// 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(NGonsCore.geometry3Sharp.mesh.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();
}
// 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(NGonsCore.geometry3Sharp.mesh.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(NGonsCore.geometry3Sharp.mesh.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();
}
protected void do_flatten(DMesh3 mesh)
{
double BAND_HEIGHT = flatten_band_height;
Vector3d down_axis = -Vector3d.AxisY;
double dot_thresh = 0.2;
AxisAlignedBox3d bounds = mesh.CachedBounds;
DMeshAABBTree3 spatial = new DMeshAABBTree3(mesh, true);
Ray3d ray = new Ray3d(bounds.Center - 2 * bounds.Height * Vector3d.AxisY, Vector3d.AxisY);
int hit_tid = spatial.FindNearestHitTriangle(ray);
Frame3f hitF;
MeshQueries.RayHitPointFrame(mesh, spatial, ray, out hitF);
Vector3d basePt = hitF.Origin;
Frame3f basePlane = new Frame3f(basePt, Vector3f.AxisY);
MeshConnectedComponents components = new MeshConnectedComponents(mesh)
{
FilterF = (tid) => {
if (mesh.GetTriangleGroup(tid) != LastExtrudeOuterGroupID)
{
return(false);
}
Vector3d n, c; double a;
mesh.GetTriInfo(tid, out n, out a, out c);
double h = Math.Abs(c.y - basePt.y);
if (h > BAND_HEIGHT)
{
return(false);
}
if (n.Dot(down_axis) < dot_thresh)
{
return(false);
}
return(true);
},
SeedFilterF = (tid) => {
return(tid == hit_tid);
}
};
components.FindConnectedT();
MeshFaceSelection all_faces = new MeshFaceSelection(mesh);
foreach (var comp in components)
{
MeshVertexSelection vertices = new MeshVertexSelection(mesh);
vertices.SelectTriangleVertices(comp.Indices);
foreach (int vid in vertices)
{
Vector3d v = mesh.GetVertex(vid);
v = basePlane.ProjectToPlane((Vector3f)v, 2);
mesh.SetVertex(vid, v);
}
all_faces.SelectVertexOneRings(vertices);
}
all_faces.ExpandToOneRingNeighbours(3, (tid) => {
return(mesh.GetTriangleGroup(tid) == LastExtrudeOuterGroupID);
});
RegionRemesher r = new RegionRemesher(mesh, all_faces);
r.SetProjectionTarget(MeshProjectionTarget.Auto(mesh));
r.SetTargetEdgeLength(2.0f);
r.SmoothSpeedT = 1.0f;
for (int k = 0; k < 10; ++k)
{
r.BasicRemeshPass();
}
r.SetProjectionTarget(null);
r.SmoothSpeedT = 1.0f;
for (int k = 0; k < 10; ++k)
{
r.BasicRemeshPass();
}
r.BackPropropagate();
}