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Brigham Young University Department of Civil & Environmental Engineering CEEn 112 – Engineering Drawing with CAD Application Harnessing AutoCAD 2006 Chapter Summaries

CHAPTER 15-C. AUTOCAD 3D (PP. 837-842) & RENDERING BASICS (Chapter 16) (pp. 887-894, 900-903) Objective:  In this lecture we will review some of the commands that we talked about last class to quickly construct surfaces. We will also learn how to edit 3D objects and will discuss briefly the basics of rendering from Chapter 16.

Topics Covered: A) Creating Meshes (review)

1. Mesh  3DMESH – Used to define a free-form 3D polygon mesh. commands  PFACE – Used to construct a mesh of any topology you desire.  RULESURF – Used to create a mesh between two objects.  TABSURF – Used to create a surface extrusion from an object with a length and direction determined by the direction vector.  REVSURF – Used to create a 3D mesh that follows the path defined by a path curve rotated around a centerline.  EDGESURF – Used to create a mesh with four adjoining sides defining its boundaries.  Note: All surface created objects can be exploded into individual 3D faces. Also, meshes created by these commands can be edited just like other objects by the PEDIT command.

B) Editing in 3D

1. Aligning  ALIGN – Allows the user to translate and rotate objects in 3D space objects regardless of the position of the current UCS. Three source points and three destination points define the move (pp. 837-838).

2. Rotating  ROTATE3D – Used to rotate an object about an arbitrary 3D axis objects about a 3D (pp. 838-839). object  Several options are available for selecting the axis of rotation including: 2points, Object, Last, View, and X/Y/Zaxis.

3. Mirroring  MIRROR3D – Allows the user to mirror a selected object about a about a plane plane (pp. 839-840).  Several options are available for the mirroring plane including: Page 2

3points, Object, Last, Zaxis, View, XY/YZ/XZ.

4. Creating a 3D  3DARRAY – Used to make multiple copies of selected objects in array either rectangular or polar array in 3D (pp. 840-841).  In the rectangular array, specify the number of columns (X direction), the number of rows (Y direction), the number of levels (Z direction), and the spacing between columns, rows, and levels.  In the polar array, specify the number of items to array, the angle that the arrayed objects are to fill, the start point and endpoint of the axis about which the objects are to be rotated, and whether or not the objects are rotated about the center of the group.

5. Extending and  EXTEND and TRIM can also be used on 3D objects. This trimming in 3D command can be used to extend or trim objects regardless of whether the objects are on the same plane or parallel to the cutting or boundary edges (pp. 841-842).

C) Rendering Basics (Chapter 16) (pp. 887-894, 900-903)

1. Shading a model  SHADEMODE – Lets you produce a shaded picture of the 3D model in the current viewport (pp. 887-888).  We will discuss more detail later, but play around with it now.

2. Rendering a model  RENDER – Allows you to create realistic models from your drawing (pp. 889-894).  For now, check the following three options: o Set the rendering type to “Photo Real,” o Set the destination to “Viewport,” and o Click the Render Scene button.  We will discuss this in more detail with Chapter 16.

3. Materials  RMAT – Gives you the power to modify the light reflection characteristics of the objects that you will render. There are several simple steps, but you will need to read these pages to understand them (pp. 900-903).  The primary steps involve calling up a material library, selecting a material (texture), importing it to your file, and then attaching it to the surfaces of your 3D modes. Then go back to the Render command.  To use special texture available in AutoCAD, you must render with other than the “AutoCAD Render” option, like “Photo Real,” so stick with the “Photo Real” render type.

CEEn 112 – Engineering Drawing with CAD Application Harnessing AutoCAD 2006 – Chapter 15C Summary