Essential LightWave 3D- P12

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Essential LightWave 3D- P12

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Essential LightWave 3D- P12: What you have in your hands is, quite simply, a collection of tools and techniques that many professional LightWave artists use every single day doing what we do in our various fields. The tools and techniques explored in this book are essential to creating the caliber of imagery that you see on film and television and in print and video games.

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  1. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · placed straight down from the corner of Spin your model around in the Perspective the mouth (when looking in the Back viewport and check for anything that looks viewport) and centered between the out of place. first point and the last point of the We’ve expanded our spline cage, but the spline created in Step 28. Create a new area around the mouth is still open. Let’s spline. This will act as the bottom of close that off. Considering that we already our quad cage. have a top spline (created in Step 20), it makes sense that we should create splines Since we now have top, right, and bottom for the bottom, left, and right to complete a splines, we need to complete our quad cage quad cage. However, there’s no need to with a left spline. patch the region inside the mouth, and thus 30. In the Right viewport, create four new there’s no need for a left spline. You can points as shown in Figure 14-40. These create one if you like, but it won’t be used. should start at the lower lip and run Hence, we simply need splines for the right down the profile, ending at the center and bottom. of the chin. The points should be posi- 31. Create two new points as shown in Fig- tioned at the very center of the head in ure 14-41. Select all three points as the Back viewport. Select all of the shown and create a new spline. This points shown in the figure and create a will be the right side of our quad cage. new spline. Figure 14-40 318
  2. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d Figure 14-41: This small spline defines the corner of the mouth. Figure 14-42 32. Create two additional points as shown than the other regions in our cage, and the in Figure 14-42. Then select the points area around the jaw consists of more than shown and create a new spline. This four splines. We need to address each of will be the bottom of our quad cage. these issues. By adding these two splines, we’ve created 33. Select the existing points under the the inside boundaries for our face, but we’re nose and over the cheek as shown in now in violation of Tips 2 and 3. The area Figure 14-43 and create a new spline. over the nose and cheek is much larger (If you don’t have the points needed to 319
  3. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · create this spline, you can add them by 34. Create two more points as shown in selecting each spline and using the Figure 14-44. Select all of the points Multiply | Subdivide | Add Points shown and create a new spline. This tool.) This becomes the top spline of a becomes the right spline in our quad new quad cage. cage. Figure 14-43 Figure 14-44 320
  4. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d 35. Create two points along the bottom of We’ve partitioned off the area under the the lower lip as shown in Figure 14-45. nose and around the cheek, but it wouldn’t Select all of the points shown and cre- hurt to break the entire area into smaller ate a new spline. This becomes the sections. bottom spline in our quad cage. And 36. Create a single point at the top of the since the profile spline already exists, it nostril where it indents and joins the will act as the left spline, completing tip of the nose. Then select the exist- the quad cage for this area. ing points as shown in Figure 14-46 and create a new spline. This becomes the top of a new quad cage. You’ll notice that this new spline is not evenly spaced between those around it. As a result, we have created a nar- row region running over the tip of the nose and down the side of the face. This narrow region violates Tip #3, but the tightly spaced polygons we’ll get by patching this region are Figure 14-45 necessary to properly define the muzzle region of the face. Figure 14-46 321
  5. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · 37. Create two more points radiating out 38. Create two more points below the from the corner of the mouth as seen in lower lip as shown in Figure 14-48, Figure 14-47. Select all of the points then select all of the points in order, and create a new spline. This becomes and create a new spline. This becomes the right side of our quad cage. the bottom spline in our quad cage. Once again, with the profile spline act- ing as the left spline, this completes our quad cage. Figure 14-47 Figure 14-48 322
  6. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d If you haven’t done so recently, now would (specifically around the jaw and chin areas), be a good time to spin your model and so we must partition these to create a quad check for anything that looks out of place. It cage. would also be a good time to save your Looking at Figure 14-49, we can see that model. two distinct edge loops converge at the jaw. You can really see the face starting to We need to section off the jaw so that each take shape! But we still have areas that of these loops can continue along its own consist of more than four splines distinct path. Figure 14-49: Two edge loops converge at the jaw, requiring us to divide the area with a new spline. Figure 14-50 323
