Bonus Ch. 1. Subdivisional Modeling. Understanding Sub-Ds

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1 Bonus Ch. 1 Subdivisional Modeling Throughout this book, you ve used the modo toolset to create various objects. Some objects included the use of subdivisional surfaces, and some did not. But I ve yet to fully explain the workflow of subdivisional surfaces, what they are, and how they work. When you model an object, even just a ball or a cube, you re creating polygons. Polygons have faces, or surface normals. When you press the Tab key in modo, you turn an ordinary face polygon into a subdivided (subdivisional) surface. The polygons become smooth when converted to subdivisional surfaces, also known as sub-d s. You might have heard the term NURBS (non-uniform rational b-splines ), introduced by Edwin Catmull, Jim Clark, Daniel Doo, and Malcom Sabin in This method was made popular in 1995 by Ulrich Reif. But this book is not intended to be a lesson in programming history, nor is it designed to explain the mathematical calculations that make up a sub-d surface. The goal of this chapter is to teach you how to model in sub-d mode. Understanding Sub-Ds Sub-d s are an excellent choice for modeling characters because you can create a significant amount of detail without a lot of geometry. Why is this, you ask? Good question! You see, a subdivisional polygon is dynamically multiplied. It is refined to as much detail as you specify. In fact, modo 201/202 offers you the ability to have micropolygon displacement, which, when combined with subdivisional surfaces, allows you to create models with the utmost physical detail. Subdivisional surfaces are not only great for characters, but for anything you can think of.

2 2 The Official Luxology modo Guide There are a few things you should be aware of before you begin modeling a character with sub-d s. The most important aspect is the flow of the geometry. The flow is the way the polygons in the mesh are aligned. For example, Figure B1.1 shows the modo old man model with good flow. Figure B1.2 shows the same model with bad flow. Figure B1.1 Using the old man model from the modo content directory, you can see that the polygons in the mesh flow nicely, and the geometry is smooth and even. Figure B1.2 Using a variation of the old man model from the modo content directory, you can see that the polygons in this mesh don t flow properly, resulting in a model that isn t as smooth as it could be. This can also result in shading and rendering problems. Proper flow of your subdivisional surface model is important to understand before you begin modeling. This way, you ll not only have more control over what you re building, but you ll have better results when rendering. With that said, how about seeing it in action?

3 Bonus Chapter 1 Subdivisional Modeling 3 Building a Character in Sub-Ds To begin creating this character, you ll use a primitive shape. There are a few methods to model characters, and in fact there has been an ongoing debate among 3D content creators as to which method is best. This book is going to blow the doors off that myth by now declaring the best method. First you have the box modeling method, in which you start with a box and subdivide your model into shape, similar to an artist creating a beautiful sculpture out of ice. Another method is the point-by-point method, in which you build your geometry one point at a time using a background image. This is great for modeling characters from sketches or photographs. A third method is spline-based modeling. Splines are curves that you can align, and then patch together to make a model. Which method is best? None of them! That s right now you can rest easy because the debate is over. The point is, no one method is best for everything, be it modeling, surfacing, or rendering. It s completely up to you and what method you re comfortable using. The character in this chapter will benefit from simple geometric shapes, often known as the box-modeling method. Figure B1.3 shows a cube created by holding the Shift key and clicking the Cube primitive button. Next to it is the same cube after pressing the d key, which subdivides the cube. The image on the right shows the same cube subdivided one additional time. Figure B1.3 By starting with a simple cube, and then pressing the d key two times, you can see how this basic shape becomes subdivided. Looking more closely at Figure B1.3, the third image of the cube is the most subdivided, although if you look at the edges of the model, it s still rough. Pressing the d key only subdivided the mesh, it did not turn it into a sub-d model (a subdivisional surface). It sounds confusing, but if you take a look at Figure B1.4, the image on the left is a subdivided cube, whereas the image on the right is a subdivisional surface. This subdivisional surface was created by pressing the Tab key. Figure B1.4 While subdividing the mesh, you can see that the image on the left is chunky. By pressing the Tab key and activating sub-d mode, the image on the right is smooth.

