topic Re: Get text (MText) entity (inside) a polyline or block in .NET Forum

Get text (MText) entity (inside) a polyline or block

Anonymous — Wed, 26 Nov 2014 08:46:49 GMT

Hi All

I need to get (read) a text entity that resides (inside) a polyline or inside a block.

Thanks in advance for your help.

Re: Get text (MText) entity (inside) a polyline or block

SENL1362 — Wed, 26 Nov 2014 12:26:51 GMT

        //Note: both arguments may be virtual, i.e. not added to te database, therefore db as separate argument
        public static bool IsPartialInside(Database db, Polyline poly, ObjectId entId)
        {
            bool isPartialInside=false;
            using (Transaction tr = db.TransactionManager.StartTransaction())
            {
                Entity ent=(Entity)tr.GetObject(entId, OpenMode.ForRead);
                isPartialInside = IsPartialInside(poly, ent);

                tr.Commit();
            }

            return isPartialInside;
        }

        //Note: both arguments may be virtual, i.e. not added to te database
        public static bool IsPartialInside(Polyline poly, Entity ent)
        {
            try
            {
                //Quick scan based on Bounding Box
                if (ent.GeometricExtents.MinPoint.X > poly.GeometricExtents.MaxPoint.X)
                    return false;
                if (ent.GeometricExtents.MinPoint.Y > poly.GeometricExtents.MaxPoint.Y)
                    return false;
                if (ent.GeometricExtents.MinPoint.Z > poly.GeometricExtents.MaxPoint.Z)
                    return false;

                if (ent.GeometricExtents.MaxPoint.X < poly.GeometricExtents.MinPoint.X)
                    return false;
                if (ent.GeometricExtents.MaxPoint.Y < poly.GeometricExtents.MinPoint.Y)
                    return false;
                if (ent.GeometricExtents.MaxPoint.Z < poly.GeometricExtents.MinPoint.Z)
                    return false;

                Point3dCollection plPoints = AcadPolyTools.PolyToPoints(poly);
                Point3dCollection entPoints = GetBoundingPoints(ent);
                //add center of entity
                entPoints.Add(new Point3d(
                                            0.5 * (ent.GeometricExtents.MinPoint.X + ent.GeometricExtents.MaxPoint.X),
                                            0.5 * (ent.GeometricExtents.MinPoint.Y + ent.GeometricExtents.MaxPoint.Y),
                                            0.5 * (ent.GeometricExtents.MinPoint.Z + ent.GeometricExtents.MaxPoint.Z)));

                foreach (Point3d point in entPoints)
                    if (IsInside(plPoints, point))
                        return true;
            }
            catch
            {
                //if (ent is DBText)
                //{
                //    DBText tmpText = (DBText)ent;
                //    Document doc = Application.DocumentManager.MdiActiveDocument;
                //    Database db = doc.Database;
                //    Editor ed = doc.Editor;

                //    ed.WriteMessage("\n ***ToDo: SkipEmptyObjects: TextString='', Polyline.length=0, LineLength=0");
                //}
            }

            return false;
        }

        public static bool IsInside(Point3dCollection polyPoint, Point3d pnt)
        {
            int i, j = polyPoint.Count - 1;
            bool oddNodes = false;

            for (i = 0; i < polyPoint.Count; i++)
            {
                Point3d pi = polyPoint[i];
                Point3d pj = polyPoint[j];

                //quicker for large number of points to test, but need Init procedure for Multiple[] and Constant[]
                //if ((pi.Y < pnt.Y && pj.Y >= pnt.Y || pj.Y < pnt.Y && pi.Y >= pnt.Y))
                //    oddNodes ^= (pnt.Y * Multiple[i] + Constant[i] < pnt.X);


                if ((pi.Y < pnt.Y && pj.Y >= pnt.Y || pj.Y < pnt.Y && pi.Y >= pnt.Y) &&
                    (pi.X <= pnt.X || pj.X <= pnt.X))
                    oddNodes ^= (pi.X + (pnt.Y - pi.Y) / (pj.Y - pi.Y) * (pj.X - pi.X) < pnt.X);

                j = i;
            }
            return oddNodes;
        }

        public static Point3dCollection PolyToPoints(Polyline pl)
        {
            Point3dCollection plPoints = new Point3dCollection();

            for (int i = 0; i < pl.NumberOfVertices; i++)
                plPoints.Add(pl.GetPoint3dAt(i));
            return plPoints;
        }

Re: Get text (MText) entity (inside) a polyline or block

_gile — Thu, 27 Nov 2014 12:48:17 GMT

Hi,

To check if a point is inside a polyline, two ways are described here, one using a MPolygon, the other using the BoundaryRepresentation (Brep) API.

Re: Get text (MText) entity (inside) a polyline or block

SENL1362 — Thu, 27 Nov 2014 13:13:44 GMT

Hi Gile,
I'm normally a big fan of TT code but the BREP solution appeared to be too slow for my particular problem.
I wasn't aware of the MPolygon functionality and thus converted old C code into a C# solution.
I might have a look at the MPolygon object later on, the code seems to be short and easy which is always good.
Thanks to point me into that direction.

Re: Get text (MText) entity (inside) a polyline or block

Anonymous — Thu, 08 Jan 2015 06:16:16 GMT

Hi Giles

Thank you for your time.

i wrote polyline instead of polygon mistakenly in the title, sorry for that.
I tried the two ways, they work fine with normal polyline. i tried to use the code with polygone but it reads the polygon as a polyline>
Also tried to convert the polygon to a polyline but i failed.
My problem exactly that i need to search for BlockReferences or polygons on PS or MS, then find any Text (Inside) the block or (Inside) the polygon.
The BlockReferences option is my favourite, but it is not necessary.