/// <summary>
/// count 6-nbrs of each voxel, discard if count <= minNbrs
/// </summary>
public void Filter(int nMinNbrs)
{
AxisAlignedBox3i bounds = GridBounds;
bounds.Max -= Vector3i.One;
for (int i = 0; i < Bits.Length; ++i)
{
if (Bits[i] == false)
{
continue;
}
Vector3i idx = ToIndex(i);
int nc = 0;
for (int k = 0; k < 6 && nc <= nMinNbrs; ++k)
{
Vector3i nbr = idx + gIndices.GridOffsets6[k];
if (bounds.Contains(nbr) == false)
{
continue;
}
if (Get(nbr))
{
nc++;
}
}
if (nc <= nMinNbrs)
{
Bits[i] = false;
}
}
}
public void Generate()
{
append_mesh();
AxisAlignedBox3i bounds = Voxels.GridBounds;
bounds.Max -= Vector3i.One;
int[] vertices = new int[4];
foreach (Vector3i nz in Voxels.NonZeros())
{
check_counts_or_append(6, 2);
Box3d cube = Box3d.UnitZeroCentered;
cube.Center = (Vector3d)nz;
for (int fi = 0; fi < 6; ++fi)
{
// checks dependent on neighbours
Index3i nbr = nz + gIndices.GridOffsets6[fi];
if (bounds.Contains(nbr))
{
if (SkipInteriorFaces && Voxels.Get(nbr))
{
continue;
}
}
else if (CapAtBoundary == false)
{
continue;
}
int ni = gIndices.BoxFaceNormals[fi];
Vector3f n = (Vector3f)(Math.Sign(ni) * cube.Axis(Math.Abs(ni) - 1));
NewVertexInfo vi = new NewVertexInfo(Vector3d.Zero, n);
if (ColorSourceF != null)
{
vi.c = ColorSourceF(nz);
vi.bHaveC = true;
}
for (int j = 0; j < 4; ++j)
{
vi.v = cube.Corner(gIndices.BoxFaces[fi, j]);
vertices[j] = cur_mesh.AppendVertex(vi);
}
Index3i t0 = new Index3i(vertices[0], vertices[1], vertices[2], Clockwise);
Index3i t1 = new Index3i(vertices[0], vertices[2], vertices[3], Clockwise);
cur_mesh.AppendTriangle(t0);
cur_mesh.AppendTriangle(t1);
}
}
}