void generate_support(Vector3f origin, float dx,
int ni, int nj, int nk,
DenseGrid3f supportGrid)
{
supportGrid.resize(ni, nj, nk);
supportGrid.assign(1); // sentinel
if (DebugPrint) System.Console.WriteLine("start");
bool CHECKERBOARD = false;
System.Console.WriteLine("Computing SDF");
// compute unsigned SDF
MeshSignedDistanceGrid sdf = new MeshSignedDistanceGrid(Mesh, CellSize) {
ComputeSigns = true, ExactBandWidth = 3,
/*,ComputeMode = MeshSignedDistanceGrid.ComputeModes.FullGrid*/ };
sdf.CancelF = Cancelled;
sdf.Compute();
if (Cancelled())
return;
var distanceField = new DenseGridTrilinearImplicit(sdf.Grid, sdf.GridOrigin, sdf.CellSize);
double angle = MathUtil.Clamp(OverhangAngleDeg, 0.01, 89.99);
double cos_thresh = Math.Cos(angle * MathUtil.Deg2Rad);
System.Console.WriteLine("Marking overhangs");
// Compute narrow-band distances. For each triangle, we find its grid-coord-bbox,
// and compute exact distances within that box. The intersection_count grid
// is also filled in this computation
double ddx = (double)dx;
double ox = (double)origin[0], oy = (double)origin[1], oz = (double)origin[2];
Vector3d va = Vector3d.Zero, vb = Vector3d.Zero, vc = Vector3d.Zero;
foreach (int tid in Mesh.TriangleIndices()) {
if (tid % 100 == 0 && Cancelled())
break;
Mesh.GetTriVertices(tid, ref va, ref vb, ref vc);
Vector3d normal = MathUtil.Normal(ref va, ref vb, ref vc);
if (normal.Dot(-Vector3d.AxisY) < cos_thresh)
continue;
// real ijk coordinates of va/vb/vc
double fip = (va[0] - ox) / ddx, fjp = (va[1] - oy) / ddx, fkp = (va[2] - oz) / ddx;
double fiq = (vb[0] - ox) / ddx, fjq = (vb[1] - oy) / ddx, fkq = (vb[2] - oz) / ddx;
double fir = (vc[0] - ox) / ddx, fjr = (vc[1] - oy) / ddx, fkr = (vc[2] - oz) / ddx;
// clamped integer bounding box of triangle plus exact-band
int exact_band = 0;
int i0 = MathUtil.Clamp(((int)MathUtil.Min(fip, fiq, fir)) - exact_band, 0, ni - 1);
int i1 = MathUtil.Clamp(((int)MathUtil.Max(fip, fiq, fir)) + exact_band + 1, 0, ni - 1);
int j0 = MathUtil.Clamp(((int)MathUtil.Min(fjp, fjq, fjr)) - exact_band, 0, nj - 1);
int j1 = MathUtil.Clamp(((int)MathUtil.Max(fjp, fjq, fjr)) + exact_band + 1, 0, nj - 1);
int k0 = MathUtil.Clamp(((int)MathUtil.Min(fkp, fkq, fkr)) - exact_band, 0, nk - 1);
int k1 = MathUtil.Clamp(((int)MathUtil.Max(fkp, fkq, fkr)) + exact_band + 1, 0, nk - 1);
// don't put into y=0 plane
if (j0 == 0)
j0 = 1;
// compute distance for each tri inside this bounding box
// note: this can be very conservative if the triangle is large and on diagonal to grid axes
for (int k = k0; k <= k1; ++k) {
for (int j = j0; j <= j1; ++j) {
for (int i = i0; i <= i1; ++i) {
Vector3d gx = new Vector3d((float)i * dx + origin[0], (float)j * dx + origin[1], (float)k * dx + origin[2]);
float d = (float)MeshSignedDistanceGrid.point_triangle_distance(ref gx, ref va, ref vb, ref vc);
// vertical checkerboard pattern (eg 'tips')
if (CHECKERBOARD) {
int zz = (k % 2 == 0) ? 1 : 0;
if (i % 2 == zz)
continue;
}
if (d < dx / 2) {
if (j > 1) {
supportGrid[i, j, k] = SUPPORT_TIP_TOP;
supportGrid[i, j - 1, k] = SUPPORT_TIP_BASE;
} else {
supportGrid[i, j, k] = SUPPORT_TIP_BASE;
}
}
}
}
}
}
if (Cancelled())
return;
//process_version1(supportGrid, distanceField);
//process_version2(supportGrid, distanceField);
generate_graph(supportGrid, distanceField);
//Util.WriteDebugMesh(MakeDebugGraphMesh(), "c:\\scratch\\__LAST_GRAPH_INIT.obj");
