrCont[_LedgePtrCont[existingEdge]._he2];
HandleHalfEdge hedgeToUse = new HandleHalfEdge(-1);
if (hedge2._f == -1)
{
// It is hedge 2 that is free. We should use it.
hedgeToUse = _LedgePtrCont[existingEdge]._he2;
}
else if (hedge1._f == -1)
{
// It is hedge 1 that is free. We should use it. Should never happen. TODO: Exception throw?
hedgeToUse = _LedgePtrCont[existingEdge]._he1;
}
else
{
// Neither one of the faces of the existing half-edges was free so we build a new edge.
return CreateAllNewConnection(fromVert, toVert);
}
// Updating the face pointer.
HEdgePtrCont hedge = _LhedgePtrCont[hedgeToUse];
hedge._f = new HandleFace(_LfacePtrCont.Count - 1);
_LhedgePtrCont[hedgeToUse] = new HEdgePtrCont()
{
_f = hedge._f,
_he = hedge._he,
_nhe = hedge._nhe,
_v = hedge._v,
_vn = hedge._vn,
_vuv = hedge._vuv
};
return hedgeToUse;
}
/// <summary>
/// For testing now only.
/// </summary>
/// <returns></returns>
private HandleHalfEdge CreateAllNewConnection(HandleVertex fromVert, HandleVertex toVert)
{
HEdgePtrCont hedge1 = new HEdgePtrCont()
{
_f = new HandleFace(_LfacePtrCont.Count - 1),
_he = new HandleHalfEdge(_LedgePtrCont.Count == 0 ? 1 : _LhedgePtrCont.Count + 1),
_v = new HandleVertex(toVert),
_vn = new HandleVertexNormal(-1),
_vuv = new HandleVertexUV(-1),
_nhe = new HandleHalfEdge(-1)
};
HEdgePtrCont hedge2 = new HEdgePtrCont()
{
_f = new HandleFace(-1),
_he = new HandleHalfEdge(_LedgePtrCont.Count == 0 ? 0 : _LhedgePtrCont.Count),
_v = new HandleVertex(fromVert),
_vn = new HandleVertexNormal(-1),
_vuv = new HandleVertexUV(-1),
_nhe = new HandleHalfEdge(-1)
};
_LhedgePtrCont.Add(hedge1);
_LhedgePtrCont.Add(hedge2);
_LedgePtrCont.Add(
new EdgePtrCont()
{
_he1 = new HandleHalfEdge(_LhedgePtrCont.Count - 2),
_he2 = new HandleHalfEdge(_LhedgePtrCont.Count - 1)
}
);
_LedgeHndl.Add(
new HandleEdge() { _DataIndex = _LedgePtrCont.Count - 1 }
);
// Update the vertices.
VertexPtrCont vertFrom = _LvertexPtrCont[fromVert._DataIndex];
VertexPtrCont vertTo = _LvertexPtrCont[toVert._DataIndex];
if (!vertFrom._h.isValid)
{
vertFrom._h = _LedgePtrCont[_LedgePtrCont.Count - 1]._he1;
_LvertexPtrCont[fromVert] = new VertexPtrCont() { _h = vertFrom._h };
}
if (!vertTo._h.isValid)
{
vertTo._h = _LedgePtrCont[_LedgePtrCont.Count - 1]._he2;
_LvertexPtrCont[toVert] = new VertexPtrCont() { _h = vertTo._h };
}
return _LedgePtrCont.Last()._he1;
}
/// <summary>
/// Only for testing now.
/// </summary>
/// <param name="fromVert"></param>
/// <param name="toVert"></param>
/// <returns></returns>
private HandleEdge DoesConnectionExist(HandleVertex fromVert, HandleVertex toVert)
{
return new HandleEdge(
_LedgePtrCont.FindIndex(
edgePtrCont => _LhedgePtrCont[edgePtrCont._he1]._v == fromVert && _LhedgePtrCont[edgePtrCont._he2]._v == toVert || _LhedgePtrCont[edgePtrCont._he1]._v._DataIndex == toVert && _LhedgePtrCont[edgePtrCont._he2]._v == fromVert)
);
}
/// <summary>
/// Iterator.
