public void ComputeBoundQuad()
{
MyVector3 normal = Normal();
MyVector3 xaxis = new MyVector3(1, 0, 0);
MyVector3 yaxis = new MyVector3(0, 1, 0);
MyVector3 zaxis = new MyVector3(0, 0, 1);
MyVector3 rotAxis = zaxis.Cross(normal).Normalize();
double cos = zaxis.Dot(normal);
if (cos > 1)
{
cos = 1;
}
if (cos < -1)
{
cos = -1;
}
double rotAngle = Math.Acos(cos);
MyMatrix4d R = MyMatrix4d.RotationMatrix(rotAxis, rotAngle);
MyVector3 new_xaxis = (R * new MyVector4(xaxis)).XYZ().Normalize();
MyVector3 new_yaxis = (R * new MyVector4(yaxis)).XYZ().Normalize();
CoordinateFrame frame = new CoordinateFrame(this.planeCenter, new_xaxis, new_yaxis, normal);
double xmin = double.MaxValue; double ymin = double.MaxValue;
double xmax = double.MinValue; double ymax = double.MinValue;
foreach (MyVector3 v in this.planeVertices)
{
MyVector3 u = frame.GetPointLocalCoord(v);
xmin = Math.Min(u.x, xmin);
xmax = Math.Max(u.x, xmax);
ymin = Math.Min(u.y, ymin);
ymax = Math.Max(u.y, ymax);
}
MyVector3 v1 = new MyVector3(xmin, ymin, 0);
MyVector3 v2 = new MyVector3(xmax, ymin, 0);
MyVector3 v3 = new MyVector3(xmax, ymax, 0);
MyVector3 v4 = new MyVector3(xmin, ymax, 0);
SmartCanvas.Point3[] pts3 =
new SmartCanvas.Point3[4] {
new SmartCanvas.Point3(frame.GetPointSpaceCoord(v1)),
new SmartCanvas.Point3(frame.GetPointSpaceCoord(v2)),
new SmartCanvas.Point3(frame.GetPointSpaceCoord(v3)),
new SmartCanvas.Point3(frame.GetPointSpaceCoord(v4))
};
this.boundQuad = new Quad3D(pts3);
}
public void FindBoundPolygon()
{
// find convexhull
PointF[] ps = new PointF[this.slicePoints2d.Count];
for (int i = 0; i < this.slicePoints2d.Count; i++)
{
PointF p = new PointF((float)this.slicePoints2d[i].x, (float)this.slicePoints2d[i].y);
ps[i] = p;
}
PointF[] hull = CvInvoke.ConvexHull(ps);
// find boundary polygon
VectorOfPointF hull2 = new VectorOfPointF();
hull2.Push(hull);
VectorOfPointF poly = new VectorOfPointF();
// when inferring # of polygon edge, the 3-rd param can be [0.0005,0.0015], than choose the best(how to define "best"??)
CvInvoke.ApproxPolyDP(hull2, poly, 0.0003, true);
for (int i = 0; i < poly.Size; i++)
{
this.cornerPoints2d.Add(new MyVector2(poly[i].X, poly[i].Y));
}
// unproject to 3d
foreach (MyVector2 corner2d in this.cornerPoints2d)
{
MyVector3 corner3d = frame.GetPointSpaceCoord(new MyVector3(corner2d, 0.0));
this.cornerPoints3d.Add(corner3d);
}
}
