Introduction to 3D Modeling - Digital River

1 Chapter Overview n 3 Chapter1 Introduction to 3D Modeling The lessons covered in this chapter familiarize you with 3D Modeling and how you view your designsas you create them. You also learn the coordinate system and how you can use it to help you create 3 Ddesigns. Creating 3D models of your designs helps you to refine your ideas because you can visualize therelationship of design components. This same visualization of 3D models also helps you communicatethe design idea to others. Because of the need to communicate ideas to others, every design disciplinecan use 3D Modeling at some point in the design process. The lessons in this chapter teach you the methods, commands, and options for creating 3D covered include creating your designs with predefined shapes of different types, both solidand mesh.

2 Objectives After completing this chapter, you will be able to:nExplain the differences in 3D model types and how you view and display the solid models from primitive mesh models from primitive the 3D coordinate system, and how to define a custom coordinate system, control thedisplay of the coordinate system icon, and how to acquire a point in 3D and describe the design n Chapter 1: Introduction to 3D ModelingLesson: Introduction to 3D This lesson introduces you to 3D Modeling . It starts with an explanation of the types of 3D models youcan create and how you can change your viewing direction in 3D space to look at your designs fromdifferent directions. It then explains a few of the commands that you can use to change your viewingdirection, change the representation display of your models, and change the number of viewports andassociated displays within the drawing area.

3 The reason you create a design is to validate a concept and to communicate it to others. By creatingyour design as a 3D model, you are able to do both of these with a lot more clarity. In the following illustration, the drawing window is split into four equal viewports so the building andsite can be viewed in different directions. Each of the views is also set up to display the geometryslightly differently based on the designer's needs. Objectives After completing this lesson, you will be able to:nDescribe the types of 3D models and their the different ways you can view 3D the display of the models by changing the active visual the ViewCube and its and use the ViewCube to navigate in a 3D your model using Constrained and adjust model space : Introduction to 3D n 5 Types of 3D Models In this section of the lesson, you learn about the different types of 3D models you can create torepresent your designs.

4 While learning the differences between the types of models you can create,you will also learn the benefits of 3D Modeling . With the ability to identify the types of models andtheir benefits, you will be able to select the proper model type to create based on your criteria anddesign requirements. In the following illustration, the same floor plan is shown as a wireframe, a surface, and a solid model. Definition of 3D Model Types A primary benefit of 3D is the ability to visualize the design. By creating a 3D model, you can actuallysee how the different aspects come together. You can then use the 3D model to do a more effectivejob of communicating your design to others, not just those with the ability to read 2D blueprints. Aswell as seeing the design better, you can extract measurements from your design.

5 Depending on themodel type, those measurements can include distance, area, volume, and other mass solid models you can also check to see if other solid models, or components, interfere with eachother. Once you have the model created, you can also generate 2d drawing views for documentationpurposes. The extent of the benefits of a 3D model depends on which of the four model types you four Modeling types are as follows: nWireframe Model - The most basic form for 3D model representation. You draw lines, arcs, andcircles in 3D space to represent the edges of your design. Though this model type can be useful, itis often difficult to work with when creating a complex model with numerous edges. When viewinga wireframe model, you see all of the edges of the model regardless of which side of the modelyou are viewing Model - Mesh models approximate a smooth surface using a mesh of faces calledsubdivisions.

6 The more subdivisions there are, the smoother the surface appears. Tessellation linesrepresent the visual boundaries of each subdivision. Each subdivision has one face, no less thanthree and no more than four edges, and a corresponding number of vertices. Each subdivisionface, edge, or vertex can be edited independently by moving, rotating, or scaling it with the3D-Gizmo. The black lines on the model are called tessellation lines and visually represent theboundaries of each Model - A higher level of model representation, because it not only defines the edges ofthe design as in a wireframe model, but it also defines the outer skin or surface for the models can add clarity to the display of a design by hiding all geometry that resides behinda surface. While a surface model can return values for its surface area, it cannot return massproperty information because a surface has no true thickness, just a length and a Model - This model type defines the inner volume, outer surface, and edges of your designall within a single object.

7 Solid models represent all aspects of a design, and thus are the mostcomplete representational type of 3D model. You can create solid models from predefined shapesor from complex outlines. You can combine solid models together to create even more n Chapter 1: Introduction to 3D Modeling Example of 3D Model Types While you can create your designs as wireframe models, you will find solids, and sometimes surfacemodels, more useful to design with. If you need to model how the contour of land changes in an area,creating a surface model from contour lines at the various elevations is the most productive modelcreation method. You may also find creating surface models more practical if you are creating verythin-walled products like plastic bottles or the clear plastic packaging formed to hold merchandise.

8 Forall other designs such as buildings, bridges, desks, and mechanical parts, solid models offer you themost versatility in creating, editing, and displaying your design. In the following image, a 3D model of a new idea for material handling equipment was created tobetter discuss the design's merits and issues. Navigating and Displaying 3D Models As you create 3D models, it is important to view the model from different directions. Your ability toeffectively change the display of your model and the direction from which you view it has a directimpact on your ability to efficiently create and complete your design. In this next section, you learnabout the different ways you can change the direction from which you view your model, and otherways you can have it displayed.

9 In the following illustration, the same design is being viewed from three different directions. Witheach view, you are able to get a better understanding of the design. Lesson: Introduction to 3D n 7 Navigation and Display Defined When working in 3D, you typically need to look at different sides of your design. To view the differentsides, you do not reorient the model in 3D space. Instead, you change your viewing position in 3 Dspace by selecting one of the predefined viewing directions on the ViewCube or by orbiting the modelusing other navigation tools, such as Constrained Orbit, Free Orbit, or the Steering Wheel. Preset Viewing Directions The preset viewing directions include top, bottom, front, back, left, right, and four additional isometricviews.

10 These preset viewing directions are based on the default alignment of the X, Y, and Z coordinatesystem. For example, the top view looks straight down the Z axis at the X, Y plane, while the frontview looks in the direction of the Y axis at the X, Z plane. Use the ViewCube to quickly change fromone viewing direction to another or to establish a start point from which you can orbit to the exactrequired viewing direction. Orbiting Your View When orbiting your view, the pivot point is the center of a bounding box around the geometry. Thisbounding box is a mathematical box that is just large enough to encompass either all of the geometryin your drawing or just the geometry you select. You can use the ViewCube or Orbit command toreorient your display by orbiting around the 3D model.