// 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();
}
}
// This function does local remeshing around a boundary loop within a fixed # of
// rings, to try to 'massage' it into a cleaner shape/topology
// [TODO] use geodesic distance instead of fixed # of rings?
public static void cleanup_boundary(DMesh3 mesh, EdgeLoop loop, double target_edge_len, int nRings = 3)
{
Debug.Assert(loop.IsBoundaryLoop());
MeshFaceSelection roi = new MeshFaceSelection(mesh);
roi.SelectVertexOneRings(loop.Vertices);
for (int i = 0; i < nRings; ++i)
{
roi.ExpandToOneRingNeighbours();
}
roi.LocalOptimize(true, true);
RegionRemesher r = new RegionRemesher(mesh, roi.ToArray());
r.Precompute();
r.EnableFlips = r.EnableSplits = r.EnableCollapses = true;
r.MinEdgeLength = target_edge_len;
r.MaxEdgeLength = 2 * target_edge_len;
r.EnableSmoothing = true;
r.SmoothSpeedT = 0.1f;
for (int k = 0; k < nRings * 3; ++k)
{
r.BasicRemeshPass();
}
Debug.Assert(mesh.CheckValidity());
r.BackPropropagate();
}
/// <summary>
/// Automatically construct fastest projection target for region of mesh
/// </summary>
public static MeshProjectionTarget Auto(DMesh3 mesh, IEnumerable <int> triangles, int nExpandRings = 5)
{
var targetRegion = new MeshFaceSelection(mesh);
targetRegion.Select(triangles);
targetRegion.ExpandToOneRingNeighbours(nExpandRings);
var submesh = new DSubmesh3(mesh, targetRegion);
return(new MeshProjectionTarget(submesh.SubMesh));
}
// This function does local remeshing around a boundary loop within a fixed # of
// rings, to try to 'massage' it into a cleaner shape/topology.
// The result_edges list is the mapped edges of loop on the resulting mesh, but it is *not* in-order
// [TODO] use geodesic distance instead of fixed # of rings?
public static void cleanup_boundary(DMesh3 mesh, EdgeLoop loop, double target_edge_len, out List <int> result_edges, int nRings = 3)
{
Debug.Assert(loop.IsBoundaryLoop());
var roi = new MeshFaceSelection(mesh);
roi.SelectVertexOneRings(loop.Vertices);
for (int i = 0; i < nRings; ++i)
{
roi.ExpandToOneRingNeighbours();
}
roi.LocalOptimize(true, true);
var r = new RegionRemesher(mesh, roi.ToArray());
// tag the input loop edges in the remesher, so that we can find this loop afterwards
int[] init_loop_edges = new int[loop.EdgeCount];
Array.Copy(loop.Edges, init_loop_edges, loop.EdgeCount);
r.Region.MapEdgesToSubmesh(init_loop_edges);
MeshConstraintUtil.AddTrackedEdges(r.Constraints, init_loop_edges, 100);
//foreach (int eid in init_loop_edges)
// Debug.Assert(r.Region.SubMesh.IsBoundaryEdge(eid));
r.Precompute();
r.EnableFlips = r.EnableSplits = r.EnableCollapses = true;
r.MinEdgeLength = target_edge_len;
r.MaxEdgeLength = 2 * target_edge_len;
r.EnableSmoothing = true;
r.SmoothSpeedT = 0.1f;
for (int k = 0; k < nRings * 3; ++k)
{
r.BasicRemeshPass();
}
Debug.Assert(mesh.CheckValidity());
// extract the edges we tagged (they are unordered)
List <int> new_loop_edges = r.Constraints.FindConstrainedEdgesBySetID(100);
//foreach (int eid in new_loop_edges)
// Debug.Assert(r.Region.SubMesh.IsBoundaryEdge(eid));
r.BackPropropagate();
// map the extracted edges back to the backpropped input mesh
result_edges = MeshIndexUtil.MapEdgesViaVertexMap(r.ReinsertSubToBaseMapV, r.Region.SubMesh, r.BaseMesh, new_loop_edges);
//foreach (int eid in result_edges)
// Debug.Assert(mesh.IsBoundaryEdge(eid));
}
// assumes PathT is contains set of triangles
// that are fully connected, ie a flood-fill cannot escape!
