CAP 201a - Computer Animation I

Lesson 2 - Chapter 4, Modeling (Part I)

Objectives:

This lesson continues the introduction to the software used for the course. Objectives important to this lesson:

1. Planning models
2. Modeling
3. Using modifiers
4. Mesh modifier or convert to mesh
5. Poly modifier or convert to poly
6. Modeling tools
7. Modeling project: chest of drawers/dresser
Concepts:

The chapter begins with a discussion about planning before creating a model. The authors makes a good point, that some objects that are included in a scene are not prominently featured in it. They appear only in the distance, or they are never manipulated in the scene, which makes it a waste of time to include a lot of detail or moving parts. Objects that are seen close up do need more detail to be convincing to a viewer. Objects that are manipulated in a scene do need moving parts, more flexibility, or other details that support their use.

Why not go for total quality (more detail) in every object in the scene? In a perfect world, you would. In the real world, you eliminate as many polygons (parts of objects) from a scene as you can to make the scene render and display faster, and to make the eventual movie created from the scene a smaller file.

There is another reason, discussed very well in an article on thinking like an artist by Stephen Worth, director of the ASIFA-Hollywood Animation Archive. You should read that article, and many others on that web site. For now, the point is that an artist need not include every possible detail in a scene to give the viewer the desired experience of that scene. Learn to use sufficient detail for your purpose.

The illustration on page 109 shows that the sphere the authors have made has several component parts. The sphere is constructed of lots of polygons (flat, closed shapes with a fixed number of sides). Since these are four-sided polygons, they each have four vertices (points that define the shape of the object). (Vertex is singular, vertices is plural.) A vertex may or may not seem to be a corner. A curved line has vertices, but it doesn't seem to have corners. This is an illusion. The reality is that it actually has corners. Let's define a corner as a point where the line segments change direction.

Vertices are connected by line segments, which are just called segments in 3DS Max. The segments are the edges of the object. It will be apparent from the illustration that adjacent objects share edges and vertices.

An area enclosed by the edges of one of the four-sided objects in our example is called a surface. In the case of these four-sided objects, each of the surfaces can also be broken down into two faces. A face is a triangular surface defined by three vertices. The illustration on page 109 shows one face of one polygon shaded darker than the rest of the figure. Polygons with more than four vertices will have more than two faces. (Number of faces = number of vertices - 2.) More on faces below.

The text explains that models are constructed from basic shapes that are combined and modified. Page 111 shows two sets of shapes that the text calls primitives and extended primitives. (Personally, I do not think that a teapot belongs in the primitive group, being much more complex than a box, a sphere, or any of the other shapes on that side of the page.)

To discuss modifying a shape, the text introduces the idea of turning a shape into a mesh. Mesh objects have sub-objects (e.g. vertices, edges, polygons) that you can modify. If this were network administration, I would tell you that a mesh is a network of redundantly connected points. This is similar to the spirit of what the text means, in that a mesh object allows us to modify its vertices, edges, polygons, etc. in a way that dynamically adds new connections where they are logically needed, as though those connections had always been there. If you move a segment, new connecting segments and vertices will appear if they are needed to avoid a break in the object's surface. (Unless you want a break. More on that later.)

To turn an object into a mesh, you have two options:

• add an Edit Mesh modifier to the object
• convert the object to an Editable Mesh (with its quad menu)

If you add a modifier to an object, you can still change the properties of the original object. If you convert an object to a mesh, you no longer have access to the original object's properties. If you add a modifier to an object, the file for the scene gets bigger and takes more memory to render than if you convert to a mesh (or a poly).

Exercise 1: Sphere with mesh modifier
This exercise starts on page 112. Create the sphere in a new scene and add the mesh modifier as indicated. Note: you can add the Edit Mesh modifier through the Modifier list on the Modify panel instead of using the menu option given in the text.
Question 1: Step 5 of the exercise tells you to select the icon to edit vertex sub-objects of the selected object. What is the selected object? (Note: you could have selected the named sub-object type from the list of sub-objects in the Modifier list instead of clicking the icon indicated.)
Question 2: What tool does step 6 tell you to use to modify vertices?

Exercise 2: Applying modifiers to a box
On page 115, you start an exercise that demonstrates the importance of the order in which modifiers are added to a stack. Note that the authors continue to add modifiers through the menu system. You may find that it easier to use the modifier list than to recall the menu commands. (I think it's easier to find it in an alphabetical list, rather than try to remember what category the Autodesk people think it belongs in.)
Question 3: What is the effect in step 6 of adding more height segments to the box?
Information about the stack continues through page 120.
Question 4: In what order does 3DS Max evaluate a modifier stack?

