public void SelectTriangleEdges(IEnumerable <int> triangles)
{
foreach (int tid in triangles)
{
Index3i et = Mesh.GetTriEdges(tid);
add(et.a); add(et.b); add(et.c);
}
}
public static void TrianglesToEdges(DMesh3 mesh, HashSet <int> triangles, HashSet <int> edges)
{
foreach (int tid in triangles)
{
Index3i te = mesh.GetTriEdges(tid);
edges.Add(te.a); edges.Add(te.b); edges.Add(te.c);
}
}
public void ComputeBoundaryInfo(IEnumerable <int> triangles, int tri_count)
{
// set of base-mesh triangles that are in submesh
IndexFlagSet sub_tris = new IndexFlagSet(BaseMesh.MaxTriangleID, tri_count);
foreach (int ti in triangles)
{
sub_tris[ti] = true;
}
BaseBorderV = new IndexHashSet();
BaseBorderE = new IndexHashSet();
BaseBoundaryE = new IndexHashSet();
// Iterate through edges in submesh roi on base mesh. If
// one of the tris of the edge is not in submesh roi, then this
// is a boundary edge.
//
// (edge iteration via triangle iteration processes each internal edge twice...)
foreach (int ti in triangles)
{
Index3i tedges = BaseMesh.GetTriEdges(ti);
for (int j = 0; j < 3; ++j)
{
int eid = tedges[j];
Index2i tris = BaseMesh.GetEdgeT(eid);
if (tris.b == DMesh3.InvalidID || sub_tris[tris.a] != sub_tris[tris.b])
{
if (tris.b == DMesh3.InvalidID)
{
BaseBoundaryE[eid] = true;
}
else
{
BaseBorderE[eid] = true;
}
Index2i ve = BaseMesh.GetEdgeV(eid);
BaseBorderV[ve.a] = true;
BaseBorderV[ve.b] = true;
}
}
}
}
public MeshRegionBoundaryLoops(DMesh3 mesh, int[] RegionTris, bool bAutoCompute = true)
{
this.Mesh = mesh;
// make flag set for included triangles
triangles = new IndexFlagSet(mesh.MaxTriangleID, RegionTris.Length);
for (int i = 0; i < RegionTris.Length; ++i)
{
triangles[RegionTris[i]] = true;
}
// make flag set for included edges
// NOTE: this currently processes non-boundary-edges twice. Could
// avoid w/ another IndexFlagSet, but the check is inexpensive...
edges = new IndexFlagSet(mesh.MaxEdgeID, RegionTris.Length);
for (int i = 0; i < RegionTris.Length; ++i)
{
int tid = RegionTris[i];
Index3i te = Mesh.GetTriEdges(tid);
for (int j = 0; j < 3; ++j)
{
int eid = te[j];
if (!edges.Contains(eid))
{
Index2i et = mesh.GetEdgeT(eid);
if (et.b == DMesh3.InvalidID || triangles[et.a] != triangles[et.b])
{
edges.Add(eid);
}
}
}
}
if (bAutoCompute)
{
Compute();
}
}
// convert face selection to edge selection. Require at least minCount tris of edge to be selected
public MeshEdgeSelection(DMesh3 mesh, MeshFaceSelection convertT, int minCount = 1) : this(mesh)
{
minCount = MathUtil.Clamp(minCount, 1, 2);
if (minCount == 1)
{
foreach (int tid in convertT)
{
Index3i te = mesh.GetTriEdges(tid);
add(te.a); add(te.b); add(te.c);
}
}
else
{
foreach (int eid in mesh.EdgeIndices())
{
Index2i et = mesh.GetEdgeT(eid);
if (convertT.IsSelected(et.a) && convertT.IsSelected(et.b))
{
add(eid);
}
}
}
}
protected void compute_full(IEnumerable <int> Triangles, bool bIsFullMeshHint = false)
{
Graph = new DGraph3();
if (WantGraphEdgeInfo)
{
GraphEdges = new DVector <GraphEdgeInfo>();
}
Vertices = new Dictionary <Vector3d, int>();
// multithreaded precomputation of per-vertex values
double[] vertex_values = null;
if (PrecomputeVertexValues)
{
vertex_values = new double[Mesh.MaxVertexID];
IEnumerable <int> verts = Mesh.VertexIndices();
if (bIsFullMeshHint == false)
{
MeshVertexSelection vertices = new MeshVertexSelection(Mesh);
vertices.SelectTriangleVertices(Triangles);
verts = vertices;
}
gParallel.ForEach(verts, (vid) => {
vertex_values[vid] = ValueF(Mesh.GetVertex(vid));
});
VertexValueF = (vid) => { return(vertex_values[vid]); };
}
foreach (int tid in Triangles)
{
Vector3dTuple3 tv = new Vector3dTuple3();
Mesh.GetTriVertices(tid, ref tv.V0, ref tv.V1, ref tv.V2);
Index3i triVerts = Mesh.GetTriangle(tid);
Vector3d f = (VertexValueF != null) ?
