Trying to mirror a drawing using the AutoCAD class on C#

Question

Currently I have an object drawn using the AutoCAD class but I the option to mirror it once drawn. I'm not sure how to go about this.

[CommandMethod("DrawTestDoor")]
        public void DrawTestDoor()
        {
            Document acDoc = Application.DocumentManager.MdiActiveDocument; 
            var ed = acDoc.Editor;
            XDDoor s1 = new XDDoor();
            PromptKeywordOptions pKeyOpts = new PromptKeywordOptions("");
            pKeyOpts.Message = "\nIt is Rated ";
            pKeyOpts.Keywords.Add("True");
            pKeyOpts.Keywords.Add("False");
            pKeyOpts.Keywords.Default = "True";
            pKeyOpts.AllowNone = true;
            PromptResult pKeyRes = acDoc.Editor.GetKeywords(pKeyOpts);
            bool fireRated = Convert.ToBoolean(pKeyRes.StringResult);

            var promptResultheight = ed.GetString("\nEnter the Frame height: ");
            double height = Convert.ToDouble(promptResultheight.StringResult);

            var promptResultwidth = ed.GetString("\nFrame Width: ");
            double width = Convert.ToDouble(promptResultwidth.StringResult);

            var promptResultFrameDepthChange = ed.GetString("\nEnter the frame depth change ");
            double frameDepthChange = Convert.ToDouble(promptResultFrameDepthChange.StringResult);

            PromptKeywordOptions pKeyOpts1 = new PromptKeywordOptions("");
            pKeyOpts1.Message = "\nDoor Handle Side";
            pKeyOpts1.Keywords.Add("Left");
            pKeyOpts1.Keywords.Add("Right");
            pKeyOpts1.Keywords.Default = "Left";
            pKeyOpts1.AllowNone = true;
            s1.DrawSingleXDDoor(height, width, fireRated, frameDepthChange);
            Matrix2d md = new Matrix2d();
            md.Translation.Mirror()
        }

This md.Translation.Mirror() is the line that I think needs changed. I have tried numerous ways to do the mirror but I keep coming back to the issue with I dont know what the s1 object is being saved as as such. Maybe thinking it needs converted to an entity?

public void DrawSingleXDDoor(double height, double width, bool fireRated, double frameDepthChange)
        {
            DrawLid("lid", leafHeight, lidWidth);
        }

public void DrawLid(string type, double height, double width)
        {
            DrawShapes d1 = new DrawShapes();
            DrawComponents xd = new DrawComponents();
            d1.DrawRectangle(0, 0, height, width);
        }
public void DrawRectangle(double startx, double starty, double recHeight, double recWidth)
        {
            double height = recHeight;
            double width = recWidth;
            //Get the drawing document and the dataabses object
            Document doc = Application.DocumentManager.MdiActiveDocument;
            Database db = doc.Database;
            using (Transaction trans = db.TransactionManager.StartTransaction())
            {
                try
                {
                    BlockTable bt;
                    bt = trans.GetObject(db.BlockTableId, OpenMode.ForRead) as BlockTable;

                    BlockTableRecord btr;
                    btr = trans.GetObject(bt[BlockTableRecord.ModelSpace], OpenMode.ForWrite) as BlockTableRecord; 
                    Polyline p1 = new Polyline();
                    p1.AddVertexAt(0, new Point2d(startx + 0, starty + 0), 0, 0, 0);
                    p1.AddVertexAt(0, new Point2d(startx + 0, starty + height), 0, 0, 0);
                    p1.AddVertexAt(0, new Point2d(startx + width, starty + height), 0, 0, 0);
                    p1.AddVertexAt(0, new Point2d(startx + width, starty + 0), 0, 0, 0);
                    p1.AddVertexAt(0, new Point2d(startx + 0, starty + 0), 0, 0, 0);
                    p1.SetDatabaseDefaults();
                    btr.AppendEntity(p1);
                    trans.AddNewlyCreatedDBObject(p1, true);
                    trans.Commit();
                }
                catch (System.Exception ex)
                {
                    doc.Editor.WriteMessage("Error encountered: " + ex.Message);
                    trans.Abort();
                }
            }

        }

Answer 1

This example was pulled from AutoCAD 2017 .Net SDK.