The text goes on to explain that you can choose between the Edit Mesh modifier and the Editable Mesh conversion, but you can also choose between the Edit Poly modifier and the Editable Poly conversion. The authors' preference is to use the Poly choices, because they are the more recently developed pair, and they offer manipulation tools that the authors prefer. Another difference is listed on page 124: meshes have faces as described above, but polys are composed of multi-sided polygons instead of faces. The authors like the fact that without faces, there isn't an unintended hinge in the middle of the polygons that form many objects.

The text introduces you to sub-objects that are commonly available in a mesh or a poly (converted or not). Note the three illustrations on page 123 showing tools for a sphere with an Edit Mesh modifier, Editable Mesh conversion, and Edit Poly modifier, respectively. The all show common sub-object icons that also appear in the image on the right, taken from a box converted to an Editable Poly (its nature changed when it was converted, but its name did not) :

• 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)

Once you make a selection of one of these types, you can modify the selection with the options described on page 126:

• Ignore backfacing - when this is turned off (default setting), you can select a sub-object that is not facing toward you; when it is turned on, you can only select sub-objects that are facing you. That is the theory. In the project that ends this section of the chapter, you may find that this setting does not really matter.
• Shrink - once you have made a selection that includes several sub-objects, the shrink command will systematically eliminate sub-objects from the selection set (the set of all sub-objects currently selected) to make the selected set smaller. Selected sub-objects farthest from the center of the selection set are removed from the selection set each time shrink is clicked.
• Grow - this is the opposite of shrink: the grow command adds the next nearest sub-objects to your selection set
• Loop - this is like grow, but more specific: the loop command will expand a selection set of edges to include all the contiguous edges that loop around the object in the same direction, forming a single continuous line

In the image above, I have created a box like the one in the illustrations in this part of the text. I gave it a number of sections to correspond to the image in the text, then converted it to an Editable Poly. I set the Perspective viewport to show Edged Faces. I have clicked on the Edge sub-object type, and selected one edge with the Select and Move tool. Note that the selected edge is shown in red, and the Move gizmo is shown with the proper colors for its three handles: RGB = XYZ.

In the image above, I have clicked the Loop button. Note that the selection set, shown as red edges, has been extended to include the edges that form a single line running around the circumference of the Editable Poly.

• Ring - this is like loop, but at 90 degrees: the ring command extends a set of selected edges to include all parallel edges that make a ring that runs at 90 degrees to the set that a loop would form. A loop forms a continuous line, but a ring does not.
In the image on the right, I clicked Undo (to undo the Loop command), then clicked the Ring button. Note that the only edge the two selection sets in these images have in common is the original selected edge. Although it looks like polygons are selected, they are not. Only a set of edges are selected.

Page 128 illustrates the difference between a soft selection and a hard selection. The authors created two spheres. They selected one vertex on the first sphere and extended it with a hard selection. This resulted in one point being moved away from the curve of the sphere, with polygons forming a steep slope back to the sphere. They selected a singe vertex on the second sphere, and extended it away from the sphere using settings on the Soft Selection rollout. This resulted in the point again being moved away from the body of the sphere, but this time the polygons leading back to the sphere formed a gentle, smooth slope. Note the use of the word falloff in this discussion. In general, this term means the area surrounding an effect that is partially changed by the effect. In this case, it means the extent of the effect over such a surrounding area.

The text continues, describing selection buttons that will extend your sub-object selection in useful ways. An exercise begins on page 128 that demonstrates several of them.

Exercise: Edit (Sub-object) Rollout
This exercise begins with a new sphere, as most of them do in this chapter, this time converted to an Editable Poly. In step 2, the authors tell you to select a poly. It will not matter much which one you choose.
Question 5: Steps 4 and 5 tell you how to use the Extrude tool with a selected polygon.
a. What is the difference in the result if you drag your mouse up the screen?
b. What about if you drag it down the screen?

