public static void ConvexHull(ref Surface surf)
{
if (surf.NumPoints < 4)
return;
//add the middle point to make a tetrahedron for some numerical stability
Point3D Middle = new Point3D();
for (int i = 0; i < surf.NumPoints; i++)
{
Middle += surf.Point(i);
}
Middle /= surf.NumPoints;
int mid = surf.AddPoint(Middle);
//clean out the faces, and add faces of a tetrahedron using the first 3 pts and the middle.
Point3D inside = (surf.Point(0) + surf.Point(1) + surf.Point(2) + surf.Point(mid)) / 4.0;
while (surf.NumFaces > 0)
surf.RemoveFace(0);
surf.AddFace(0, 1, 2, inside);
surf.AddFace(0, 1, mid, inside);
surf.AddFace(0, 2, mid, inside);
surf.AddFace(1, 2, mid, inside);
// add in points one at a time, remove and replace faces as necessary
for (int i = 3; i < surf.NumPoints; i++)
{
List<Edge> Edges = new List<Edge>();
//for the ith point...
//go through the each existing face,
for (int j = surf.NumFaces - 1; j >= 0; j--)
{
//if a triangle is facing our new point, remove the face, add its edges to a list.
double tmp = Point3D.Dot(surf.FaceNormal(j), surf.Point(i) - surf.Point(surf.Face(j).I));
if (Point3D.Dot(surf.FaceNormal(j), (surf.Point(i) - surf.Point(surf.Face(j).I)).Normalized) > -DMS.EPSILON)
{
Edges.Add(new Edge(surf.Face(j).I, surf.Face(j).J));
Edges.Add(new Edge(surf.Face(j).J, surf.Face(j).K));
Edges.Add(new Edge(surf.Face(j).K, surf.Face(j).I));
surf.RemoveFace(j);
}
}
//now add a triangle using any non duplicated edges together with our new point.
Edges.Sort(Edge.Comparison);
for (int j = 0; j < Edges.Count(); j++)
{
if (j != Edges.Count() - 1 && Edges[j] == Edges[j + 1])
{
//this edge is a duplicate, do nothing.
j++; //we'll skip the next one which is a duplicate too.
continue;
}
surf.AddFace(Edges[j].I, Edges[j].J, i, inside);
}
}
}
static void Main(string[] args)
{
#if false //test code
StreamWriter testsw = new StreamWriter("D:\\PersonalProjects\\Bridges 2011\\artshow\\sphere.stl");
testsw.WriteLine("solid sphereshell");
new Sphere(36.128, 5, true).Output(testsw, 1.0);
//Torus(5, 1.5, 3).Output(testsw, 1.0);
testsw.WriteLine("endsolid");
testsw.Close();
return;
#endif
ModelType model = ModelType.Outside;
if (args.Count() > 1)
{
try { model = (ModelType)(Int16.Parse(args[1])); }
catch { model = ModelType.Outside; }
}
double dRadius = 50.0;
double dHalfLineWidth = 0.5;
double dHalfLineHeight = 0.4;
if (model == ModelType.Empty)
{
dHalfLineWidth = 0.5;
dHalfLineHeight = 1.0;
dRadius = 36.128 + dHalfLineHeight; //inside shell is a little smaller than white plastic ball
}
string Filename = args[0];
if (model == ModelType.Empty)
Filename += "_empty.stl";
else if (model == ModelType.Inside)
Filename += "_glow.stl";
else if (model == ModelType.Outside)
Filename += ".stl";
StreamWriter sw = new StreamWriter(Filename);
if (model == ModelType.Inside || model == ModelType.Outside)
{
sw.WriteLine("solid sphereshell");
Surface SphereSurface = new Surface();
if (model == ModelType.Inside)
{
SphereSurface.AddSurface(new Sphere(dRadius + dHalfLineHeight + 1.95, 6, true));
SphereSurface.AddSurface(new Sphere(dRadius + dHalfLineHeight - 0.05, 4, false));
}
else if (model == ModelType.Outside)
{
SphereSurface.AddSurface(new Sphere(dRadius - dHalfLineHeight - 1.95, 4, true));
SphereSurface.AddSurface(new Sphere(dRadius - dHalfLineHeight + 0.05, 6, false));
}
Point3D HolePunch = new Point3D(0, -1, 0).ScaledTo(dRadius);
SurfaceTools.PunchHole(ref SphereSurface, //surf
HolePunch, //center
HolePunch, //direction
10, //length
1.2); //radius
SphereSurface.Output(sw, 1.0);
sw.WriteLine("endsolid");
}
sw.WriteLine("solid tour");
Tour newTour = new Tour(args[0] + ".csv", dRadius, dHalfLineWidth, dHalfLineHeight);
Surface TourSurface = new Surface();
TourSurface.AddSurface(newTour);
TourSurface.Output(sw, 1.0);
sw.WriteLine("endsolid");
sw.Close();
}
public static void PunchHole(ref Surface surf, Point3D center, Point3D direction, double Length, double Radius)
{
Surface HoleWall = new Surface();
List<int> HoleIdxs = new List<int>();
Point3D dir = direction.Normalized;
for (int i = 0; i < surf.NumPoints; i++)
{
if (!IsInCylinder(surf.Point(i), center, dir, Length, Radius))
continue;
for (int j = surf.NumFaces - 1; j >= 0; j--)
{
if (surf.Face(j).I == i ||
surf.Face(j).J == i ||
surf.Face(j).K == i)
{
if (!IsInCylinder(surf.Point(surf.Face(j).I), center, dir, Length, Radius)) HoleIdxs.Add(surf.Face(j).I);
if (!IsInCylinder(surf.Point(surf.Face(j).J), center, dir, Length, Radius)) HoleIdxs.Add(surf.Face(j).J);
if (!IsInCylinder(surf.Point(surf.Face(j).K), center, dir, Length, Radius)) HoleIdxs.Add(surf.Face(j).K);
surf.RemoveFace(j);
}
}
}
//make sure points in hole wall are unique
for (int j = HoleIdxs.Count() - 1; j >= 0; j--)
{
Point3D NewPt = surf.Point(HoleIdxs[j]);
//check that existing points in HoleWall surface don't match
int k;
for (k = 0; k < HoleWall.NumPoints; k++)
{
if (NewPt == HoleWall.Point(k))
break;
}
//add if we haven't found it.
if (k == HoleWall.NumPoints)
HoleWall.AddPoint(NewPt);
}
//get the convex hull faces, then either remove them if they're pointing in our direction, or reverse them
ConvexHull(ref HoleWall);
for (int i = HoleWall.NumFaces - 1; i >= 0; i--)
{
double IR = HoleWall.Point(HoleWall.Face(i).I).R;
double JR = HoleWall.Point(HoleWall.Face(i).J).R;
double KR = HoleWall.Point(HoleWall.Face(i).K).R;
if ( IR > center.R && JR > center.R && KR > center.R ||
IR < center.R && JR < center.R && KR < center.R )
{
HoleWall.RemoveFace(i);
}
else
{
HoleWall.Face(i).Reverse();
}
}
//add in the new hole wall
surf.AddSurface(HoleWall);
}
public void AddSurface(Surface s2)
{
int nFaces = mFaces.Count;
int nPoints = mPts.Count;
mFaces.AddRange(s2.mFaces);
mPts.AddRange(s2.mPts);
for (int i = nFaces; i < mFaces.Count; i++)
{
mFaces[i].Offset(nPoints);
}
}