new Vector3d(VertexValueF(triVerts.a), VertexValueF(triVerts.b), VertexValueF(triVerts.c))
: new Vector3d(ValueF(tv.V0), ValueF(tv.V1), ValueF(tv.V2));
// round f to 0 within epsilon?
if (f.x < 0 && f.y < 0 && f.z < 0)
{
continue;
}
if (f.x > 0 && f.y > 0 && f.z > 0)
{
continue;
}
Index3i triEdges = Mesh.GetTriEdges(tid);
if (f.x * f.y * f.z == 0)
{
int z0 = (f.x == 0) ? 0 : ((f.y == 0) ? 1 : 2);
int i1 = (z0 + 1) % 3, i2 = (z0 + 2) % 3;
if (f[i1] * f[i2] > 0)
{
continue; // single-vertex-crossing case, skip here and let other edges catch it
}
if (f[i1] == 0 || f[i2] == 0)
{
// on-edge case
int z1 = f[i1] == 0 ? i1 : i2;
if ((z0 + 1) % 3 != z1)
{
int tmp = z0; z0 = z1; z1 = tmp; // catch reverse-orientation cases
}
int e0 = add_or_append_vertex(Mesh.GetVertex(triVerts[z0]));
int e1 = add_or_append_vertex(Mesh.GetVertex(triVerts[z1]));
int graph_eid = Graph.AppendEdge(e0, e1, (int)TriangleCase.OnEdge);
if (graph_eid >= 0 && WantGraphEdgeInfo)
{
add_on_edge(graph_eid, tid, triEdges[z0], new Index2i(e0, e1));
}
}
else
{
// edge/vertex case
Util.gDevAssert(f[i1] * f[i2] < 0);
int vert_vid = add_or_append_vertex(Mesh.GetVertex(triVerts[z0]));
int i = i1, j = i2;
if (triVerts[j] < triVerts[i])
{
int tmp = i; i = j; j = tmp;
}
Vector3d cross = find_crossing(tv[i], tv[j], f[i], f[j]);
int cross_vid = add_or_append_vertex(cross);
add_edge_pos(triVerts[i], triVerts[j], cross);
int graph_eid = Graph.AppendEdge(vert_vid, cross_vid, (int)TriangleCase.EdgeVertex);
if (graph_eid >= 0 && WantGraphEdgeInfo)
{
add_edge_vert(graph_eid, tid, triEdges[(z0 + 1) % 3], triVerts[z0], new Index2i(vert_vid, cross_vid));
}
}
}
else
{
Index3i cross_verts = Index3i.Min;
int less_than = 0;
for (int tei = 0; tei < 3; ++tei)
{
int i = tei, j = (tei + 1) % 3;
if (f[i] < 0)
{
less_than++;
}
if (f[i] * f[j] > 0)
{
continue;
}
if (triVerts[j] < triVerts[i])
{
int tmp = i; i = j; j = tmp;
}
Vector3d cross = find_crossing(tv[i], tv[j], f[i], f[j]);
cross_verts[tei] = add_or_append_vertex(cross);
add_edge_pos(triVerts[i], triVerts[j], cross);
}
int e0 = (cross_verts.a == int.MinValue) ? 1 : 0;
int e1 = (cross_verts.c == int.MinValue) ? 1 : 2;
if (e0 == 0 && e1 == 2) // preserve orientation order
{
e0 = 2; e1 = 0;
}
// preserving orientation does not mean we get a *consistent* orientation across faces.