4 4 The Official Luxology modo Guide Note Pressing just the d key creates a subdivisional surfaces subdivision (SDS). If you press Shift+D, you can choose between a Faceted (flat), Smooth, or SDS subdivision. Starting with a Cube for the Head As you begin modeling this character, you ll use simple geometry, subdivide as needed, and convert the mesh to sub-d s along the way. 1. Start modo 201/202 and go to the Tool Bar tab. 2. Holding the Shift key, click the Cube primitive. This will create a perfectly shaped cube and put it into its own layer in the Item List. 3. Press the d key two times. Figure B1.5 shows the model. Exciting, isn t it? 4. Jump to Edges selection mode at the top of the modo interface. While the shape of the subdivided cube is a good starting point, it can be better. Select the middle edges on the X, Y, and Z of the subdivided cube. Simply double-click one, then hold the Shift key and double-click the others. Figure B1.6 shows the selections. 5. Once these center edge loops are selected, press the Backspace key on your keyboard to remove them. Figure B1.7 shows the cube after the edges are removed. 6. Now select the two edge loops on the Z axis, as shown in Figure B With these two edges selected, press the r key, grab the red handle, and stretch these edges down to 60%, as shown in Figure B1.9. Figure B1.5 To begin building a sub-d character in modo 201/202, start with a Cube primitive, then perform an SDS (subdivision surface subdivide) by pressing the d key two times.

5 Bonus Chapter 1 Subdivisional Modeling 5 Figure B1.6 Select the center edge loops for the X, Y, and Z axes. Figure B1.7 Delete the center edges for the X, Y, and Z axes. The model should look something like this. Figure B1.8 On the Z axis, select the two edge loops. After you select one loop, hold the Shift key to click and select the next. Figure B1.9 Bring the two remaining edges in by selecting them and stretching them on the X axis.

6 6 The Official Luxology modo Guide 8. Normally, you have to now deselect the edges, turn off the Stretch3D tool, reselect the next set of edges, and turn the tool back on again. The modo team realized you work this way and added a feature that can help. Over in the Tool Pipe tab on the bottom-right of the modo interface, right-click on the Stretch listing in the Tool Pipe. At the bottom of the pop-up, choose Select Through, as shown in Figure B Hold the Ctrl key, and then, with the middle mouse button, lasso-select the two selected edge loops. Select Through allows you to keep a tool on and only worry about your selections. Select Through replaces the ability to haul in the viewport, so don t turn off the Stretch3D tool; rather, double-click on the edge loop on the X axis, and also select the second edge loop by holding the Shift key and adding to the selection. 10. Then, grab the blue handle to stretch these two selected edges in on the Z axis, as shown in Figure B1.11. Figure B1.10 Rather than turning off a tool, reselecting, then turning on the tool, use modo s Select Through feature from the Tool Pipe. Figure B1.11 Stretch the side edges of the subdivided cube in on the Z axis.

7 Bonus Chapter 1 Subdivisional Modeling Now repeat the last few steps for the edge loops around the Y axis, and stretch those in. When all of the edge loops are evenly spaced, turn off the Stretch3D command, deselect any remaining edges, and then press the Tab key. Figure B1.12 shows the new subdivided cube with six fewer edges. This setup will give you a much better working mesh for a character, as you ll see momentarily. Building the Neck Once the subdivided cube has had its edges adjusted, it s time to first save your work, then begin shaping out the neck of the character. Remember, this is a freeform method, but this technique can be used for a cartoonish character, a caricature style, or a realistic human. The difference is in the details. 1. Select the six polygons that make up the bottom back of the cube, as shown in Figure B Press b for bevel, and then click in the viewport to activate the tool. Make sure that Group Polygons is checked on in the Tool Properties panel. Grab the blue handle and drag it down to set the Shift value to about 33cm. Figure B1.14 shows the operation. Figure B1.12 Once the edges are all positioned evenly using the Stretch3D tool, sub-d s are activated by pressing the Tab key. Figure B1.13 Select the bottom six polygons that make up what will become the top of the neck.