void find_interior_from_tris()
{
var pathNbrs = new MeshFaceSelection(Mesh);
pathNbrs.Select(PathT);
pathNbrs.ExpandToOneRingNeighbours();
pathNbrs.Deselect(PathT);
var connected = new MeshConnectedComponents(Mesh);
connected.FilterSet = pathNbrs;
connected.FindConnectedT();
int N = connected.Count;
if (N < 2)
{
throw new Exception("MeshFacesFromLoop.find_interior: only found one connected component!");
}
// only consider 2 largest. somehow we are sometimes getting additional
// "outside" components, and if we do growing from there, it covers whole mesh??
connected.SortByCount(false);
N = 2;
var selections = new MeshFaceSelection[N];
bool[] done = new bool[N];
for (int i = 0; i < N; ++i)
{
selections[i] = new MeshFaceSelection(Mesh);
selections[i].Select(connected.Components[i].Indices);
done[i] = false;
}
var border_tris = new HashSet <int>(PathT);
Func <int, bool> borderF = (tid) => { return(border_tris.Contains(tid) == false); };
// 'largest' flood fill is expensive...if we had a sense of tooth size we could reduce cost?
for (int i = 0; i < N; ++i)
{
selections[i].FloodFill(connected.Components[i].Indices, borderF);
}
Array.Sort(selections, (a, b) => { return(a.Count.CompareTo(b.Count)); });
InteriorT = new List <int>(selections[0]);
}
// 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();
}
/// <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);
}
public virtual bool Trim()
{
if (Spatial == null)
{
Spatial = new DMeshAABBTree3(new DMesh3(Mesh, false, MeshComponents.None));
Spatial.Build();
}
if (seed_tri == -1)
{
seed_tri = Spatial.FindNearestTriangle(seed_pt);
}
var loop = new MeshFacesFromLoop(Mesh, TrimLine, Spatial, seed_tri);
MeshFaceSelection selection = loop.ToSelection();
selection.LocalOptimize(true, true);
var editor = new MeshEditor(Mesh);
editor.RemoveTriangles(selection, true);
var components = new MeshConnectedComponents(Mesh);
components.FindConnectedT();
if (components.Count > 1)
{
int keep = components.LargestByCount;
for (int i = 0; i < components.Count; ++i)
{
if (i != keep)
{
editor.RemoveTriangles(components[i].Indices, true);
}
}
}
editor.RemoveAllBowtieVertices(true);
var loops = new MeshBoundaryLoops(Mesh);
bool loopsOK = false;
try
{
loopsOK = loops.Compute();
}
catch (Exception)
{
return(false);
}
if (!loopsOK)
{
return(false);
}
// [TODO] to support trimming mesh w/ existing holes, we need to figure out which
// loop we created in RemoveTriangles above!
if (loops.Count > 1)
{
return(false);
}
int[] loopVerts = loops[0].Vertices;
var borderTris = new MeshFaceSelection(Mesh);
borderTris.SelectVertexOneRings(loopVerts);
borderTris.ExpandToOneRingNeighbours(RemeshBorderRings);
var remesh = new RegionRemesher(Mesh, borderTris.ToArray());
remesh.Region.MapVerticesToSubmesh(loopVerts);
double target_len = TargetEdgeLength;
if (target_len <= 0)
{
double mine, maxe, avge;
MeshQueries.EdgeLengthStatsFromEdges(Mesh, loops[0].Edges, out mine, out maxe, out avge);
target_len = avge;
}
var meshTarget = new MeshProjectionTarget(Spatial.Mesh, Spatial);
remesh.SetProjectionTarget(meshTarget);
remesh.SetTargetEdgeLength(target_len);
remesh.SmoothSpeedT = SmoothingAlpha;
var curveTarget = new DCurveProjectionTarget(TrimLine);
var multiTarget = new SequentialProjectionTarget(curveTarget, meshTarget);
int set_id = 3;
MeshConstraintUtil.ConstrainVtxLoopTo(remesh, loopVerts, multiTarget, set_id);
for (int i = 0; i < RemeshRounds; ++i)
{
remesh.BasicRemeshPass();
}
remesh.BackPropropagate();
// [TODO] output loop somehow...use MeshConstraints.FindConstrainedEdgesBySetID(set_id)...
return(true);
} // Trim()
public void Close_Flat()
{
double minlen, maxlen, avglen;
MeshQueries.EdgeLengthStats(Mesh, out minlen, out maxlen, out avglen, 1000);
double target_edge_len = (TargetEdgeLen <= 0) ? avglen : TargetEdgeLen;
// massage around boundary loop
List <int> refinedBorderEdges;
cleanup_boundary(Mesh, InitialBorderLoop, avglen, out refinedBorderEdges, 3);
// find new border loop. try to find new loop containing edges from loop we refined in cleanup_boundary,
// if that fails just use largest loop.
