public static Plane3D?GetPlane(IList <Point3D> polygon)
{
int count = polygon.Count;
if (count < 3)
{
return(new Plane3D?());
}
Point3D point = polygon[0];
Vector3D u = polygon[1] - point;
for (int index = 2; index < count; ++index)
{
Vector3D v = polygon[index] - point;
Vector3D vector3D = Vector3D.CrossProduct(u, v);
if (!Vector3D.AreApproxEqual(vector3D, Vector3D.Zero))
{
vector3D.Normalize();
return(new Plane3D?(new Plane3D(vector3D, point)));
}
}
return(new Plane3D?());
}
protected override WW.Math.Point3D ProcessWcsPosition(
InteractionContext context,
WW.Math.Point3D p)
{
p = base.ProcessWcsPosition(context, p);
p = DxfLine.CreateInteractor.SnapHorizontalOrVertical((DxfEntity.Interactor) this, p, context, this.ControlPointIndexAtFirstMouseDown);
if (this.ClickCount > 0 && this.nullable_1.HasValue)
{
DxfLine entity = (DxfLine)this.Entity;
if (this.ControlPointIndexAtFirstMouseDown == 0)
{
Vector3D u = entity.point3D_1 - p;
if (Vector3D.AreApproxEqual(u, Vector3D.Zero))
{
u = entity.point3D_1 - entity.point3D_0;
}
if (!Vector3D.AreApproxEqual(u, Vector3D.Zero))
{
p = entity.point3D_1 - this.nullable_1.Value * u.GetUnit();
}
}
else
{
Vector3D u = p - entity.point3D_0;
if (Vector3D.AreApproxEqual(u, Vector3D.Zero))
{
u = entity.point3D_1 - entity.point3D_0;
}
if (!Vector3D.AreApproxEqual(u, Vector3D.Zero))
{
p = entity.point3D_0 + this.nullable_1.Value * u.GetUnit();
}
}
}
return(p);
}
