### CAP 201a - Computer Animation I

#### Lesson 6 - Low-poly Modeling

##### Objectives:

This lesson discusses sub-objects and shows the user how to modify an object and its sub-objects. Objectives important to this lesson:

1. Types of surfaces
2. Sub-objects of meshes
3. Modeling sub-objects or modeling with modifiers
4. Selecting sub-objects
5. Smoothing
6. Subdivision surfaces
##### Concepts:

The lesson begins by stating that objects in 3DS Max are made of sub-objects. You can work with the sub-objects of an object, but you cannot modify the entire object while you are modifying one of its sub-objects. It is a matter of focus: you are either working at the object level or the sub-object level at any given time.

The lesson introduces the concept of box modeling, which can be applied to other primitive objects as well as boxes. The idea is to start with a general shape, then modify parts of it to match your needs. To do this, you must edit the details of an object, its sub-objects. You can add a modifier to allow this, or you can convert the object to an editable poly object. (Poly refers to polygon and polyhedron.) The book also says you can make the object an editable mesh, but that this is an older tool with fewer features.

##### Exercise Notes and Questions

Note: You get it by now, right? Do the exercises.

Work through the exercises and turn in your answers to all questions below as part of the homework for this assignment.

Exercise 1: This exercise starts with a scene that includes a sphere. You are instructed to add an Edit Poly modifier to the sphere. You are also told to use the Convert To command from the Quad menu for the sphere to change it to an Editable Poly object.
Question 1: What can you do after adding the Edit Poly modifier that you cannot do once you change the object to an Editable Poly?

The lesson continues with a summary of the kinds of sub-object editing you can do on an editable poly object:

• vertex - all the points you see in wireframe view (Selection icon is three dots)
• edge - any line connecting two vertices is an edge (Selection icon is a triangle)
• border - borders are sets of edges that surround open holes in an object, like the rim of an empty can (Selection icon is a kidney shape)
• polygon - a polygon is a surface bounded by edges; with this tool you can select multiple surfaces on the object (Selection icon is a square)
• element - an element is a series of connected polygons (Selection icon is a cube)

Exercise 2: Exercise 2 works with a model of an engine, showing you how to use the sub-object tools listed above. Note that you can select a tool from a list of sub-objects of the Editable Poly, (shown on the right, in the Modifier List ), or you can click the associated graphic on the Selection rollout (sub-panel).
Question 2: What effect does the Grow button on the Selection rollout have if you have selected a polygon?

Exercise 3: This exercise lets you add more features to the engine model.
Question 3: What does the Extrude command do in this exercise?
Question 4: What is the effect, in step 11, of dragging a selected polygon?

The second half of this exercise is needlessly complex. Try to follow the steps starting on page 200, but if it becomes too difficult to follow, proceed to exercise 4.

Exercise 4: Exercise 4 shows us the Bend tool. In step 23, you are directed to use the Chamfer button.
Question 5: The text does not explain a chamfer. What is a better description of the effect?
Question 6: The exercise also uses the Attach command. How do you attach one object to another?

Exercise 5: Exercise 5 shows us the Cap command.
Question 7: What does the Cap command do in this exercise?

Exercise 6: Exercise 6 uses an unfinished model to show that we can use Smoothing Groups to smooth the rough edges of a new element added to a model.

Exercise 7: Exercise 7 uses a modifier to smooth the unfinished model.
Question 8: What warning does the text give us about Iterations in the TurboSmooth modifier?