/// Circulate around a given vertex and enumerate all incoming halfedges.
/// </summary>
/// <param name="vertexHandle">A handle to a vertex to use as a 'center' vertex.</param>
/// <returns>An Enumerable of HalfEdge handles to be used in loops, etc.</returns>
public IEnumerable<HandleHalfEdge> EnVertexIncomingHalfEdge(HandleVertex vertexHandle)
{
List<HandleHalfEdge> LTmpIncomingHedges = new List<HandleHalfEdge>();
//Get the one outgoing half-edge for the vertex.
HandleHalfEdge currentHedge = _LvertexPtrCont[vertexHandle]._h;
//Remember the index of the first half-edge
int startHedgeIndex = currentHedge;
do
{
if (currentHedge == -1)
break;
HEdgePtrCont currentHedgeContainer = _LhedgePtrCont[currentHedge];
if (vertexHandle == _LhedgePtrCont[currentHedgeContainer._he]._v)
{
LTmpIncomingHedges.Add(currentHedgeContainer._he);
}
currentHedge = _LhedgePtrCont[currentHedgeContainer._he]._nhe;
} while (currentHedge != startHedgeIndex);
return LTmpIncomingHedges.AsEnumerable();
//return _LhedgePtrCont.Where(e => e._v == vertexHandle).AsParallel().Select(e => _LhedgePtrCont[e._he._DataIndex]._he).AsParallel().ToList();
//return (from e in _LhedgePtrCont where e._v == vertexHandle select _LhedgePtrCont[e._he]._he).AsParallel().ToList();
}
/// <summary>
/// Iterator.
/// Circulate around a given vertex and enumerate all outgoing halfedges.
/// </summary>
/// <param name="vertexHandle">A handle to a vertex to use as a 'center' vertex.</param>
/// <returns>An Enumerable of HalfEdge handles to be used in loops, etc.</returns>
public IEnumerable<HandleHalfEdge> EnVertexOutgoingHalfEdge(HandleVertex vertexHandle)
{
return EnVertexIncomingHalfEdge(vertexHandle).Select(handleHalfEdge => _LhedgePtrCont[handleHalfEdge]._he).AsEnumerable();
}
/// <summary>
/// Iterator.
/// Circulate around a given vertex and enumerate all faces adjacent to the center vertex.
/// </summary>
/// <param name="hv">A handle to a vertex to use as a 'center' vertex.</param>
/// <param name="vertexHandle">Handle to the vertex to do this operation on.</param>
/// <returns>An Enumerable of HalfEdge handles to be used in loops, etc.</returns>
public IEnumerable<HandleFace> EnVertexAdjacentFaces(HandleVertex vertexHandle)
{
return EnVertexIncomingHalfEdge(vertexHandle).Select(handleHalfEdge => _LhedgePtrCont[handleHalfEdge]._f).AsEnumerable();
}
/// <summary>
/// Iterator.
/// Circulate around a given vertex and enumerate all vertices connected by a direct edge.
/// </summary>
/// <param name="vertexHandle">A handle to a vertex to use as a 'center' vertex.</param>
/// <returns>An Enumerable of VertexHandles to be used in loops, etc.</returns>
public IEnumerable<HandleVertex> EnStarVertexVertex(HandleVertex vertexHandle)
{
return EnVertexIncomingHalfEdge(vertexHandle).Select(handleHalfEdge => _LhedgePtrCont[_LhedgePtrCont[handleHalfEdge]._he]._v).AsEnumerable();
}
/// <summary>
/// Establishes a connection between two vertices.
/// 1) Creates two half-edges
/// 2) Fills them with information
/// 3) Creates an edge pointer container and adds it to the geo container.
/// 4) returns a handle to an edge
/// </summary>
/// <param name="fromVert">HandleVertex from which vertex</param>
/// <param name="toVert">Handlevertex to which vertex</param>
/// <returns>Returns a handle to the half-edge that has just been inserted</returns>
public HandleHalfEdge CreateConnection(HandleVertex fromVert, HandleVertex toVert)
{
// Check if the connection does already exist.