On page 131, the text illustrates the use of some tools with a series of short exercises:

• Extrude - The text asks you to make a new sphere and to convert it to an Editable Poly. This time, choose the vertex sub-object, then choose the Edit Vertices rollout, and find the Settings button next to the Extrude button. That's the trick: there are separate Settings buttons for Extrude, Weld, and Chamfer on that rollout, and NONE of them are labeled. Each of those buttons looks like a decoration to the right of the button it provides settings for. Unless you know to look for them, those buttons may avoid your attention. Now you know. Try it out to practice finer control over an extrude operation.
• Chamfer - For this exercise, you choose three vertices in a line, then apply a Chamfer effect to them. The text explains that the Chamfer command adds new faces around selected sub-objects. In this case, each of the selected points becomes four points arranged around the location where each original point was.The general effect to is to smooth sharp edges.
• Weld - This tool fuses the chosen vertices at a point between them. The text asks you to weld two vertices on a sphere into one. The edges that led to the original vertices all change to connect to the new vertex. A more useful example will be seen later.
• Bevel - This tool can work like the extrude tool, but it can also modify the edges of shapes that connect to whatever you extrude.
• Outline - This tool lets you resize a polygon without changing its relative shape. It can also be used to add thickness to a spline.
• Inset - The text explains that this tool lets you shrink a polygon, while maintaining its shape and position.
• Hinge from Edge - This exercise will show you how to do part of an extrusion: you pick one edge of a polygon that will stay stationary, acting like a hinge, while the rest move.
• Cap - The Cap tool covers an indicated hole or gap in a model. Be aware that the cap the is formed will be flat, regardless of the curvature of the surrounding material.
• Extrude Along Spline - This is the last exercise before the first project for this chapter. The concept is fairly simple. First there must be an object in your scene that you will extrude a surface from. Second, there must be a spline, a line that may or may not be curved, that will act as a pattern for the extrusion. The command lets you create an extrusion that copies the shape of the spline. It does not necessarily flow along the spline. Note the example illustration on page 139 which shows the extrusion flowing beside the indicated spline. I suppose Extrusion That Mimics the Path of a Reference Spline would have been more accurate, but would also have been too long to use as a name.

The chapter turns to a modeling project: construction of a model chest of drawers. The text also calls the chest of drawers a dresser. Call it whichever you like. I will warn you that there are some errors in the instructions for this project. Most textbooks suffer from this problem, perhaps because proofreaders do not actually use the programs that authors describe.

The project begins with an echo about planning your model. Before you begin work in 3DS Max, you should know as much about the object you will be modeling as you can know. Reference photos, sketches, physical models, and measurements would all be sensible things to accumulate before modeling.

Quick test: study the reference picture of a chest of drawers on page 140 for 30 seconds. I will wait here.

Back already?
Question 6:
a. How many drawer rows are in the chest?
b. How many drawers are in the chest?
c. How many knobs are on the chest and what do they look like?
d. What does the top of of the chest look like?

This is to show you that one look may not be enough, and one reference photo is unlikely to be enough. You will do better modeling if you have multiple references to work from, and if you continue to use your references while you are modeling. For this project, I will expect some approximation, but this is a good time to become more precise.

In all of the exercises that follow (for the rest of your life), watch for decimal points, and for negative signs. Missing either of those things when setting a value will create a huge difference in your results.

Project Exercise 1: Top of the dresser

1. In step 1, the text says to begin a new scene with File, New, New All. Be aware that you can also start a new scene with File, Reset. This may not seem like a sensible command to start your scene over, but that's what it does.
Toggle the Edged Faces view for the Perspective Viewport as instructed. This will give you a better view of the object and sub-objects in this project. Open the Create panel, Geometry heading, and select Box.
2. In step 2, make sure you use the Keyboard Entry rollout, not the Parameters rollout. They are similar, but there is no Create button on the Parameters rollout, which is used in this step to create your preconfigured box at the default location in the scene.
Question 7: Where is the default location in a scene?
3. Use the Modify panel to set the height segments of the box to 6. Remember to always use the Modify panel, not the Create panel, to change an object.
4. The instruction in this step is wrong. Add an Edit Poly modifier to the box, not an "Editable Poly modifier". There is no such thing as an Editable Poly Modifier. Remember, when you add a modifier to an object, you can use the menu system or choose it from the Modifier List.
5. Step 5 says to press 4 on the keyboard to go to the Polygon sub-object mode. This did not work for me, but I was not disappointed. I think it is easier to use the visual cues in front of us than it is to remember hot keys like this. (4 stands for polygon mode? Why? Under what conditions?)
• Instead of pressing 4, click the Square icon for polygon sub-objects in the Selection rollout, as illustrated in the image above.
• If that is not mnemonic for you, open the Edit Poly object in the Modifier stack, and choose its Polygon sub-object.
6. Both actions accomplish the same thing.
After you have done this, click the polygon on top of the box, as instructed.
7. Step 6 is not wrong, but it is less clear than it might be. As I have pointed out above, you will see many unlabelled Settings buttons in 3DS Max. This time, you want to click the Settings button to the right of the Bevel button. This will open a dialog screen that you will use to add a series of bevels to the box.
8. Enter the Height and Outline Amount values given. Click Apply, which applies the action, but keeps the dialog box open.
9. Enter the Height and Outline Amount values given. Click Apply, which applies the action, but keeps the dialog box open.
10. Step 9 is confusing, because it contains the settings for five bevels. It might be good to write them all down so you don't miss any. Let's make a list, starting with the two you set back in steps 7 and 8.

