// 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();
}
// 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));
}
// 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 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()