  7. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · 39. Create three new points that follow the the cage, two things are pretty clear. First, jaw line as shown in Figure 14-50. we’re almost done with the face. And sec- Select each of the highlighted points ond, we’re violating Tip #3. Although the shown in the figure and create a new jaw now consists of a quad cage (where spline. You can see that each loop from each region is bounded by four separate Figure 14-49 now has its own path to splines), the areas to be patched are much follow. larger than those around them. We’ll finish the face by partitioning these areas. Spin your model and check for anything that appears to be out of place. Looking at 40. Select the existing points shown in Fig- ure 14-51 and create a new spline. Figure 14-51 Figure 14-52 324
  8. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d Figure 14-53 41. Select the existing points shown in Fig- Take a look at Figure 14-54. The head ure 14-52 and create a new spline. and neck can be broken down into one large 42. Select the existing points shown in Fig- quad cage. There are distinct top, bottom, ure 14-53 and create a new spline. left, and right sides. At this point, most of the left side and part of the top already have Zoom out and take a look at your spline splines in place. We simply need to com- cage, correcting anything that seems out of plete the remaining splines to form a quad place. The face is now complete. All that cage around the entire region. remains is to build splines for the back of the head and neck, but if you’ve made it this far, that will be a piece of cake. We can use the exist- ing cage as a starting point for building the remaining splines. But with no ending point to guide us, it’s difficult to determine where each spline should go. There- fore, we must develop a basic framework to help guide the placement of each new spline. This framework can be cre- ated from an outline of the head and neck. Figure 14-54 325
  9. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · 43. Create three more points at the center 44. Create five more points running down of the head that run over the top the back center of the head. Select all toward the back of the skull. Deselect of the points shown in Figure 14-56 and these points. Select the four points create a new spline. This becomes the shown in Figure 14-55 and create a right spline in our quad cage. new spline. This completes the top spline in our quad cage. Figure 14-55 Figure 14-56 326
  10. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d 45. Create six new points around the neck becomes the bottom spline in our quad running from the back to the front. cage. Then select all of the points as shown 46. Create a single point about halfway up in Figure 14-57 and create a new the center of the neck. Then select the spline. Make sure that you adjust the points shown in Figure 14-58 and cre- points for this spline in both the Back ate a new spline. This becomes the left and Right viewports to ensure that the spline, completing our quad cage. spline forms a semicircular shape. This Figure 14-57 Figure 14-58 327
  11. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · Having completed the framework, we can points on the back of the head. As a result, wrap up our spline cage by playing “connect we’re going to use a different technique for the dots.” The existing splines on the face building these splines. end at an edge loop that runs over the fore- 47. Select the two points shown in Figure head, down the side of the head, and under 14-60 and press + to the chin. Each of these splines can be con- create a new spline. nected to the framework created in Steps 43 through 46. (See Figure 14-59.) I mentioned at the beginning of this tutorial that the most basic spline consists of three points. Two act as endpoints, and the third acts as a control point that allows you to adjust the shape. We’ve just created a two-point spline which, if you examine carefully, is perfectly straight. It needs a third control point to alter its shape. 48. Switch to Polygon Select mode. The spline you just created should be high- lighted. Navigate to the Multiply | Subdivide menu and select the Add Points tool. Click on the center of the spline to add a third point. Then use the Drag tool ( + ) to adjust the shape of the spline. Make sure you rotate your object in the Per- spective view to check the shape of Figure 14-59: The remaining splines can be created by connecting those in the face to this new spline. (See Figure 14-61.) those outlining the head and neck. We could build each of these splines as we’ve done in the past by cre- ating “in-between” points, then selecting the points in order and pressing + . However, our spline cage has become fairly complex and this will make it difficult to position the in-between Figure 14-60 328
  12. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d Figure 14-61: Add a third point to this spline and adjust its shape using the Drag tool. 49. Continue connecting the dots and add- Note ing control points to create four more You probably noticed that the region we splines as shown in Figure 14-63. Be defined in Steps 47 and 48 has only three sides (see Figure 14-62). Sometimes, no sure to check your model in the Per- matter how hard you try, it’s impossible to spective viewport after you shape each create a quad cage. This is one of those new spline. Remember that the back of times. In circumstances like this, you should the head is rounded at the top but do your best to position the three-sided cage in a part of the model that will rarely be tapers as it approaches the neck. Your seen (as we’ve done here). splines should reflect this. If you feel that you need additional control points to help maintain the shape of the splines, feel free to create them. (I’ve added extra points to two of the splines shown in Figure 14-63.) Figure 14-62 329