8 8 The Official Luxology modo Guide Figure B1.14 Bevel the neck out from the six selected polygons. 3. You ll shape the neck in a little bit. For now, save your work and deselect the neck polygons. Then, from the top of the modo interface, turn on Symmetry and set it to X. Everything you do from this point on the positive X axis will be mirrored on the negative (left) X axis. This works because the cube you made in the very beginning of the project was created automatically by modo, which not only gave it a layer name, but it also made it perfectly centered in the viewport. 4. Then, press the t key to activate the Element Move tool. Click and drag the right edge of the chin down and in a bit, as shown in Figure B1.15. The movement on the right side will be mirrored on the left. If it s not, you ve somehow made the sides of the model uneven. To fix this, you can center the object from the Tool Bar tab, but only after you ve turned Symmetry off. When you have it centered, turn Symmetry back on and try again. 5. Still using the Element Move tool t key, click and drag a large polygon on the right side of the face. You might want to rotate the view around to see a little more of the side of the head. Drag the polygon forward to begin creating the cheeks of the character.

9 Bonus Chapter 1 Subdivisional Modeling 9 Note There are times when Symmetry just won t work because you ve made too many adjustments to your mesh. And if that happens, going back by clicking Undo actually undoes a lot of good work. If this is the case, just repeat the steps on the other side of the model, or in some cases, select those edges and/or polygons and perform the operation at the same time. Conversely, you can cut away one half of the model and build just one side of the head. When you are finished, you can mirror it over to complete the full head. The choice is yours. Some people like to work this way, while others like to see the full model coming together, hence the use of Symmetry. Figure B1.15 Using the Element Move tool, pull the edge for the chin down to shape. 6. Now, using the Element Move tool, click and drag on the polygons around the top of the head to round it out. Figure B1.16 shows the example. 7. Continue using Element Move to shape the head to a nice, rounded egg shape. Remember that with Element Move you can click on vertices, edges, or polygons. Remember to hold the Alt key and rotate around the viewport, shaping as you go. 8. Using Element Move, tighten up the neck. You might find that it s a little hard to manipulate, even just sizing in the edges. Figure B1.16 Shape the head using the Element Move tool. Round it out to a smooth egg-type shape.

10 10 The Official Luxology modo Guide 9. The neck might need a little more geometry to obtain a good shape. So, select two polygons on the front of the neck, then press Alt+c to call up the Loop Slice command. Click and drag, and you ll slice the neck. Sounds painful! Make sure the Count is set to 2, as shown in Figure B1.17. Figure B1.17 Using the Loop Slice tool, you can add a little more geometry to the neck. 10. Double-click the edge around the middle of the neck. This is the top edge of the two you just created with the Loop Slice command. Press the r key for Stretch3D, click on the light-blue square in the center, and drag. Notice something? The X axis isn t scaling down. This is because you still have Symmetry active on the X from the top of the modo interface. 11. If you disable Symmetry, you can scale the neck evenly. When finished, it s a good idea to put Symmetry back on. Figure B1.18 shows the first Stretch3D operation. Figure B1.19 shows the neck edge now stretched down evenly, using the Stretch3D command. Note that Automatic Action Center is also enabled. 12. You ll finish off the neck a bit later. For now, go to Polygons selection mode and select the two polygons that make up the top-front center of the head, as shown in Figure B1.20.

11 Bonus Chapter 1 Subdivisional Modeling 11 Figure B1.18 Because Symmetry is still on for the X axis, the Stretch3D command doesn t function properly on that axis. Figure B1.19 With Symmetry off, you can easily and evenly scale down a selected edge. Figure B1.20 Select the two polygons that make up the front top of the face. 13. Press b for bevel and bevel the two polygons, making sure Group Polygons is turned on in the Tool Properties panel. Set the Inset to 1cm and Shift to 10mm. This can vary based on your taste, of course. 14. If you look at the flow of the geometry around the top front of the head, it s not that smooth. This is where the proper polygonal flow is important to address. With Symmetry turned on for the X axis, select the two polygons that make up the area just to the right of the nose, into the eye position, as shown in Figure B1.21. Figure B1.21 Select the two polygons to the right of the nose, with Symmetry on the X active.

12 12 The Official Luxology modo Guide Note Depending on how your modeling tasks are coming along, you might have inadvertantly offset a portion of the geometry from the X axis, resulting in the loss of Symmetry function. If this happens, you can always work on both sides of the head at the same time. 15. With the two-polygon area selected off of the center nose area, you should have four total polygons selected with Symmetry active. Go to the Geometry drop-down menu at the top of the modo interface. Go down to the Polygon category, and then select Spin Quads. This will rotate the selected polygons, changing the flow of the geometry, as shown in Figure B Deselect any selected polygons. Save your work. 17. Press the t key for Element Move, and sharpen up the nose to look something like Figure B Select the three polygons that make up the front of the mouth area, and then bevel these down about 14cm or so. After the bevel, select Move (the w key) and bring the polygons up to even their position with the rest of the face. You might need to bring the newly beveled polygons forward on the Z axis as well. Figure B1.24 shows the result. Remember to have Group Polygons active in the Tool Properties panel for Bevel. Figure B1.22 Using the Spin Quads feature, you can rotate polygons made up of four vertices to change the overall flow of the model. Figure B1.23 Using the Element Move tool, you can tighten up the area around the nose and shape it.

