topic Re: get connected lines in .NET Forum

get connected lines

Anonymous — Mon, 31 Mar 2014 11:42:19 GMT

Hi,

How do I get all lines connected to a selected line. The lines can cross other lines ,they can share same start or end point or they can share common vertices. In all I mean to say that I want all lines connected/touching/intersecting lines to the selected line.

Thanks & Regards

Sanjay Pandey

Re: get connected lines

Anonymous — Mon, 31 Mar 2014 12:04:37 GMT

Entity.IntersectWith Method, Line is also a class derives from this abstract class

Re: get connected lines

Hallex — Mon, 31 Mar 2014 15:56:31 GMT

Change this code to your needs:

      //_____________________________________________________________________//
        //ads_queueexpr
        [DllImport("accore.dll", CharSet = CharSet.Unicode,
CallingConvention = CallingConvention.Cdecl,
EntryPoint = "ads_queueexpr")]
        extern static private int ads_queueexpr(byte[] command);


        [CommandMethod("tJL", CommandFlags.Modal | CommandFlags.UsePickSet)]
        public void TestConnectedLines()
        {
            Document doc = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument;

            Editor ed = doc.Editor;

            Database db = doc.Database;

            PromptEntityOptions pso = new PromptEntityOptions("\nPick a single line to join: ");

            pso.SetRejectMessage("\nObject must be of type Line!");

            pso.AddAllowedClass(typeof(Line), false);

            PromptEntityResult res = ed.GetEntity(pso);

            if (res.Status != PromptStatus.OK) return;
            using (DocumentLock doclock = doc.LockDocument())
            {
                using (Transaction tr = db.TransactionManager.StartTransaction())
                {

                   Autodesk.AutoCAD.ApplicationServices.Application.SetSystemVariable( "PICKFIRST",1); 
               Autodesk.AutoCAD.ApplicationServices.Application.SetSystemVariable( "PEDITACCEPT",0); 
                    BlockTableRecord btr = (BlockTableRecord)tr.GetObject(db.CurrentSpaceId, OpenMode.ForRead) as BlockTableRecord;

                    List<ObjectId> ids = JoinLines(btr, res.ObjectId);

                    ObjectId[] lines = ids.ToArray();
                    
                    ed.SetImpliedSelection(lines);
                 
                    PromptSelectionResult chres = ed.SelectImplied();
              
                    if (chres.Status != PromptStatus.OK)
                    {
                        ed.WriteMessage("\nNothing added in the chain!");

                        return;
                    }
                        else
                        {
                        ed.WriteMessage(chres.Value.Count.ToString());
                        }
                    SelectionSet newset = SelectionSet.FromObjectIds(lines);

                    ed.SetImpliedSelection(newset);
           
                    string handles = "";
                    foreach (SelectedObject selobj in newset)
                    {
                        
                        Entity subent = tr.GetObject(selobj.ObjectId, OpenMode.ForWrite) as Entity;
                        string hdl=string.Format("(handent \"{0}\")",subent.Handle.ToString());
                        handles= handles + hdl + " ";
                  
                    }
                    System.Text.UnicodeEncoding uEncode = new System.Text.UnicodeEncoding();
                 // if PEDITACCEPT is set to 1 enshort the command avoiding "_Y" argument:
                    ads_queueexpr(uEncode.GetBytes("(COMMAND \"_.PEDIT\" \"_M\"" + handles  +  "\"\"" +  "\"_Y\" \"_J\" \"\" \"\")"));

                    tr.Commit();
                }
            }
        }

        private void SelectConnectedLines(BlockTableRecord btr, List<ObjectId> ids, ObjectId id)
        {
            Entity en = id.GetObject(OpenMode.ForRead, false) as Entity;

            Line ln = en as Line;

            if (ln != null)

                foreach (ObjectId idx in btr)
                {
                    Entity ex = idx.GetObject(OpenMode.ForRead, false) as Entity;

                    Line lx = ex as Line;

                    if (((ln.StartPoint == lx.StartPoint) || (ln.StartPoint == lx.EndPoint)) ||

                        ((ln.EndPoint == lx.StartPoint) || (ln.EndPoint == lx.EndPoint)))

