Vb.net Select PL AND a point

[Jozi68]

I am using the code below to get a user to select a polyline. This is working beautifully. But now I also need the point where the user clicked on the Polyline, i.e. the X and Y coordinates.
Any Ideas?

Dim myPEO AsNew Autodesk.AutoCAD.EditorInput.PromptEntityOptions(v bLf & "Select a Polyline:")
myDWG = Autodesk.AutoCAD.ApplicationServices.Application.D ocumentManager.MdiActiveDocument
myDB = myDWG.Database
myEd = myDWG.Editor
myPEO.SetRejectMessage("You must select a PolyLine." & vbCrLf)
myPEO.AddAllowedClass(GetType(Autodesk.AutoCAD.DatabaseServices.Polyline), False)
myPER = myEd.GetEntity(myPEO)
myPS = myPER.Status
SelectCase myPS
Case Autodesk.AutoCAD.EditorInput.PromptStatus.OK
'MsgBox("Good job!")
myTransMan = myDWG.TransactionManager
myTrans = myTransMan.StartTransaction
myEnt = myPER.ObjectId.GetObject (Autodesk.AutoCAD.DatabaseServices.OpenMode.ForRea d)
'MsgBox("Entity is on layer " & myEnt.Layer)
'Where did he click?!
Case Autodesk.AutoCAD.EditorInput.PromptStatus.Cancel
'MsgBox("You cancelled.")
ExitSub
Case Autodesk.AutoCAD.EditorInput.PromptStatus.Error
MsgBox("Error warning.")
ExitSub
CaseElse
ExitSub
EndSelect

[SEANT]

Look at:

Autodesk.AutoCAD.EditorInput.PickPointSelectedObject

If you set the SelectedObject returned by myPER to an instance of that class then the selection point should be available from the PickPointDescriptor of the

PickPointSelectedObject.PickPoint

I’m not in a position to give that a test run, unfortunately. If the issue is still in question, I may have time this weekend.

[Jozi68]

Thanx Seant, could you please give more detail? I'm not sure how to implement this.

[SEANT]

It will have to wait till later as I'm about to head out the door. Sorry.

[gile]

Hi,

Here's a little sample (C#)

using System.Windows.Forms;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.EditorInput;
using Autodesk.AutoCAD.Geometry;
using Autodesk.AutoCAD.Runtime;
using acadApp = Autodesk.AutoCAD.ApplicationServices.Application;

namespace PickPoint
{
    public class Class1
    {
        [CommandMethod("Test")]
        public void Test()
        {
            Document doc = acadApp.DocumentManager.MdiActiveDocument;
            Database db = doc.Database;
            Editor ed = doc.Editor;
            PromptEntityOptions peo = new PromptEntityOptions("\nSelect a polyline: ");
            peo.SetRejectMessage("You must select a polyline\n");
            peo.AddAllowedClass(typeof(Polyline), false);
            PromptEntityResult per = ed.GetEntity(peo);
            if (per.Status == PromptStatus.OK)
            {
                using (Transaction tr = db.TransactionManager.StartTransaction())
                {
                    ObjectId id = per.ObjectId;
                    Point3d picked = per.PickedPoint;
                    Polyline pline = tr.GetObject(id, OpenMode.ForRead) as Polyline;
                    Point3d onPlinePt = pline.GetClosestPointTo(picked, ed.GetCurrentView().ViewDirection, false);
                    MessageBox.Show("Picked point: " + picked.ToString() +  "\nClosest point on polyline: " + onPlinePt.ToString());
                    tr.Commit();
                }
            }
        }
    }
}

A VB convertion (made with a .net code converter)

Imports System.Windows.Forms
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.EditorInput
Imports Autodesk.AutoCAD.Geometry
Imports Autodesk.AutoCAD.Runtime
Imports acadApp = Autodesk.AutoCAD.ApplicationServices.Application

Namespace PickPoint
    Public Class Class1
        <CommandMethod("Test")> _
        Public Sub Test()
            Dim doc As Document = acadApp.DocumentManager.MdiActiveDocument
            Dim db As Database = doc.Database
            Dim ed As Editor = doc.Editor
            Dim peo As New PromptEntityOptions(vbLf & "Select a polyline: ")
            peo.SetRejectMessage("You must select a polyline" & vbLf)
            peo.AddAllowedClass(GetType(Polyline), False)
            Dim per As PromptEntityResult = ed.GetEntity(peo)
            If per.Status = PromptStatus.OK Then
                Using tr As Transaction = db.TransactionManager.StartTransaction()
                    Dim id As ObjectId = per.ObjectId
                    Dim picked As Point3d = per.PickedPoint
                    Dim pline As Polyline = TryCast(tr.GetObject(id, OpenMode.ForRead), Polyline)                                        
                    Dim onPlinePt As Point3d = pline.GetClosestPointTo(picked, ed.GetCurrentView().ViewDirection, False)
                    MessageBox.Show(("Picked point: " & picked.ToString() & vbLf & "Closest point on polyline: ") + onPlinePt.ToString())
                    tr.Commit()
                End Using
            End If
        End Sub
    End Class
End Namespace

[SEANT]

Gile, that is a particularly concise and direct method which appears hard to beat.