MeshBoundaryLoops loops = new MeshBoundaryLoops(Mesh);
int iloop = loops.FindLoopContainingEdge(refinedBorderEdges[0]);
if (iloop == -1)
{
iloop = loops.MaxVerticesLoopIndex;
}
EdgeLoop fill_loop = loops.Loops[iloop];
int extrude_group = (ExtrudeGroup == -1) ? Mesh.AllocateTriangleGroup() : ExtrudeGroup;
int fill_group = (FillGroup == -1) ? Mesh.AllocateTriangleGroup() : FillGroup;
// decide on projection plane
//AxisAlignedBox3d loopbox = fill_loop.GetBounds();
//Vector3d topPt = loopbox.Center;
//if ( bIsUpper ) {
// topPt.y = loopbox.Max.y + 0.25 * dims.y;
//} else {
// topPt.y = loopbox.Min.y - 0.25 * dims.y;
//}
//Frame3f plane = new Frame3f((Vector3f)topPt);
// extrude loop to this plane
MeshExtrudeLoop extrude = new MeshExtrudeLoop(Mesh, fill_loop);
extrude.PositionF = (v, n, i) => {
return(FlatClosePlane.ProjectToPlane((Vector3f)v, 1));
};
extrude.Extrude(extrude_group);
MeshValidation.IsBoundaryLoop(Mesh, extrude.NewLoop);
Debug.Assert(Mesh.CheckValidity());
// smooth the extrude loop
MeshLoopSmooth loop_smooth = new MeshLoopSmooth(Mesh, extrude.NewLoop);
loop_smooth.ProjectF = (v, i) => {
return(FlatClosePlane.ProjectToPlane((Vector3f)v, 1));
};
loop_smooth.Alpha = 0.5f;
loop_smooth.Rounds = 100;
loop_smooth.Smooth();
Debug.Assert(Mesh.CheckValidity());
// fill result
SimpleHoleFiller filler = new SimpleHoleFiller(Mesh, extrude.NewLoop);
filler.Fill(fill_group);
Debug.Assert(Mesh.CheckValidity());
// make selection for remesh region
MeshFaceSelection remesh_roi = new MeshFaceSelection(Mesh);
remesh_roi.Select(extrude.NewTriangles);
remesh_roi.Select(filler.NewTriangles);
remesh_roi.ExpandToOneRingNeighbours();
remesh_roi.ExpandToOneRingNeighbours();
remesh_roi.LocalOptimize(true, true);
int[] new_roi = remesh_roi.ToArray();
// get rid of extrude group
FaceGroupUtil.SetGroupToGroup(Mesh, extrude_group, 0);
/* clean up via remesh
* - constrain loop we filled to itself
*/
RegionRemesher r = new RegionRemesher(Mesh, new_roi);
DCurve3 top_curve = MeshUtil.ExtractLoopV(Mesh, extrude.NewLoop.Vertices);
DCurveProjectionTarget curve_target = new DCurveProjectionTarget(top_curve);
int[] top_loop = (int[])extrude.NewLoop.Vertices.Clone();
r.Region.MapVerticesToSubmesh(top_loop);
MeshConstraintUtil.ConstrainVtxLoopTo(r.Constraints, r.Mesh, top_loop, curve_target);
DMeshAABBTree3 spatial = new DMeshAABBTree3(Mesh);
spatial.Build();
MeshProjectionTarget target = new MeshProjectionTarget(Mesh, spatial);
r.SetProjectionTarget(target);
bool bRemesh = true;
if (bRemesh)
{
r.Precompute();
r.EnableFlips = r.EnableSplits = r.EnableCollapses = true;
r.MinEdgeLength = target_edge_len;
r.MaxEdgeLength = 2 * target_edge_len;
r.EnableSmoothing = true;
r.SmoothSpeedT = 1.0f;
for (int k = 0; k < 40; ++k)
{
r.BasicRemeshPass();
}
r.SetProjectionTarget(null);
r.SmoothSpeedT = 0.25f;
for (int k = 0; k < 10; ++k)
{
r.BasicRemeshPass();
}
Debug.Assert(Mesh.CheckValidity());
r.BackPropropagate();
}
// smooth around the join region to clean up ugliness
smooth_region(Mesh, r.Region.BaseBorderV, 3);
}