protected virtual DMesh3 BuildMesh_IdenticalWeld(STLSolid solid)
{
var builder = new DMesh3Builder();
builder.AppendNewMesh(false, false, false, false);
DVectorArray3f vertices = solid.Vertices;
int N = vertices.Count;
int[] mapV = new int[N];
var uniqueV = new Dictionary <Vector3f, int>();
for (int vi = 0; vi < N; ++vi)
{
Vector3f v = vertices[vi];
int existing_idx;
if (uniqueV.TryGetValue(v, out existing_idx))
{
mapV[vi] = existing_idx;
}
else
{
int vid = builder.AppendVertex(v.x, v.y, v.z);
uniqueV[v] = vid;
mapV[vi] = vid;
}
}
append_mapped_triangles(solid, builder, mapV);
return(builder.Meshes[0]);
}
protected virtual void BuildMesh_NoMerge(STLSolid solid, IMeshBuilder builder)
{
/*int meshID = */ builder.AppendNewMesh(false, false, false, false);
DVectorArray3f vertices = solid.Vertices;
int nTris = vertices.Count / 3;
for (int ti = 0; ti < nTris; ++ti)
{
Vector3f va = vertices[3 * ti];
int a = builder.AppendVertex(va.x, va.y, va.z);
Vector3f vb = vertices[3 * ti + 1];
int b = builder.AppendVertex(vb.x, vb.y, vb.z);
Vector3f vc = vertices[3 * ti + 2];
int c = builder.AppendVertex(vc.x, vc.y, vc.z);
builder.AppendTriangle(a, b, c);
}
}
protected virtual void BuildMesh_IdenticalWeld(STLSolid solid, IMeshBuilder builder)
{
/*int meshID = */ builder.AppendNewMesh(false, false, false, false);
DVectorArray3f vertices = solid.Vertices;
int N = vertices.Count;
int[] mapV = new int[N];
Dictionary <Vector3f, int> uniqueV = new Dictionary <Vector3f, int>();
for (int vi = 0; vi < N; ++vi)
{
Vector3f v = vertices[vi];
int existing_idx;
if (uniqueV.TryGetValue(v, out existing_idx))
{
mapV[vi] = existing_idx;
}
else
{
int vid = builder.AppendVertex(v.x, v.y, v.z);
uniqueV[v] = vid;
mapV[vi] = vid;
}
}
int nTris = N / 3;
for (int ti = 0; ti < nTris; ++ti)
{
int a = mapV[3 * ti];
int b = mapV[3 * ti + 1];
int c = mapV[3 * ti + 2];
if (a == b || a == c || b == c) // don't try to add degenerate triangles
{
continue;
}
builder.AppendTriangle(a, b, c);
}
}
protected virtual DMesh3 BuildMesh_TolerantWeld(STLSolid solid, double weld_tolerance)
{
var builder = new DMesh3Builder();
builder.AppendNewMesh(false, false, false, false);
DVectorArray3f vertices = solid.Vertices;
int N = vertices.Count;
int[] mapV = new int[N];
AxisAlignedBox3d bounds = AxisAlignedBox3d.Empty;
for (int i = 0; i < N; ++i)
{
bounds.Contain(vertices[i]);
}
// [RMS] because we are only searching within tiny radius, there is really no downside to
// using lots of bins here, except memory usage. If we don't, and the mesh has a ton of triangles
// very close together (happens all the time on big meshes!), then this step can start
// to take an *extremely* long time!
int num_bins = 256;
if (N > 100000)
{
num_bins = 512;
}
if (N > 1000000)
{
num_bins = 1024;
}
if (N > 2000000)
{
num_bins = 2048;
}
if (N > 5000000)
{
num_bins = 4096;
}
var uniqueV = new PointHashGrid3d <int>(bounds.MaxDim / (float)num_bins, -1);
var pos = new Vector3f[N];
for (int vi = 0; vi < N; ++vi)
{
Vector3f v = vertices[vi];
var pair = uniqueV.FindNearestInRadius(v, weld_tolerance, (vid) =>
{
return(v.Distance(pos[vid]));
});
if (pair.Key == -1)
{
int vid = builder.AppendVertex(v.x, v.y, v.z);
uniqueV.InsertPoint(vid, v);
mapV[vi] = vid;
pos[vid] = v;
}
else
{
mapV[vi] = pair.Key;
}
}
append_mapped_triangles(solid, builder, mapV);
return(builder.Meshes[0]);
}