                        if (!ids.Contains(idx))
                        {
                            ids.Add(idx);

                            SelectConnectedLines(btr, ids, idx);
                        }
                }
        }

        public List<ObjectId> JoinLines(BlockTableRecord btr, ObjectId id)
        {
            List<ObjectId> ids = new List<ObjectId>();

            SelectConnectedLines(btr, ids, id);

            return ids;
        }

        //_____________________________________________________________________//

Re: get connected lines

BKSpurgeon — Fri, 17 Apr 2015 05:45:55 GMT

There is a built in autcad command called "FS" - fast selection or fast selection (can't remember which).

it selects lines which are connected to your main line.

If you switch FSMODE to "ON" you can also have all subsidiary lines selected if they are in any way connected to your main base line.

it's in the autocad 2015 version.

Re: get connected lines

BKSpurgeon — Mon, 20 Apr 2015 12:12:46 GMT

List<ObjectId> ids = JoinLines(btr, res.ObjectId);

for some reason, I cannot declare the List collection (see above) in Visual studio - intellisense is not coming up with that option.

any ideas?

Re: get connected lines

hgasty1001 — Mon, 20 Apr 2015 13:02:12 GMT

Hi,

Try importing: System.Collections.Generic Namespace into the class you are coding.

Gaston Nunez

Re: get connected lines

BKSpurgeon — Mon, 20 Apr 2015 22:01:02 GMT

excellent thank you!

for everyone's reference, also found that in addition to that, these two need to be added too:

using System.Collections.Generic;
using System.Runtime.InteropServices;

rgds

BK

Re: get connected lines

BKSpurgeon — Tue, 21 Apr 2015 00:37:07 GMT

// if PEDITACCEPT is set to 1 enshort the command avoiding "_Y" argument:
                    ads_queueexpr(uEncode.GetBytes("(COMMAND \"_.PEDIT\" \"_M\"" + handles  +  "\"\"" +  "\"_Y\" \"_J\" \"\" \"\")"));

what is the purpose of the above here?

When I sent to the ojbectarx reference guide to see what ads_queueexpr means i was meant with confusion:

ads_queueexpr Function
This function queues up the LISP expression expr to be executed the next time AutoCAD is quiescent and able to evaluate LISP expressions. This function should only be called from within the kLoadDwgMsg case in your acrxEntryPoint() function. Queued LISP expressions will be executed after the (s::startup) has been executed. Multiple calls to ads_queueexpr() from the kLoadDwgMsg callback are perfectly acceptable. They get queued up in the order of the calls. ads_queueexpr Function
Do not use ads_queueexpr() in any context other then the kLoadDwgMsg case of acrxEntryPoint(). To do so will have unpredictable results, and may even be damaging, because the queue may not be looked at until active AutoLISP evaluations, MENU items, and/or SCRIPT executions are all finished.

I do not understand much of the above.

any explanation was to what ads_queueexpr(uEncode.GetBytes("(COMMAND \"_.PEDIT\" \"_M\"" + handles + "\"\"" + "\"_Y\" \"_J\" \"\" \"\")")); does would be helpful.
since pedit is set to 0 the "\"_Y\" is omitted in my code leaving behind this: ads_queueexpr(uEncode.GetBytes("(COMMAND \"_.PEDIT\" \"_M\"" + handles + "\"\"" + " \"_J\" \"\" \"\")"));

Am i doing this right? Any assistance much appreciated.

Re: get connected lines

BKSpurgeon — Mon, 31 Jul 2017 00:59:53 GMT

For anyone reading this perhaps you can make use of the following routine Mr Gilles has kindly provided:

https://www.theswamp.org/index.php?action=post;quote=446965;topic=31865.15;last_msg=565479

it seems to work very quickly - incredibly quickly compared to the algorithm posted above. You will also need the GeometryExtensions Library also kindly provided by Mr Gilles.

good luck.

Re: get connected lines

kerry_w_brown — Mon, 31 Jul 2017 01:34:26 GMT

Here is a direct link to that post :

https://www.theswamp.org/index.php?topic=31865.msg446965#msg446965