CAD二次开发之 会旋转的彩色风车

/// <summary>
        /// 会旋转的风车
        /// </summary>
        [CommandMethod("RotatingFan")]
        public void RotatingFan()
        {
            var doc = Application.DocumentManager.MdiActiveDocument;
            var db = doc.Database;
            ObjectId id;
            BlockTableRecord btr = new BlockTableRecord();
            double radius = 500;
            double rad2deg = Math.PI / 180;
            Point3d center = Point3d.Origin;
            using (var lockDoc = doc.LockDocument())
            {


                using (var tr = db.TransactionManager.StartTransaction())
                {

                    Circle circle = new Circle(center, Vector3d.ZAxis, radius);
                    Line line1 = new Line(new Point3d(center.X - radius, center.Y, 0), new Point3d(center.X + radius, center.Y, 0));
                    Line line2 = new Line(new Point3d(center.X, center.Y - radius, 0), new Point3d(center.X, center.Y + radius, 0));
                    Arc arc1 = new Arc(new Point3d(center.X + radius / 2, center.Y, 0), Vector3d.ZAxis, radius / 2, 0 * rad2deg, 180 * rad2deg);
                    Arc arc2 = new Arc(new Point3d(center.X - radius / 2, center.Y, 0), Vector3d.ZAxis, radius / 2, 180 * rad2deg, 360 * rad2deg);
                    Arc arc3 = new Arc(new Point3d(center.X, center.Y + radius / 2, 0), Vector3d.ZAxis, radius / 2, 90 * rad2deg, 270 * rad2deg);
                    Arc arc4 = new Arc(new Point3d(center.X, center.Y - radius / 2, 0), Vector3d.ZAxis, radius / 2, 270 * rad2deg, 450 * rad2deg);
                    arc1.ColorIndex = 1;
                    arc2.ColorIndex = 2;
                    arc3.ColorIndex = 3;
                    arc4.ColorIndex = 4;
                    btr.AppendEntity(circle);
                    btr.AppendEntity(line1);
                    btr.AppendEntity(line2);
                    btr.AppendEntity(arc1);
                    btr.AppendEntity(arc2);
                    btr.AppendEntity(arc3);
                    btr.AppendEntity(arc4);


                    var bt = tr.GetObject(db.BlockTableId, OpenMode.ForWrite) as BlockTable;
                    id = bt.Add(btr);
                    tr.AddNewlyCreatedDBObject(btr, true);


                    var ms = tr.GetObject(bt[BlockTableRecord.ModelSpace], OpenMode.ForWrite) as BlockTableRecord;
                    var br = new BlockReference(new Point3d(100, 100, 0), id);
                    id = ms.AppendEntity(br);
                    tr.AddNewlyCreatedDBObject(br, true);


                    tr.Commit();


                    using (ViewTableRecord view = new ViewTableRecord())
                    {
                        db.UpdateExt(true);
                        Point3d max = db.Extmax;
                        Point3d min = db.Extmin;
                        Point2d max_2d = new Point2d(max.X, max.Y);
                        Point2d min_2d = new Point2d(min.X, min.Y);
                        view.CenterPoint = new Point2d(min_2d.X + (max_2d.X - min_2d.X) / 2, min_2d.Y + (max_2d.Y - min_2d.Y) / 2);
                        view.Height = (max_2d.Y - min_2d.Y);
                        view.Width = (max_2d.X - min_2d.X);
                        doc.Editor.SetCurrentView(view);
                        db.UpdateExt(true);
                    }
                }

            }
            //采用50Hz更新速率，每帧20ms
            int fps = 50;
            int frame = 1000 / fps;
            //基准速度0.01度每帧，也就是5度每秒
            double baseSpeed = 0.01;
            //可以通过调整速度系数，来调整旋转速率
            double speedFactor = 1;
            bool rotated = false;

            while (true)
            {
                var seconds = DateTime.Now.Millisecond;
                if (seconds % 20 == 0 && rotated == false)
                {
                    using (var lockDoc = doc.LockDocument())
                    {

                        using (var tr = db.TransactionManager.StartTransaction())
                        {
                            var br = tr.GetObject(id, OpenMode.ForWrite) as BlockReference;
                            br.Rotation += baseSpeed* speedFactor;
                            br.Rotation %= 360;
                            tr.Commit();
                        }

                    }

                    doc.Editor.UpdateScreen();
                    rotated = true;
                }
                if (seconds % 20 != 0 && rotated == true)
                {
                    rotated = false;
                }

            }
        }