Bevel Settings for Top of Chest
Step Height Amount Action
7 .5 1.3 Apply
8 .1 .06 Apply
9 .1 .03 Apply
9 .1 0 Apply
9 .3 0 Apply
9 .1 -.06 Apply
9 .1 -.08 OK

Enter the Height and Outline Amount values given. Click Apply, for each bevel layer until the last one, then click OK . Your work should look a lot like the illustration on page 144. Zoom and pan as needed to check it.

If anything goes wrong Undo is your friend. Remember the Undo button on the tool bar?

Project Exercise 2: Bottom of the dresser

Save your project before you begin this portion of it. (Yes, really. Do it now.)
You will need to relax and concentrate since the authors do not tell you how to do some things you will need to do. I'll try to help.

DISCLAIMER: The instructions below were written for 3DS Max 2009. The interface for 2010 is a bit different. If I tell you to right-click something, you may need to left-click instead in our newer version of the program. Proceed carefully, and make notes for yourself for reference.

1. In step 1, the authors tell you to select the polygon on the bottom of the box. They do not tell you how to get a view like the one shown on page 145. For this step, you just need to see the bottom of the chest. Right-click the Left viewport to select it. Right-click that viewport's name and select Bottom. (This in one of the differences noted above. In the 2010 interface, you just left-click the viewport name and choose the new view.) Use Pan and Zoom controls, if needed, to get a nice view. After you change a view with Pan (and sometimes, Zoom), you will have to click the tool you need to use in order to continue working.
2. Make sure the polygon sub-object is selected on the Selection rollout of the Modify panel. If it is not open, open the Edit Polygon rollout.

Note: the authors tend to write "poly" even if the screen says "polygon". This is not helpful to me, nor to you, I suspect. Let's be aware of it and recall that this is what they do.

Click the Settings button to the right of the Extrude button on the Edit Polygon rollout. This time you have one action to perform, so set the Height to 2.5 and click OK. As the text notes, a new segment is added to the box.
3. The polygon you just extruded should be the only one selected. If not, select only that one. Click the Settings button for the Inset button on the Edit Polygon rollout. Set the Amount to .6 as instructed and click OK. The polygon will appear to shrink.
4. Click the Settings button for the Extrude button again. Set the Height value to -2.0, which will cause the polygon to move toward the top of the chest.

This is a good place to pause and save again. Remember to save your file with a new, incremental name, so you have more than one place to go when you need to go back in time.

Project Exercise 3: Bottom detail

The text starts a new set of steps on page 149 to carve away sections of the extruded material, so the model will look more like the chest detail on page 146. To do this, you will need to be able to rotate the model in space, and you will need to be able to select and deselect separate polygons in the model.

Standard Windows skills will help: when you want to select more than one thing, hold down a Ctrl key while you click each new item. When you want to deselect an item already selected, use Ctrl-click for that as well.

Go back to chapter 3 for a moment, and look at the last three icons illustrated on page 85.

• Arc Rotate - gives you a gizmo to rotate the current viewport around the center of the viewport
• Arc Rotate Selected - gives you a gizmo to rotate the current viewport around the currently selected object
• Arc Rotate Subobject - gives you a gizmo to rotate the current viewport around the currently selected sub-object

These tools will give you a way to spin the viewport around so you can see whatever you need to see in the following steps. (If you are using 3DS Max 2008 or later, you can also use the gizmo built into each viewport.) You will also want to use pan and zoom functions. Again, when you switch away from a tool to use rotate, pan, or zoom, you will have to switch back to that tool to use it again. This will become clear as you work on this exercise.

1. Step1 on page 149 tells you to select all the polygons that make up the front and back lip on the bottom of the chest. Look at the illustration on page 149.