I was hopeful that the Editor.GetSelection route would allow for additional filtering (if a person were interested in that sort of thing) but every attempt I’ve made to combine a SinglePick version of PromptEntityOptions along with SelectionFilters has crashed AutoCAD.

That would be a fairly useful option, so I’ll keep looking.

The example below works well enough but doesn’t bring anything new to the table.

Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.EditorInput
Imports Autodesk.AutoCAD.Geometry

Public Class STSCCommands
    <CommandMethod("Pop")> _
 Public Sub PointOnPoly()
        Dim db As Database = HostApplicationServices.WorkingDatabase
        Dim ed As Editor = Application.DocumentManager.MdiActiveDocument.Editor
        Dim pso As PromptSelectionOptions = New PromptSelectionOptions()
        pso.MessageForAdding = "Select a Poly: "
        pso.SinglePickInSpace = True
        pso.SingleOnly = True
        Dim result As PromptSelectionResult = ed.GetSelection(pso)
        If result.Status = PromptStatus.OK And result.Value.Count > 0 Then
            Using trn As Transaction = db.TransactionManager.StartTransaction
                Dim ppso As PickPointSelectedObject = DirectCast(result.Value(0), PickPointSelectedObject)
                Dim poly As Polyline = TryCast(trn.GetObject(result.Value(0).ObjectId, OpenMode.ForRead), Polyline)
                If poly IsNot Nothing Then
                    Dim p3d As Point3d = poly.GetClosestPointTo(ppso.PickPoint.PointOnLine, False)
                    ed.WriteMessage(p3d.ToString())
                End If
            End Using
        End If
    End Sub

[gile]

Seant,

To mimic the Editor.GetEntiy with Editor.GetSelection it seems to me it needs:
PromptSelectionOptions.SelectEverythingInAperture (rather than SinglePickInSpace)
and
PromptSelectionOptions.SingleOnly
as the LISP expression: (ssget "_:S:E")

Here's a C# example (works on A2007 and A2010)

        [CommandMethod("TEST")]
        public void test()
        {
            Document doc = acadApp.DocumentManager.MdiActiveDocument;
            Database db = doc.Database;
            Editor ed = doc.Editor;
            TypedValue[] filter = { new TypedValue(0, "LWPOLYLINE") };
            SelectionFilter selFilter = new SelectionFilter(filter);
            PromptSelectionOptions pso = new PromptSelectionOptions();
            pso.MessageForAdding = "Select a polyline: ";
            pso.SelectEverythingInAperture = true;
            pso.SingleOnly = true;
            PromptSelectionResult psr = ed.GetSelection(pso, selFilter);
            if (psr.Status == PromptStatus.OK)
            {
                using (Transaction tr = db.TransactionManager.StartTransaction())
                {
                    ObjectId[] ids = psr.Value.GetObjectIds();
                    ObjectId id = ids[0];
                    Polyline pline = tr.GetObject(id, OpenMode.ForRead) as Polyline;
                    PickPointSelectedObject ppso = psr.Value[0] as PickPointSelectedObject;
                    Point3d picked = ppso.PickPoint.PointOnLine;
                    Point3d onPlinePt = pline.GetClosestPointTo(picked, ed.GetCurrentView().ViewDirection, false);
                    MessageBox.Show("Picked point: " +
                        picked.ToString() +
                        "\nClosest point on polyline: " +
                        onPlinePt.ToString());
                    tr.Commit();
                }
            }
        }

[SEANT]

Gile, nicely done. The advanced filtering available from Editor.GetSelection makes that a compelling option in certain situations.

[gile]

Just a little thing for these routines to work whatever the current UCS and current view.

Using Editor.GetEntity,
the PickedPoint is UCS coordinates, so have to replace :

Point3d picked = per.PickedPoint;

by

Point3d picked = per.PickedPoint.TransformBy(ed.CurrentUserCoordinateSystem);

and the use :

Point3d onPlinePt = pline.GetClosestPointTo(picked, ed.GetCurrentView().ViewDirection, false);

Using Editor.GetSelection, it can be done this way:

PickPointSelectedObject ppso = psr.Value[0] as PickPointSelectedObject;
PickPointDescriptor ppd = ppso.PickPoint;
Point3d onPlinePt = pline.GetClosestPointTo(ppd.PointOnLine, ppd.Direction, false);

[SEANT]

Yes, I did notice that feature in Post #9, a critical feature in 3D work. It would have been processed at some point along the way. Yesterday, the amount of attention I could devote towards any aspect of the problem was focused primarily on filtering. Thanks again for the heads up.