13 Bonus Chapter 1 Subdivisional Modeling Select the center polygons from the bottom of the nose down to the neck, as shown in Figure B1.25. Figure B1.24 Select the three polygons that make up the area around the mouth, and then bevel. Figure B1.25 Select the polygons from the bottom of the nose down to the neck. 20. Bevel these selected polygons with Group Polygons turned on in the Tool Properties panel for Bevel. Bevel the Inset to about 2cm and the Shift to 1cm. 21. Turn off the Bevel tool, and then deselect the polygons. Then, using the Element Move tool, click and drag the edges around the nose and mouth to smooth out their shape. You want even spaces between the edges, and make sure to pay attention to the overall flow of the model. If something doesn t look right to you, press t again for Element Move, then click and drag on the vertex, edge, or polygon to adjust. 22. Next select the polygons that make up the mouth area. Bevel them down slightly about 1.5cm or so, something like you see in Figure B Deselect the mouth polygons. You ll come back to these for the details later on. Now, move up to the eye areas. Press t for the Element Move tool, and drag the edge that makes up the bridge of the nose down about 2mm on the Y axis, as shown in Figure B You can also use the Element Move tool to click and drag vertices to shape the bridge of the nose as needed. Then, with Symmetry on the X axis active, select the two polygons that make up the eye area, as shown in Figure B1.28.

14 14 The Official Luxology modo Guide Figure B1.26 Select the polygons that make up the mouth area and bevel them. Figure B1.27 Drag the edge that makes up the bridge of the nose down a bit. Figure B1.28 Select the two polygons that make up the eye area. Turn Symmetry on for the X axis to mirror the operations on the negative X axis. 25. Press b and bevel the selected polygons slightly. The goal of using bevel here is to simply multiply the polygons. 26. Again, using the Element Move tool, click and drag the center edge of the eye areas back into the head. Do this from a Side view to help you judge your distance. Figure B1.29 shows the example. 27. At this point, save your work. Then, using the Element Move tool, go around the model and tweak the overall shape. Remember to hold the Alt key on your keyboard, then click and drag in the viewport to rotate. Click and drag on any elements, vertices, edges, or polygons to adjust. Figure B1.30 shows a more rounded nose at the tip. 28. Then, go back to the mouth area, select the polygons in the center of the mouth, then bevel them down about 3cm or so. Figure B1.31 shows the result. 29. Now, save your work. The steps here have given you a good introduction to getting started with subdivisional surfaces when it comes to modeling a character. But this is only the beginning, as you can see. To really get a good idea of how this process works, check out the character modeling video tutorials on the book s disc.

15 Bonus Chapter 1 Subdivisional Modeling 15 Figure B1.29 Drag the eye area into the head to create an eye socket. Figure B1.30 Drag elements around the nose to round it out. Figure B1.31 Bevel in the mouth area to create more detail.

16 16 The Official Luxology modo Guide What s Next Subdivision surface modeling is very powerful, and you ll see that even more in the videos that accompany this chapter. In this chapter, you ve easily created the beginnings of a character, all from a subdivided cube. Did you happen to notice how smooth the mesh looked even when moving edges or vertices with the Element Move tool? You didn t have to worry about polygon holes, polygons flipping over themselves, and more. The subdivisional surface enables you to work with smooth, flowing geometry. When you needed more detail, you simply selected the desired polygons and beveled to add more detail. The same can be done for edges too. It s highly recommended that you watch the videos that accompany this chapter. One reason the instructions don t take you further in print is that the concepts are much better explained in video form. Once you understand this process and have created a character of your own, move on to the next chapter. Here, you ll use a combination of subdivisional surfaces and hard surfaces to create a cool toy gun model. The model techniques and details you ll learn can be applied to almost anything, from cars to spaceships.