Think of the bottom of the chest as being constructed of four boards. For reference, let's call the boards the front, back, left, and right baseboards of the chest.

You want to select six polygons at this stage. They are the front, back, and bottom polygons of the front and back baseboards. You can see that the front and bottom polygons of the front and back boards in the picture have already been selected. You do not have to select the top polygons of the baseboards, because they do not need to be cut. That is because you will be collapsing surfaces, not actually removing them.

The trick to make this work is to rotate the chest so that you can select all six polygons, and only those six polygons, in the same selection set. Why do you have to rotate the chest? You have to be able to see a polygon to select it, and you must not click it in a way that will deselect another polygon that you want selected as well.

This is not a minor acrobatic skill. You will have to practice this action to get it right. I recommend that you save incrementally when all six polygons are properly selected (or maybe even sooner). Also, follow the instruction at the end of step 1 to lock the selection with the Lock button near the center of the bottom of the 3DS Max interface.
2. Now that you have performed your first miracle, follow the instructions in step 2 to set up the Slice Plane tool. You will use this to make a series of cuts in the selected polygons. The great thing about the tool is that it will not cut any polygon that is not selected. That could also be a problem if you have not selected everything you want to cut.
3. Turn off Shaded Edge mode as instructed by pressing F2. As the text explains, you need to do this so you can see the new edges that you will cut in the existing polygons. If the polygons were still red on their selected faces, you would not see the new lines you are about to make.
4. In step 4, make sure you have selected the Slice Plane tool before you right-click it to show its quad menu. Go to the Transforms section of the quad menu and click Rotate.
5. Step 5 tells you to rotate the Slice Plane tool on its y-axis. As you may have noticed, it is very difficult to rotate an exact number of degrees by dragging a gizmo. Use the Transform type-in box instead to change the y-axis value to 90. (There is a type-in box for each axis.)
6. Click the Move tool on the tool bar, which will affect the Slice Plane tool. You want to make cuts at several spots on the six polygons that are selected. I will suggest that you should use the Transform type-in box again, this time using the box for the x-axis. For the cuts in this step, change the x-axis value to -12 before the first cut, then to 12 for the second cut. As noted in the text, make the cuts with the Slice button, not the Slice Plane button, which would turn off the cutter.
7. In step 7, you make more cuts. Use the method I described above to move the Slice Plane tool for each of these cuts:

Cuts to Make in Step 7
X-axis transform Action
-11.5 Slice
11.5 Slice
-11 Slice
11 Slice
-10.5 Slice
10.5 Slice

You could make cuts at different locations, but they should be symmetrical from one side to the other, or the chest will not look very good. I have color coded the rows above to make it clear that the cuts are being made in pairs. I will point out, as well, that you are cutting the front and back baseboards of the chest at the same time.
8. In step 8, the text says to press the spacebar to unlock the selected polygon set. This did not work when I tried it, so I will point out that you should click the padlock icon to unlock the selection set instead. When you do so, the highlight behind the padlock icon will go away.
The text continues, telling you to select the "relevant polygons" and use the Move tool to approach the scalloped effect seen on page 153. By relevant polygons, they mean the ones along the bottom of the boards you cut, so selecting them from the Bottom viewport would be fine. You may want to experiment with this step. As should be instinctive by now, save first.
Question 8: Describe the method you used to scallop the front and back baseboards of the chest, starting are step 8.

The authors instruct us at the end of step 8 to repeat these steps as needed to scallop the right and left baseboards of the chest as well. Let's leave that for another assignment and move on the the drawers.

Project Exercise 4: Drawers

Again, examine the reference material for this step. A detail photo of the reference chest appears on page 154.

