public void CDS_FindClosestPointOnSurface()
{
ObjectId surfaceId = promptForTinSurface();
if (surfaceId.IsNull)
{
write("\nNo TIN Surface selected.");
return;
}
PromptPointResult result = _editor.GetPoint(
"\nSelect point outside surface: ");
if (result.Status != PromptStatus.OK)
{
write("\nNo point selected.");
return;
}
Point3d selectedPoint = result.Value;
Point3d closestPointFound = Point3d.Origin;
double shortestDistanceSoFar = Double.MaxValue;
using (Transaction tr = startTransaction())
{
TinSurface surface = surfaceId.GetObject(OpenMode.ForRead)
as TinSurface;
write("\nSelected surface: " + surface.Name);
write("\nSelected point: " + selectedPoint.ToString());
ObjectIdCollection borders = surface.ExtractBorder(
SurfaceExtractionSettingsType.Model);
foreach (ObjectId borderId in borders)
{
Polyline3d border = borderId.GetObject(OpenMode.ForRead)
as Polyline3d;
Point3d closestToBorder =
border.GetClosestPointTo(selectedPoint, false);
double distance = selectedPoint.DistanceTo(closestToBorder);
if (distance < shortestDistanceSoFar)
{
closestPointFound = closestToBorder;
shortestDistanceSoFar = distance;
}
}
}
write("\nClosest point found: " + closestPointFound.ToString());
using (Transaction tr = startTransaction())
{
BlockTableRecord btr = tr.GetObject(_database.CurrentSpaceId,
OpenMode.ForWrite) as BlockTableRecord;
Line line = new Line(selectedPoint, closestPointFound);
btr.AppendEntity(line);
tr.AddNewlyCreatedDBObject(line, true);
tr.Commit();
}
}
public static Point3d FindClosestPoint(Transaction trans, ObjectId idA, ObjectId idB)
{
Polyline3d curveA = trans.GetObject(idA, OpenMode.ForRead) as Polyline3d;
Polyline3d curveB = trans.GetObject(idB, OpenMode.ForRead) as Polyline3d;
double distance = double.MaxValue;
Point3d result = Point3d.Origin;
for (double param = curveA.StartParam; param < curveA.EndParam; param += ((curveA.EndParam - curveA.StartParam) / 100))
{
Point3d pointOnA = curveA.GetPointAtParameter(param);
Point3d closestPointOnB = curveB.GetClosestPointTo(pointOnA, false);
double distanceBetweenPoints = pointOnA.DistanceTo(closestPointOnB);
if (distanceBetweenPoints < distance)
{
distance = distanceBetweenPoints;
result = pointOnA; // equals closestPointOnB
}
}
return(result);
}
///<summary>
/// Get the intersection points between this planar entity and a curve.
///</summary>
///<param name="cur">The curve to check intersections against.</param>
///<returns>An array of Point3d intersections.</returns>
public static Point3d IntersectWith(Point3d pt, Vector3d vect, Polyline3d poly0, Polyline3d poly, double testWidth, Document doc)
{
Database db = doc.Database;
using (Transaction tr = db.TransactionManager.StartTransaction())
{
BlockTable bt = (BlockTable)tr.GetObject(db.BlockTableId, OpenMode.ForRead, false);
BlockTableRecord btr = (BlockTableRecord)tr.GetObject(bt[BlockTableRecord.ModelSpace], OpenMode.ForWrite, false);
string layerName = CreateAndAssignALayer(Setting.defaultLayerName);//incase if this layer not exist
if (layerName == string.Empty)
{
layerName = "0";
}
#region create a 2d line on XY plane in order to find the intersect point for on TBM centerline
//create a 2d point
Point3d pt0 = new Point3d(pt.X, pt.Y, 0);
Vector3d v = vect.GetNormal() * testWidth;
Matrix3d mat = Matrix3d.Displacement(v);
Point3d npt = pt0.TransformBy(mat);
v = vect.GetNormal() * -testWidth;
mat = Matrix3d.Displacement(v);
Point3d npt1 = pt0.TransformBy(mat);
//create a 2d line in XY plane and add to drawing, this use to intersect with TBM alignment, so I can find the point in TBM alignment to create circle
Line ln = new Line(npt, npt1);
ln.Layer = layerName;
btr.AppendEntity(ln);
tr.AddNewlyCreatedDBObject(ln, true);
//get the alignment object and find the nearest point to the nominated point
Point3dCollection pts3D = new Point3dCollection();
Point3d pt_intersect_in_TBM = Point3d.Origin;
try
{
poly0.IntersectWith(ln, Intersect.OnBothOperands, pts3D, IntPtr.Zero, IntPtr.Zero);
if (pts3D.Count > 0)
{
Point3d p = pts3D[0];
DBPoint db_pt = new DBPoint(p);
db_pt.Layer = layerName;
btr.AppendEntity(db_pt);
tr.AddNewlyCreatedDBObject(db_pt, true);
try
{
double para = poly0.GetParameterAtPoint(pts3D[0]);//this is where it will fail, don't know why!
//ed.WriteMessage($"{pts3D[0]}, {para}\n");
pt_intersect_in_TBM = poly.GetPointAtParameter(para);
return(pt_intersect_in_TBM);
}
catch
{
pt_intersect_in_TBM = poly.GetClosestPointTo(p, Vector3d.ZAxis, true);//when GetParameterAtPoint fail, this is should work. but use in caution!
}
}
#endregion
}
catch { }
tr.Commit();
return(pt_intersect_in_TBM);
}
}