HandleEdge existingEdge = DoesConnectionExist(fromVert, toVert);
if (existingEdge != -1)
{
return ReuseExistingConnection(existingEdge, fromVert, toVert);
}
else
{
return CreateAllNewConnection(fromVert, toVert);
}
}
/// <summary>
/// This method calculates vertex normals for a specific vertex in the geometry and inserts them at the corresponding half-edges on the correct faces.
/// This method uses an angle based algorithm to determine whether to calculate with another faces normal or not.
/// </summary>
/// <param name="vertexHandle">A handle for the vertex to calc the normals for.</param>
public void CalcVertexNormal(HandleVertex vertexHandle)
{
List<HandleHalfEdge> EincomingHEdges = EnVertexIncomingHalfEdge(vertexHandle).ToList();
// Loop over every incoming half-edge.
foreach (HandleHalfEdge handleHedge in EincomingHEdges)
{
int hedgeIndex = handleHedge;
// Check if the half-edge is pointing to a face.
int faceIndex = _LhedgePtrCont[hedgeIndex]._f;
if (faceIndex == -1)
return;
float3 currentFaceNormal = _LfaceNormals[_LfacePtrCont[faceIndex]._fn];
float3 normalAggregate = new float3();
// Loop over every incoming half-edge again, so we can compare the angles between the current one and all the others.
// We do this to decide which normal should be added to the sum and which not.
foreach (int eincomingHEdge in EincomingHEdges)
{
// Add the current normal if the index is on it and do not compare any angles etc.
if (eincomingHEdge == hedgeIndex)
{
normalAggregate += currentFaceNormal;
continue;
}
// Stop when the current half-edge is not pointing to a face.
int faceIndex2 = _LhedgePtrCont[eincomingHEdge]._f;
if (faceIndex2 == -1)
continue;
float3 normalToCompare = _LfaceNormals[_LfacePtrCont[faceIndex2]._fn];
float dot = float3.Dot(currentFaceNormal, normalToCompare);
if (System.Math.Acos(dot) * _constPiFactor < _SmoothingAngle)
normalAggregate += float3.Add(normalAggregate, normalToCompare);
}
_LVertexNormals.Add(float3.NormalizeFast(normalAggregate));
HEdgePtrCont currentHedge = _LhedgePtrCont[hedgeIndex];
_LhedgePtrCont[hedgeIndex] = new HEdgePtrCont()
{
_f = currentHedge._f,
_he = currentHedge._he,
_nhe = currentHedge._nhe,
_v = currentHedge._v,
_vn = new HandleVertexNormal(_LVertexNormals.Count - 1),
_vuv = currentHedge._vuv
};
}
}
/// <summary>
/// Adds a vertex to the geometry container.
/// Will return a handle to the newly inserted or still existing vertex.
/// </summary>
/// <param name="val">float3 value to insert</param>
/// <returns>Returns a handle to the just inserted vertex or a handle to an existing one because the given one was already inserterd.</returns>
public HandleVertex AddVertex(float3 val)
{
int index = DoesVertexExist(val);
HandleVertex hvToAdd = new HandleVertex() { _DataIndex = -1 };
// When vertex does not exist - insert it
if (index == -1)
{
_LvertexVal.Add(val);
_LvertexPtrCont.Add(
new VertexPtrCont()
{
_h = new HandleHalfEdge()
{
_DataIndex = -1
}
}
);
hvToAdd = new HandleVertex() { _DataIndex = _LvertexPtrCont.Count - 1 };
}
else
{
HandleVertex vHndl = new HandleVertex();
vHndl._DataIndex = index;
hvToAdd = vHndl;
}
if (!_LverticeHndl.Contains(hvToAdd))
{
_LverticeHndl.Add(hvToAdd);
}
else
{
if (LFGMessages._DEBUGOUTPUT)
{
Debug.WriteLine("$$$ Vertex has been already inserted!");
}
}
return hvToAdd;
}