1. Step 1 begins with a statement that sounds like an instruction. It is not. The authors are telling you their plan for several steps: to make a gap around the drawers. This is not actually a gap. It represents the edges of the side, top, and bottom boards of the chest. Start this exercise in the Front or Perspective viewport. Select the six polygons that represent the drawers of the chest as instructed.
2. Open the Modify panel, Edit Polygons rollout. Click the Settings Button beside the Inset button. Set the Amount to .6 as indicated. This time, it is important to make sure that Group is selected for Inset Type, because you want the entire set of six drawers inset as one group, with one ring running around them all.
3. Step 3 seems to think that the drawers will look more natural if they are extruded into the chest slightly. This is why the Extrusion Height value used is a negative number (into the object): -.5.
4. Step 4 tells us that you are going split the top drawer into two drawers. This matches the reference. The text cautions you to press F2 if needed, so that the selected polygons are shown as red outlines instead of solid red. You are doing this for the same reason you did it in the cutting exercise above.
5. Select the polygon for the face of the top drawer. You will not have to cut any other polygons for this drawer, since the drawers in this model will not move.
Select the Slice Plane tool again. You will probably see it appear right where you left it. If not, rotate it as needed and move it into place to cut the selected polygon into two pieces, as indicated in the illustration on page 157. Click Slice to make the cut, and click Slice Plane to turn off the tool.
6. In step 6, you apply an Inset to the two new polygons (they were one), as instructed. Make the Inset Amount .25, and this time, make sure to select By Polygon for the Inset Type value. The text says to compare your work to the image in figure 4.64. At this stage, it should look more like the image at the top of page 159.
7. Repeat the instructions in step 6, this time for each of the remaining drawers in the chest.
8. In step 3, you extruded all the drawers into the chest. This was really for the supporting wood around the drawers. Now, select all of the drawer polygons on the front of the chest. Click the Settings button to the right of the Extrude button on the Edit Polygons rollout. Make the Extrusion Amount .7, and make the Extrusion Type By Polygon. This will move each of the drawers a bit out from the front of the chest.

Save again. There is only one exercise left, but it seems to have been broken into three. Get ready to learn more new skills.

Project Exercise 5: Creating knobs

Page 167 shows a reference image of a knob that is like the ones you want to put on the model. The text introduces you to several skills needed to create such a knob.

1. Step 1 reminds you to place the knobs on the drawers. To that end, you are told to start in the Left viewport, where you can draw an outline for a knob. If you look carefully at the picture on page 162, you will see that you only have to draw half of the knob. The half drawing will be rotated with the Lathe tool to generate a 3D shape from your 2D drawing.
2. On the Create panel, choose Shapes, Line. (You will draw a spline outline for the knob.) Note that the authors want you to set the Drag Type for your line as Bezier. This is a kind of control point for a line that lets you affect how the line curves into and out of that point.
3. Back in the viewport, you will click along an imagined line, similar to the pattern on page 163. It may be easier to pan and zoom first, to give yourself enough room to work. Also, remember that you can maximize the current viewport by pressing Alt-W. (It does not really matter if you draw the knob attached to the drawer, since you can move and rotate it once it has been created.)
4. Step 4 tells you that you can either:
• make the spline a closed figure (as shown on page 163) by clicking your first point again, or
• you can leave the spline as an open figure by making your last click anywhere short of the first point, and right-clicking to end the spline creation
The authors tell you that you can edit the curve of your spline, but they do not tell you how. As I mentioned above, bezier points are used to affect the way the line curves. You should save, then experiment with this idea.
5. In the modifier stack for the project, find the object for your line, and open it as instructed on page 163. Note the sub-objects listed: vertex, segment, and spline.

For some reason, the authors break from the exercise here and start a new series of numbered steps. This seems unnecessary. Assume that step 1 below follows step 5 just above.

1. Choose the vertex sub-object. Click the Select and Move tool, and use it to move a vertex in a direction that will make the line more like the reference image.
2. When the line is acceptable, select the line object again. Then, add the Lathe modifier by either of the two methods described on page 165.
3. The text is convinced that you can adjust the resulting shape of the Lathed line by clicking Max or Min button on the Align section of the Parameters rollout. You may find that it is more useful to click the axis buttons under the Direction section to control which axis the Lathe rotates the line around.
4. Use the Weld Core option to remove the extra vertices that were caused by Lathe rotation.

Finally, the last page in this part of the chapter. The text realizes that you must make copies of your knob, so instructions are on page 166. 3DS Max can do three kinds of copying, but the generic term it uses is not "copy", it's "clone".

1. Use the Move and Rotate tools as needed to place the knob on one of the top drawers. (If the knob is too big, you may need to check the Help system for information about using the Scale tool.)
2. With the only knob selected, start the clone procedure by clicking the menu option Edit, Clone. There are three choices in the clone dialog box that produce different results:
• copy - copies of an object are independent of each other and independent of the original object
• instance - instances are linked objects; changing one instance will affect all other linked instances
• reference - reference objects link down: you can change the base object (the original one) and affect all the references, or you can change just a reference, affecting none of the other references or the original

This time, the text says to make instance clones.
3. Position the new instance in the correct place on the other top drawer.
4. Follow the directions to make the rest of the knobs. I will show you a better way in class.

Save your project again and show me the sequence of saves on your computer.