// To do that, we need to assign "sides". Either we have 1 less-than-0 or 1 greater-than-0 vtx.
// Arbitrary decide that we want loops oriented like bdry loops would be if we discarded less-than side.
// In that case, when we are "cutting off" one vertex, orientation would end up flipped
if (less_than == 1)
{
int tmp = e0; e0 = e1; e1 = tmp;
}
int ev0 = cross_verts[e0];
int ev1 = cross_verts[e1];
// [RMS] if function is garbage, we can end up w/ case where both crossings
// happen at same vertex, even though values are not the same (eg if
// some values are double.MaxValue). We will just fail in these cases.
if (ev0 != ev1)
{
Util.gDevAssert(ev0 != int.MinValue && ev1 != int.MinValue);
int graph_eid = Graph.AppendEdge(ev0, ev1, (int)TriangleCase.EdgeEdge);
if (graph_eid >= 0 && WantGraphEdgeInfo)
{
add_edge_edge(graph_eid, tid, new Index2i(triEdges[e0], triEdges[e1]), new Index2i(ev0, ev1));
}
}
}
}
Vertices = null;
}
protected void compute_full(IEnumerable <int> Triangles)
{
Graph = new DGraph3();
if (WantGraphEdgeInfo)
{
GraphEdges = new DVector <GraphEdgeInfo>();
}
Vertices = new Dictionary <Vector3d, int>();
foreach (int tid in Triangles)
{
Vector3dTuple3 tv = new Vector3dTuple3();
Mesh.GetTriVertices(tid, ref tv.V0, ref tv.V1, ref tv.V2);
Vector3d f = new Vector3d(ValueF(tv.V0), ValueF(tv.V1), ValueF(tv.V2));
// round f to 0 within epsilon?
if (f.x < 0 && f.y < 0 && f.z < 0)
{
continue;
}
if (f.x > 0 && f.y > 0 && f.z > 0)
{
continue;
}
Index3i triVerts = Mesh.GetTriangle(tid);
Index3i triEdges = Mesh.GetTriEdges(tid);
if (f.x * f.y * f.z == 0)
{
int z0 = (f.x == 0) ? 0 : ((f.y == 0) ? 1 : 2);
int i1 = (z0 + 1) % 3, i2 = (z0 + 2) % 3;
if (f[i1] * f[i2] > 0)
{
continue; // single-vertex-crossing case, skip here and let other edges catch it
}
if (f[i1] == 0 || f[i2] == 0)
{
// on-edge case
int z1 = f[i1] == 0 ? i1 : i2;
int e0 = add_or_append_vertex(Mesh.GetVertex(triVerts[z0]));
int e1 = add_or_append_vertex(Mesh.GetVertex(triVerts[z1]));
int graph_eid = Graph.AppendEdge(e0, e1, (int)TriangleCase.OnEdge);
if (WantGraphEdgeInfo)
{
add_on_edge(graph_eid, tid, triEdges[z0]);
}
}
else
{
// edge/vertex case
Util.gDevAssert(f[i1] * f[i2] < 0);
int vert_vid = add_or_append_vertex(Mesh.GetVertex(triVerts[z0]));
int i = i1, j = i2;
if (triVerts[j] < triVerts[i])
{
int tmp = i; i = j; j = tmp;
}
Vector3d cross = find_crossing(tv[i], tv[j], f[i], f[j]);
int cross_vid = add_or_append_vertex(cross);
int graph_eid = Graph.AppendEdge(vert_vid, cross_vid, (int)TriangleCase.EdgeVertex);
if (WantGraphEdgeInfo)
{
add_edge_edge(graph_eid, tid, new Index2i(triEdges[(z0 + 1) % 3], triVerts[z0]));
}
}
}
else
{
Index3i cross_verts = Index3i.Min;
for (int ti = 0; ti < 3; ++ti)
{
int i = ti, j = (ti + 1) % 3;
if (f[i] * f[j] > 0)
{
continue;
}
if (triVerts[j] < triVerts[i])
{
int tmp = i; i = j; j = tmp;
}
Vector3d cross = find_crossing(tv[i], tv[j], f[i], f[j]);
cross_verts[ti] = add_or_append_vertex(cross);
}
int e0 = (cross_verts.a == int.MinValue) ? 1 : 0;
int e1 = (cross_verts.c == int.MinValue) ? 1 : 2;
int ev0 = cross_verts[e0];
int ev1 = cross_verts[e1];
Util.gDevAssert(ev0 != int.MinValue && ev1 != int.MinValue);
int graph_eid = Graph.AppendEdge(ev0, ev1, (int)TriangleCase.EdgeEdge);
if (WantGraphEdgeInfo)
{
add_edge_edge(graph_eid, tid, new Index2i(triEdges[e0], triEdges[e1]));
}
}
}
Vertices = null;
}
/// <summary>
/// Disconnect the given triangles from their neighbours, by duplicating "boundary" vertices, ie
/// vertices on edges for which one triangle is in-set and the other is not.
