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Introduction to AutoCAD 2009 2D and 3D Design- P2

Introduction to AutoCAD 2009 2D and 3D Design- P2: The purpose of writing this book is to produce a text suitable for students in Further and/or Higher Education who are required to learn how to use the CAD software package AutoCAD 2009. Students taking examinations based on computer-aided design will fi nd the contents of the book of great assistance. | 38 Introduction to AutoCad 2009 CHAPTER 2 Fig. 2.20 The Undo tool in the Standard Annotation toolbar Everything done during a session in constructing a drawing can be undone by repeated clicking on the Undo tool icon or by entering u s at the command line. To bring back objects that have just been removed by the use of Undo s left-click the Redo tool icon in the Standard Annotation toolbar Fig. 2.21 or enter Redo at the command line. Drawing with the Polyline tool Fig. 2.21 The Redo tool icon in the Standard Annotation toolbar When drawing lines with the Line tool each line drawn is an object in its own right. A rectangle drawn with the Line tool is four objects. A rectangle drawn with the Polyline tool is a single object. Lines of different thickness arcs arrows and circles can all be drawn using this tool as will be shown in the examples describing constructions using the Polyline tool. Constructions resulting from using the tool are known as polylines or plines. The Polyline tool can be called from the Home Draw panel Fig. 2.22 or by entering pl at the command line. Fig. 2.22 The Polyline tool icon in the Home Draw panel Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. Introducing drawing 39 First example - Polyline tool Fig. 2.23 30 250 230 250 CHAPTER 2 30 120 230 120 Fig. 2.23 First example - Polyline tool Note In this example enter and right-click have not been included. Left-click the Polyline tool. The command line shows Command _pline Specify start point 30 250 Current line width is 0 Specify next point or Arc Halfwidth Length Undo Width 230 250 Specify next point or Arc Close Halfwidth Length Undo Width 230 120 Specify next point or Arc Close Halfwidth Length Undo Width 30 120 Specify next point or Arc Close Halfwidth Length Undo Width c Close Command Note 1. Note the prompts - Arc for constructing pline arcs Close to close an outline Halfwidth to halve the width of a wide pline Length to enter the required length of a pline .