It looks like you missed setting the mirror point on the transform and insert the mirrored copy to the BlockTable . The code below should execute directly after adding your new p1 (polyline) . I got this code sample from here . Give it a shot and let me know. Cheers!

 // Define the mirror line
        Point3d acPtFrom = new Point3d(0, 4.25, 0);
        Point3d acPtTo = new Point3d(4, 4.25, 0);
        Line3d acLine3d = new Line3d(acPtFrom, acPtTo);

        // Mirror the polyline across the X axis
        acPolyMirCopy.TransformBy(Matrix3d.Mirroring(acLine3d));

        // Add the new object to the block table record and the transaction
        acBlkTblRec.AppendEntity(acPolyMirCopy);
        acTrans.AddNewlyCreatedDBObject(acPolyMirCopy, true);

Answer 2

It has taken me till now to figure this out. Many trials and errors. I will do my best to give as much code as possible with an example

arrays.cs

        public void PopulateWithOldArray(List<double> newArray, List<double> oldArray, bool negate)
        {
            //if there are any previous version of the new array we want them to be cleared so that the called old array will not be affected
            newArray.Clear();
            if (negate == true)
            {
                for (int i = 0; i < oldArray.Count; i++)
                {
                    newArray.Add(-oldArray[i]);
                }
            }
            else
            {
                for (int i = 0; i < oldArray.Count; i++)
                {
                    newArray.Add(oldArray[i]);
                }
            }
        }//end PopulateWithOldArray


        public void MirrorXaxis(double startx, double starty, List<double> x, List<double> y, List<double> angle)
        {
            List<double> changedx = new List<double> { };
            List<double> changedangle = new List<double> { };
            PopulateWithOldArray(changedx, x, true);
            PopulateWithOldArray(changedangle, angle, true);
            DrawShapes ds = new DrawShapes();
            for (int i = 0; i < angle.Count; i++)
            {
                ds.DrawPolyLine(changedx[i] + startx, y[i] + starty, changedx[i + 1] + startx, y[i + 1] + starty, changedangle[i]);
            }//end for
        }//end mirror

drawshapes.cs

using System;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.Geometry;
using Autodesk.AutoCAD.EditorInput;

namespace doorsetsDraw
{
class DrawShapes
    {
       public void DrawPolyLine(double startx, double starty, double endx, double endy, double endBulgeAngle)
        {
            //Get the drawing document and the dataabses object
            Document doc = Application.DocumentManager.MdiActiveDocument;
            Database db = doc.Database;

            //create the transaction object inside the using block
            using (Transaction trans = db.TransactionManager.StartTransaction())
            {
                try
                {
                    //get the blocktable object
                    //doc.Editor.WriteMessage("Drawing a 2d Polyline!"); //extra option to last editor
                    BlockTable bt;
                    bt = trans.GetObject(db.BlockTableId, OpenMode.ForRead) as BlockTable;

                    BlockTableRecord btr;
                    btr = trans.GetObject(bt[BlockTableRecord.ModelSpace], OpenMode.ForWrite) as BlockTableRecord; //draw into model space

                    //specify the polyline's coordinates
                    Polyline p1 = new Polyline();

                    p1.AddVertexAt(0, new Point2d(startx, starty), 0, 0, 0);

                    p1.AddVertexAt(0, new Point2d(endx, endy), BulgeEquationTan(endBulgeAngle), 0, 0);

                    p1.SetDatabaseDefaults();
                    btr.AppendEntity(p1);
                    trans.AddNewlyCreatedDBObject(p1, true);
                    trans.Commit();
                }
                catch (System.Exception ex)
                {
                    doc.Editor.WriteMessage("Error encountered: " + ex.Message);
                    trans.Abort();
                    //abort to roll out of excpetion for unreferenced object
                }//end catch
            }//end using
        }//end drawpolylineElip

        public double BulgeEquationTan(double angleD)
        {
            double tanV = ConvertToRadians(angleD) / 4;
            double tanA = Math.Tan(tanV);
            return tanA;
        }//end BulgeEquationTan

        public double ConvertToRadians(double angle)
        {
            return (Math.PI / 180) * angle;
        }//end ConvertToRadians
}
}