// smooths embedded loop in mesh, by first smoothing edge loop and then
// smoothing vertex neighbourhood
// [TODO] geodesic nbrhoold instead of # of rings
// [TODO] reprojection?
public static void smooth_loop(DMesh3 mesh, EdgeLoop loop, int nRings)
{
MeshFaceSelection roi_t = new MeshFaceSelection(mesh);
roi_t.SelectVertexOneRings(loop.Vertices);
for (int i = 0; i < nRings; ++i)
{
roi_t.ExpandToOneRingNeighbours();
}
roi_t.LocalOptimize(true, true);
MeshVertexSelection roi_v = new MeshVertexSelection(mesh);
roi_v.SelectTriangleVertices(roi_t.ToArray());
roi_v.Deselect(loop.Vertices);
MeshLoopSmooth loop_smooth = new MeshLoopSmooth(mesh, loop);
loop_smooth.Rounds = 1;
MeshIterativeSmooth mesh_smooth = new MeshIterativeSmooth(mesh, roi_v.ToArray(), true);
mesh_smooth.Rounds = 1;
for (int i = 0; i < 10; ++i)
{
loop_smooth.Smooth();
mesh_smooth.Smooth();
}
}
// local mesh smooth applied to all vertices in N-rings around input list
public static void smooth_region(DMesh3 mesh, IEnumerable <int> vertices, int nRings)
{
MeshFaceSelection roi_t = new MeshFaceSelection(mesh);
roi_t.SelectVertexOneRings(vertices);
for (int i = 0; i < nRings; ++i)
{
roi_t.ExpandToOneRingNeighbours();
}
roi_t.LocalOptimize(true, true);
MeshVertexSelection roi_v = new MeshVertexSelection(mesh);
roi_v.SelectTriangleVertices(roi_t.ToArray());
MeshIterativeSmooth mesh_smooth = new MeshIterativeSmooth(mesh, roi_v.ToArray(), true);
mesh_smooth.Alpha = 0.2f;
mesh_smooth.Rounds = 10;
mesh_smooth.Smooth();
}
public virtual bool Extrude()
{
MeshEditor editor = new MeshEditor(Mesh);
editor.SeparateTriangles(Triangles, true, out EdgePairs);
MeshNormals normals = null;
bool bHaveNormals = Mesh.HasVertexNormals;
if (!bHaveNormals)
{
normals = new MeshNormals(Mesh);
normals.Compute();
}
ExtrudeVertices = new MeshVertexSelection(Mesh);
ExtrudeVertices.SelectTriangleVertices(Triangles);
Vector3d[] NewVertices = new Vector3d[ExtrudeVertices.Count];
int k = 0;
foreach (int vid in ExtrudeVertices)
{
Vector3d v = Mesh.GetVertex(vid);
Vector3f n = (bHaveNormals) ? Mesh.GetVertexNormal(vid) : (Vector3f)normals.Normals[vid];
NewVertices[k++] = ExtrudedPositionF(v, n, vid);
}
k = 0;
foreach (int vid in ExtrudeVertices)
{
Mesh.SetVertex(vid, NewVertices[k++]);
}
SetGroupID = Group.GetGroupID(Mesh);
JoinTriangles = editor.StitchUnorderedEdges(EdgePairs, SetGroupID);
return(true);
}
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;
}
/// <summary>
/// Apply LaplacianMeshSmoother to subset of mesh triangles.
/// border of subset always has soft constraint with borderWeight,
/// but is then snapped back to original vtx pos after solve.
/// nConstrainLoops inner loops are also soft-constrained, with weight falloff via square roots (defines continuity)
/// interiorWeight is soft constraint added to all vertices
/// </summary>
public static void RegionSmooth(DMesh3 mesh, IEnumerable <int> triangles,
int nConstrainLoops,
int nIncludeExteriorRings,
bool bPreserveExteriorRings,
double borderWeight = 10.0, double interiorWeight = 0.0)
{
HashSet <int> fixedVerts = new HashSet <int>();
if (nIncludeExteriorRings > 0)
{
MeshFaceSelection expandTris = new MeshFaceSelection(mesh);
expandTris.Select(triangles);
if (bPreserveExteriorRings)
{
MeshEdgeSelection bdryEdges = new MeshEdgeSelection(mesh);
bdryEdges.SelectBoundaryTriEdges(expandTris);
expandTris.ExpandToOneRingNeighbours(nIncludeExteriorRings);
MeshVertexSelection startVerts = new MeshVertexSelection(mesh);
startVerts.SelectTriangleVertices(triangles);
startVerts.DeselectEdges(bdryEdges);
MeshVertexSelection expandVerts = new MeshVertexSelection(mesh, expandTris);
foreach (int vid in expandVerts)
{
if (startVerts.IsSelected(vid) == false)
{
fixedVerts.Add(vid);
}
}
}
else
{
expandTris.ExpandToOneRingNeighbours(nIncludeExteriorRings);
}
triangles = expandTris;
}
RegionOperator region = new RegionOperator(mesh, triangles);
DSubmesh3 submesh = region.Region;
DMesh3 smoothMesh = submesh.SubMesh;
LaplacianMeshSmoother smoother = new LaplacianMeshSmoother(smoothMesh);
// map fixed verts to submesh
HashSet <int> subFixedVerts = new HashSet <int>();
foreach (int base_vid in fixedVerts)
{
subFixedVerts.Add(submesh.MapVertexToSubmesh(base_vid));
}
// constrain borders
double w = borderWeight;
HashSet <int> constrained = (submesh.BaseBorderV.Count > 0) ? new HashSet <int>() : null;
foreach (int base_vid in submesh.BaseBorderV)
{
int sub_vid = submesh.BaseToSubV[base_vid];
smoother.SetConstraint(sub_vid, smoothMesh.GetVertex(sub_vid), w, true);
if (constrained != null)
{
constrained.Add(sub_vid);
}
}
if (constrained.Count > 0)
{
w = Math.Sqrt(w);
for (int k = 0; k < nConstrainLoops; ++k)
{
HashSet <int> next_layer = new HashSet <int>();
foreach (int sub_vid in constrained)
{
foreach (int nbr_vid in smoothMesh.VtxVerticesItr(sub_vid))
{
if (constrained.Contains(nbr_vid) == false)
{
if (smoother.IsConstrained(nbr_vid) == false)
{
smoother.SetConstraint(nbr_vid, smoothMesh.GetVertex(nbr_vid), w, subFixedVerts.Contains(nbr_vid));
}
next_layer.Add(nbr_vid);
}
}
}
constrained.UnionWith(next_layer);
w = Math.Sqrt(w);
}
}
// soft constraint on all interior vertices, if requested
if (interiorWeight > 0)
{
foreach (int vid in smoothMesh.VertexIndices())
{
if (smoother.IsConstrained(vid) == false)
{
smoother.SetConstraint(vid, smoothMesh.GetVertex(vid), interiorWeight, subFixedVerts.Contains(vid));
}
}
}
else if (subFixedVerts.Count > 0)
{
foreach (int vid in subFixedVerts)
{
if (smoother.IsConstrained(vid) == false)
{
smoother.SetConstraint(vid, smoothMesh.GetVertex(vid), 0, true);
}
}
}
smoother.SolveAndUpdateMesh();
region.BackPropropagateVertices(true);
}