postprocess_graph();
//Util.WriteDebugMesh(MakeDebugGraphMesh(), "c:\\scratch\\__LAST_GRAPH_OPT.obj");
}
public DenseGridTrilinearImplicit(MeshSignedDistanceGrid sdf_grid)
{
Grid = sdf_grid.Grid;
GridOrigin = sdf_grid.GridOrigin;
CellSize = sdf_grid.CellSize;
}
void generate_support(Vector3f origin, float dx,
int ni, int nj, int nk,
DenseGrid3f supportGrid)
{
supportGrid.resize(ni, nj, nk);
supportGrid.assign(1); // sentinel
bool CHECKERBOARD = false;
// compute unsigned SDF
int exact_band = 1;
if (SubtractMesh && SubtractMeshOffset > 0)
{
int offset_band = (int)(SubtractMeshOffset / CellSize) + 1;
exact_band = Math.Max(exact_band, offset_band);
}
sdf = new MeshSignedDistanceGrid(Mesh, CellSize)
{
ComputeSigns = true, ExactBandWidth = exact_band
};
sdf.CancelF = this.CancelF;
sdf.Compute();
if (CancelF())
{
return;
}
var distanceField = new DenseGridTrilinearImplicit(sdf.Grid, sdf.GridOrigin, sdf.CellSize);
double angle = MathUtil.Clamp(OverhangAngleDeg, 0.01, 89.99);
double cos_thresh = Math.Cos(angle * MathUtil.Deg2Rad);
// Compute narrow-band distances. For each triangle, we find its grid-coord-bbox,
// and compute exact distances within that box. The intersection_count grid
// is also filled in this computation
double ddx = (double)dx;
double ox = (double)origin[0], oy = (double)origin[1], oz = (double)origin[2];
Vector3d va = Vector3d.Zero, vb = Vector3d.Zero, vc = Vector3d.Zero;
foreach (int tid in Mesh.TriangleIndices())
{
if (tid % 100 == 0 && CancelF())
{
break;
}
Mesh.GetTriVertices(tid, ref va, ref vb, ref vc);
Vector3d normal = MathUtil.Normal(ref va, ref vb, ref vc);
if (normal.Dot(-Vector3d.AxisY) < cos_thresh)
{
continue;
}
// real ijk coordinates of va/vb/vc
double fip = (va[0] - ox) / ddx, fjp = (va[1] - oy) / ddx, fkp = (va[2] - oz) / ddx;
double fiq = (vb[0] - ox) / ddx, fjq = (vb[1] - oy) / ddx, fkq = (vb[2] - oz) / ddx;
double fir = (vc[0] - ox) / ddx, fjr = (vc[1] - oy) / ddx, fkr = (vc[2] - oz) / ddx;
// clamped integer bounding box of triangle plus exact-band
int extra_band = 0;
int i0 = MathUtil.Clamp(((int)MathUtil.Min(fip, fiq, fir)) - extra_band, 0, ni - 1);
int i1 = MathUtil.Clamp(((int)MathUtil.Max(fip, fiq, fir)) + extra_band + 1, 0, ni - 1);
int j0 = MathUtil.Clamp(((int)MathUtil.Min(fjp, fjq, fjr)) - extra_band, 0, nj - 1);
int j1 = MathUtil.Clamp(((int)MathUtil.Max(fjp, fjq, fjr)) + extra_band + 1, 0, nj - 1);
int k0 = MathUtil.Clamp(((int)MathUtil.Min(fkp, fkq, fkr)) - extra_band, 0, nk - 1);
int k1 = MathUtil.Clamp(((int)MathUtil.Max(fkp, fkq, fkr)) + extra_band + 1, 0, nk - 1);
// don't put into y=0 plane
//if (j0 == 0)
// j0 = 1;
// compute distance for each tri inside this bounding box
// note: this can be very conservative if the triangle is large and on diagonal to grid axes
for (int k = k0; k <= k1; ++k)
{
for (int j = j0; j <= j1; ++j)
{
for (int i = i0; i <= i1; ++i)
{
Vector3d gx = new Vector3d((float)i * dx + origin[0], (float)j * dx + origin[1], (float)k * dx + origin[2]);
float d = (float)MeshSignedDistanceGrid.point_triangle_distance(ref gx, ref va, ref vb, ref vc);
// vertical checkerboard pattern (eg 'tips')
if (CHECKERBOARD)
{
int zz = (k % 2 == 0) ? 1 : 0;
if (i % 2 == zz)
{
continue;
}
}
if (d < dx / 2)
{
supportGrid[i, j, k] = SUPPORT_TIP_TOP;
}
}
}
}
}
if (CancelF())
{
return;
}
fill_vertical_spans(supportGrid, distanceField);
generate_mesh(supportGrid, distanceField);
}