/// If bComputeEdgePairs is true, we return list of old/new edge pairs (useful for stitching)
/// [TODO] currently boundary-edge behaviour is to *not* duplicate boundary verts
/// </summary>
public bool SeparateTriangles(IEnumerable <int> triangles, bool bComputeEdgePairs, out List <Index2i> EdgePairs)
{
HashSet <int> in_set = new HashSet <int>(triangles);
Dictionary <int, int> VertexMap = new Dictionary <int, int>();
EdgePairs = null;
HashSet <int> edges = null;
List <Index2i> OldEdgeVerts = null;
if (bComputeEdgePairs)
{
EdgePairs = new List <Index2i>();
edges = new HashSet <int>();
OldEdgeVerts = new List <Index2i>();
}
// duplicate vertices on edges that are on boundary of triangles roi
foreach (int tid in triangles)
{
Index3i te = Mesh.GetTriEdges(tid);
for (int j = 0; j < 3; ++j)
{
Index2i et = Mesh.GetEdgeT(te[j]);
// [TODO] what about behavior where we want to also duplicate boundary verts??
if (et.b == DMesh3.InvalidID || (et.a == tid && in_set.Contains(et.b)) || (et.b == tid && in_set.Contains(et.a)))
{
te[j] = -1;
}
}
for (int j = 0; j < 3; ++j)
{
if (te[j] == -1)
{
continue;
}
Index2i ev = Mesh.GetEdgeV(te[j]);
if (VertexMap.ContainsKey(ev.a) == false)
{
VertexMap[ev.a] = Mesh.AppendVertex(Mesh, ev.a);
}
if (VertexMap.ContainsKey(ev.b) == false)
{
VertexMap[ev.b] = Mesh.AppendVertex(Mesh, ev.b);
}
if (bComputeEdgePairs && edges.Contains(te[j]) == false)
{
edges.Add(te[j]);
OldEdgeVerts.Add(ev);
EdgePairs.Add(new Index2i(te[j], -1));
}
}
}
// update triangles
foreach (int tid in triangles)
{
Index3i tv = Mesh.GetTriangle(tid);
Index3i tv_new = tv;
for (int j = 0; j < 3; ++j)
{
int newv;
if (VertexMap.TryGetValue(tv[j], out newv))
{
tv_new[j] = newv;
}
}
if (tv_new != tv)
{
Mesh.SetTriangle(tid, tv_new);
}
}
if (bComputeEdgePairs)
{
for (int k = 0; k < EdgePairs.Count; ++k)
{
Index2i old_ev = OldEdgeVerts[k];
int new_a = VertexMap[old_ev.a];
int new_b = VertexMap[old_ev.b];
int new_eid = Mesh.FindEdge(new_a, new_b);
Util.gDevAssert(new_eid != DMesh3.InvalidID);
EdgePairs[k] = new Index2i(EdgePairs[k].a, new_eid);
}
}
return(true);
}
