For a single polyline entity of multiple segments, I'm looking to create a gap at each intersection. Ideally need to be able to specify the gap distance.

simple example:



more complex example:



Basic code outline:

1. Get polyline entity from editor
2. Explode polyline into individual polylines
3. test each polyline against each other for intersections (intersections must be 'genuine', eg. can't be between 2 consecutive segments)
4. create temporary circle at each intersection of specific radius
5. for each polyline, "trim" the contents inside the circle *(having difficulty at this point onwards)*, thereby removing the intersection
6. delete the temporary circles
7. for each existing polyline, where possible if they can be joined back up, do so

Biggest problem I'm facing is trimming each of the polylines at the circle intersections - I'm just not sure how to put this in code 

Eventually I would like to be able to incorporate arcs into the polylines.

My code so far (up to point 4):
 

        [CommandMethod("SelfIntersectPline")]

        public static void SelfIntersectPline()
        {
            Document doc = Application.DocumentManager.MdiActiveDocument;
            Database db = doc.Database;
            Editor ed = doc.Editor;
            PromptEntityOptions peo = new PromptEntityOptions(
                "\nSelect Curve: ");
            peo.SetRejectMessage("\nMust be a Curve...");

            PromptEntityResult per = ed.GetEntity(peo);
            if (per.Status != PromptStatus.OK) return;

            using (Transaction tr = db.TransactionManager.StartTransaction())
            {
                BlockTableRecord ms = tr.GetObject(db.CurrentSpaceId, OpenMode.ForWrite) as BlockTableRecord;

                //get curve and explode into entities, store curves in entities dbobjectcollection
                Curve curve = per.ObjectId.GetObject(OpenMode.ForRead) as Curve;
                DBObjectCollection origDBObjects = new DBObjectCollection();
                curve.Explode(origDBObjects);

                //erase original curve
                var originalCurve = (Entity)tr.GetObject(curve.ObjectId, OpenMode.ForWrite);
                originalCurve.Erase();

                //create temp dbcollection for circle entities
                DBObjectCollection circleDBObjects = new DBObjectCollection();

                //convert exploded curve entities to polylines
                for (int i = origDBObjects.Count - 1; i >= 0; i--)
                {
                    Curve curveObj = origDBObjects[i] as Curve;
                    origDBObjects.Add(ConvertToPolyline(curveObj));
                    origDBObjects.RemoveAt(i);
                }

                //iterate through each polyline within entities collection
                for (int i = 0; i < origDBObjects.Count; ++i)
                {
                    for (int j = i + 1; j < origDBObjects.Count; ++j)
                    {
                        Polyline pl1 = origDBObjects[i] as Polyline;
                        Polyline pl2 = origDBObjects[j] as Polyline;
                        Point3dCollection points = new Point3dCollection();

                        //test for intersection(s)
                        pl1.IntersectWith(pl2, Intersect.OnBothOperands, points, IntPtr.Zero, IntPtr.Zero);

                        //validation for intersections
                        foreach (Point3d point in points)
                        {
                            // Skip the start/end points since they are connected vertices
                            if (point == pl1.StartPoint ||
                                point == pl1.EndPoint)
                            {
                                if (point == pl2.StartPoint ||
                                    point == pl2.EndPoint)
                                {
                                    // If two consecutive segments, then skip
                                    if (j == i + 1)
                                    {
                                        continue;
                                    }
                                }
                            }

                            //if genuine intersection detected, create temporary circle of specified radius at intersection
                            foreach (Point3d pt3d in points)
                            {
                                Circle c = new Circle();
                                c.Center = pt3d;
                                c.Radius = 0.5;
                                circleDBObjects.Add(c);
                            }
                        }
                    }
                }

You could also combine the code like so:

Code - Auto/Visual Lisp: [Select]

1. (if (setq sel1 (ssget "_X" '((0 . "MULTILEADER"))))
2.   ;;multi-leader
3.   (repeat (setq int1 (sslength sel1))
4.     (setq obj1 (vlax-ename->vla-object (ssname sel1 (setq int1 (1- int1)))))
5.     (setq sn (strcase (vla-get-stylename obj1)))
6.     (cond ((= sn "LDR_L100_RED") (vla-put-stylename obj1 "LDR_L100"))
7.      ((= sn "LDR_LS100_RED") (vla-put-stylename obj1 "LDR_LS100"))
8.     )
9.   )
10. )

I figured there was a way shorter method. I did try (cond...but not like that.


Thanks for that, RonJonP.

And once again...never mind, I found the error of my ways.

I'm clearly missing something here.

When I use these two routines as separate lisp routines, they work fine.

But if I place them together in the same lisp, both "RED" LDR's get changed to LDR_LS100.

Code - Auto/Visual Lisp: [Select]

1.  (if (setq sel1 (ssget "_X" '((0 . "MULTILEADER"))));;multi-leader
2.    (repeat (setq int1 (sslength sel1))
3.     (setq obj1 (vlax-ename->vla-object (ssname sel1 (setq int1 (1- int1)))))
4.     (progn (eq (vla-get-stylename obj1) "LDR_L100_RED")
5.        (vla-put-stylename obj1 "LDR_L100")
6.        )
7.      )
8.    )
9.  
10.   (if (setq sel2 (ssget "_X" '((0 . "MULTILEADER"))));;multi-leader
11.    (repeat (setq int2 (sslength sel2))
12.     (setq obj2 (vlax-ename->vla-object (ssname sel2 (setq int2 (1- int2)))))
13.     (progn (eq (vla-get-stylename obj2) "LDR_LS100_RED")
14.        (vla-put-stylename obj2 "LDR_LS100")
15.        )
16.      )
17.    )

What am I missing?

Should be

Quote from: Peter2 on November 03, 2020, 04:53:00 AM

@lamarn

on your picture there is manually added "AutoCAD" to the list. I'm surprised that pure Autocad also supports Dynamo?

It doesn't. You can create or read from AutoCAD objects but only in the Civil 3D environment.

Autodesk marketing at work! boooo Autodesk

Thanks for sharing Jeff!