  13. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · Figure 14-63 Note At this point, we have another instance You’ll notice that we are skipping over the where two edge loops converge at a large ears at this point. Ears can be created with empty space. (See Figure 14-64.) We need splines, but the process of linking them into to partition this space just as we did before a larger spline cage can be tricky. As such, we’re following Tip #1 by using splines to so that each loop can continue on its own create the overall form. The detailed process path. of creating the ears will be covered in the final section of this chapter using traditional modeling tools. Figure 14-64: Two edge loops converge at the neck, requiring us to divide it with a new spline. 330
  14. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d 50. Select the two endpoints shown in Fig- We have a nearly perfect quad cage, but the ure 14-65 and create a new spline. back of the head and the neck are com- Then use the Add Points tool to add a prised of areas that are much larger than central control point. Use the Drag tool the rest of our cage. We must not forget Tip in the Back viewport to move this point #3! These areas should be divided into to the left slightly, creating a subtle arc smaller sections so that the same patch set- in the neck. tings can be used on the entire model. Figure 14-65 Figure 14-66: Keeping Tip #3 in mind, we must section off these large areas by creating a new spline. 331
  15. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · 51. Select the existing points shown in Fig- 53. The last thing we need to do is section ure 14-66 and create a new spline off the neck so that its surface area is running down the back of the head. not so large. Select the existing points 52. Create the three remaining splines shown in Figure 14-68 and create a shown in Figure 14-67 using the tech- new spline. niques you learned earlier. Figure 14-67 Figure 14-68: Divide the neck area into two halves with this new spline. 332
  16. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d Spin your model around in the Perspective The image on the left shows two splines viewport and move any points that seem that follow the same path from the top of out of place. If you feel that you need more the eye to the back of the head. At the point control over your splines, you can add where these splines meet, there is a sharp points to help adjust their shape. When dip. This dip isn’t a major problem and you’re finished, save a new version of your won’t affect our ability to patch this region, model. but it will have a subtle effect on the overall shape of our model. As such, it’s a good idea Before we wrap up this section, there are to merge these splines together. two more things we should do. With the two splines selected, press The first is to run a Merge Points opera- tion on our model. As I mentioned earlier, to merge them into a single spline. the number one cause of the “Curves Do The image on the right of Figure 14-69 Not Cross” error is splines whose points shows the effect of merging these splines are not welded together. By running a together. Note that the slope is now much Merge Points operation, we can ensure that more gradual. any stray points are fused together and pre- You can continue working through your emptively ward off this infamous error spline cage at this point, merging splines message. which, like those mentioned above, follow the same basic path but meet at sharp Press the key to bring up the angles. The splines highlighted in Figure Merge Points window. Accept the default 14-70 are just a few of the ones I would rec- settings and press OK. ommend merging. The second thing we should do is merge a few of these splines. Take a look at Figure 14-69. Figure 14-69 333
  17. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · Figure 14-70: Merge these splines to refine their overall shape. Note Note Merging splines can be beneficial to the At this point, I recommend saving your overall shape of your cage, but it can also object with a name such as “Generic Spline be detrimental if taken too far and can ulti- Head Cage.” One of the great things about mately affect your ability to patch the cage. modeling with splines is that a basic cage For example, merging the profile splines can be used over and over to create similar that run from the front of the head to the objects. In this case, a variety of head mod- back will cause havoc when you try to patch els can be created from this one basic cage. your cage. As you merge your splines, keep in mind Tip #2: Build quad cages. Try to keep the top, bottom, left, and right splines Congratulations!! Using the tips and tricks distinct from one another. Merging a Top outlined earlier in this chapter, you’ve built spline with a right or left spline could have a very complex spline cage. This cage is not adverse effects. If you find that you are get- ting erroneous patches (or patches that only efficient, but it has exceptional flow — don’t fit the area you’re attempting to fill), one of the most crucial factors of a good try splitting large splines into two or more head model. parts. You can do this by selecting the spline, then switching to Points mode, selecting the point where you’d like the split to occur, and pressing + . 334
