开发:修复错误

src/Add-on/DrawLine.ts

@@ -160,7 +160,7 @@ export class DrawLine implements Command
                 //第一个是切点 第二个也是选切点
                 if (ptRes.SnapMode === ObjectSnapMode.Tan && firstTangeCircle && pts.length === 1)
                 {
-                    let pick = new SelectPick(app.Viewer, app.Viewer.WorldToScreen(ptRes.Point), app.Editor.GetPointServices.snapServices.SnapSize);
+                    let pick = new SelectPick(app.Viewer, app.Viewer.WorldToScreen(ptRes.Point.clone()), app.Editor.GetPointServices.snapServices.SnapSize);
                     pick.Select(app.Viewer.VisibleObjects, { filterTypes: [Circle, Arc] });
                     let secondTangeCircle: Circle = (pick.SelectEntityList as Circle[]).find(c => c.PtInCurve(ptRes.Point));