Introduction to 3 D Drawing Ipek Gursel Office

Introduction to 3 D Drawing Ipek Gursel Office: A 301 igursel@yediyepe. edu. tr Dec 13, 2005

Outline o 3 D drawing: Perspective n n n o Types Examples Assignment A brief introduction to Auto. CAD

Perspective: a definition. . . o o the technique of representing threedimensional objects and depth relationships on a two-dimensional surface. may be used in paintings, architectural space representations, computer graphics, multimedia applications, computer games, etc.

types. . . 1. paraline (orthographic) n n isometric axonometric 2. conical

ISOMETRIC the angles between the projection of the x, y, and z axes are all the same; 120°.

An example Plan Front view Side view

An example Plan Side view Front view

Lets draw a simple rectangle… 10 3 5 1. Lets draw the x, y and z axis. 2. Measure off height, depth and length 3. Draw your solid lines 3 5 10

A hands on exercise… 8 8 8 2 4 2 2

A brief introduction to: AUTOCAD

What is Auto. CAD o o o Auto. CAD is a computer-aided drafting (CAD) software package for 2 D and 3 D design and drafting, developed and sold by Autodesk. It currently runs exclusively on Microsoft operating systems. Versions for Unix and Mac were released (until R 13), but these met with limited market acceptance and were later dropped. Architects and engineers (AEC), drafters, cartographers, and other professionals involved with design We have Auto. CAD 2006 installed in our machines

Some basics… o o 3 d space: all objects are three dimensional in real life. However, we cannot represent the third dimension on a 2 d surface, such as a piece of paper or your monitors. So we use the Cartesian coordinate system on the 3 d world of a CAD tool (remember your analytical geometry courses). All the points in your space is defined by its x, y and z coordinates. In other words, Auto. CAD uses points to determine where an object is located. y (6, 4, 0) z (0, 0, 5) (0, 0, 0) (3, 2, 5) y (3, 0, 5) (3, 0, 0) x (2, 1, 0) x

UCS and WCS o o The Auto. CAD world is 3 dimensional. However, if we want to draw a 2 d object, such as a plan or a section, we will use only 2 dimensions (x and y). WCS (world coordinate system) is the imaginary plane that is parallel to the ground. It is the default coordinate system. Modifications made to the World Coordinate System (WCS) result in a User Coordinate System (UCS). It is the plane that you work on. It enables the user to draw 3 dimensional objects. To create a new UCS, type ucs on the command window, then say New and specify 3 points on your new UCS plane.

How do we give a command? o o o Command line Toolbars Drop-down menus You can pick any one(s) that you are comfortable with.

Next week: o o o We will learcn to draw simple shapes, both 2 D and 3 D) with Auto. CAD. We will have hands-on exercises. This week’s assignment is due Thursday, March 9. You will hand in the completed assignment sheets.