  18. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d Figure 14-71: The cage we’ve just built can be quickly modified to create other head models. Later in this chapter, we’ll patch the cage object with a new name and let’s begin by and modify the results to ensure optimal learning about patching. poly count. When you’re ready, save your Patching Tips and Tricks We’ve done a lot of work to get to this • Tip 1: Patch in the Perspective point, but this is where our initial invest- viewport. Trying to select splines in one of ment really pays off. Under normal the orthographic viewports can be cumber- circumstances, patching our cage would some. To make your life easier, I suggest involve the tedious and painful process of working directly in the Perspective determining how many perpendicular and viewport. Click the Maximize Viewport parallel divisions to use for each section of button to work full-screen within this view. our cage. No more! Since we’ve built a quad cage and partitioned it into similarly sized • Tip 2: Patch in Wireframe mode. As you patch your cage, each region will be segments, we can use the same patch set- filled with polygons. Unfortunately, Modeler tings for the whole object, making it a treats splines as polygons. If your view type relatively easy procedure. Easy, however, is set to one of the shaded views (i.e., does not mean foolproof. There are a num- Smooth Shade, Flat Shade, or even Tex- ber of problems that can plague the tured Wire), Modeler will attempt to select patching process. Therefore, before we get the polygons on top first and will skip over started, I’m going to share a few more tips the polygons on the bottom. As such, it can and tricks with you. be particularly difficult to select your 335
  19. Chapter 14 · · · · · · · · · · · · · · · · · · · · · · · splines, especially as you get further along whose points aren’t welded together prop- in the process. Therefore, I suggest work- erly. But sometimes it happens in spite of the ing in the Color Wireframe mode. When in fact that everything has been done correctly. I the wireframe modes, Modeler does not see questions like this posted online all the respect polygon order and will select every- time: “My points are welded but I’m still thing your mouse moves over, not just the getting the ‘Curves Do Not Cross’ error… polygons on top. What’s wrong?” I honestly don’t know. Sometimes Modeler is weird like that. But I • Tip 3: Use contrasting sketch colors. can tell you this: If you go back and select The biggest pitfall of working in one of the wireframe modes is that it can be difficult to your splines in a different order (even distinguish between your splines and your reverse order), it will often work. I’ve run polygons. To make this process easier, give into a number of cases where selecting top your spline cage one color and your polygon (1), left (2), bottom (3), and right (4) will wireframes another. To do this, go to the give me an error, but selecting in a different Detail menu and under the Polygons head- order, for example, left (2), bottom (3), right ing, click on the Sketch Color tool. From (4), and top (1), will work. I can’t explain it. the pop-up menu, select Black as the sketch I can only tell you that it works. It’s very color and click OK. Changing the sketch likely that you’ll be seeing the “Curves Do color here will cause our spline cage to be Not Cross” error when you patch your head black when viewed in the Color Wireframe model. If that happens, refer back to this mode. Now bring up the Display Properties tip. panel by pressing the keyboard short- • Tip 5: Don’t worry about spline selec- cut. On the Layout tab, change Default tion order. To get the normals of your Sketch Color to White. By changing the polygons facing out, you must select your default sketch color, we are telling Modeler splines in a counterclockwise order before to use white wireframes for all of our newly you patch them. But as we’ve seen in Tip created geometry. This division of color will #4, there may be times when this results in help us determine which polys are splines a “Curves Do Not Cross” error. Therefore, and which are patches when viewed in a don’t worry about the order in which you wireframe render style. select your splines. It’s easy to correct polygons whose normals are facing the • Tip 4: If At First You Don’t Succeed, wrong direction after the fact. For now, sim- Patch, Patch Again. The number one prob- lem that people run into when spline ply patch and have fun. modeling is the enigmatic “Curves Do Not Cross” error. Often this results from splines 336
  20. · · · · S p l i n e M o d e l i n g E xe r c i s e 2 : M o d e l i n g a H u m a n H e a d Patching the Cage Let’s begin patching the cage. Make sure that you’ve set your spline color to Black Note and your default sketch color to White as You can access the Make Spline Patch win- described in patching Tip #3. Then maxi- dow from the Construct | Patches | Patch menu item, but I recommend using the mize the Perspective viewport and change + keyboard shortcut as it will the view mode to Color Wireframe. Hit save you a good deal of time. to “fit all” so that our cage fills the screen as shown in Figure 14-72. You can begin anywhere you’d like, but 2. The default for a spline patch is 10 Per- the area around the eye is a nice place to pendicular and 10 Parallel divisions start. distributed over the Length of the splines. However, 10 is far too many for 1. Select four splines in a clockwise or the cage we’ve built. Change each of counterclockwise order and press these to 2. Leave the distribution set to + to bring up the Make its default (Length) and click OK. The Spline Patch window. Figure 14-72: We’re ready to begin patching! Figure 14-73: The proper patch settings. 337
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