Essential LightWave 3D- P8

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Essential LightWave 3D- P8: 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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Chapter 7 · · · · · · · · · · · · · · · · · · · · · · · · By default, LightWave viewports show a surface of the sub-patch. The sub-patch sub-patch’s: surface behaves a lot like stretchy, digital clay. • Cage — The “ghosted” representation Even so, you still may be inclined to of the poly that is defining the sub-patch. think, “It’s a neat gimmick, but what can it • Surface — What will actually be ren- really do for me?” The upshot of this real- dered in Layout. time application of Multiply | Subdivide | • Guide — A ghosted line drawn from More | Metaform Plus is that you can the surface to the point on the original poly model extremely dense meshes using a that “controls” (influences) it. very light polygon “cage,” and you can do it Not quite sure what all the fuss is about? with the tools with which you’re already Each of the points of the original poly familiar! exerts influence over how the subdivision Sub-patch surface models can have their surfacing algorithm creates the smooth resolution dialed up or dialed down, not just while you’re modeling but while you’re Figure 7-2 Figure 7-3 198
· · · · · · · · · · M o d e l i n g 3 : S u b - Pa t c h O r g a n i c M o d e l i n g animating as well! Under Layout’s Object things a little easier or to fix things when Properties window, you set the resolution my work shows me I’m lacking in the fore- at which your sub-patch model will be dis- sight department, but for the vast majority played and the resolution at which it will be of my character modeling, those five tools rendered. (In Figure 7-3, that’s a difference (always with a healthy helping of the Sym- of 24,064 polygons!) You can animate with a metry mode) are the main tools I use when very speedy, low-poly mesh and render with modeling organic models. the ultra-polished 27,072 poly mesh with- out having to change a single setting when Note it’s time to render! You can also use what you have sub- Now that I’ve got your attention, how do patched as a kind of quick, temporary you turn that sub-patch “blob” in Figure 7-2 “grouping” as you work. Leaving part of into the character in Figure 7-3? You use your model as sub-patches and part as faces as you work, you can quickly select what you the Smooth Shift, Bevel, Drag, Move, and want to work on through the SubPatches Rotate tools. and Faces headings in the Polygon Statistics That’s it? Yep. That’s basically it. There window. are a couple of other tools I use to make Smooth Shift Smooth Shift works with sub-patches just to what happened with the window mold- the same as it does with polys. (In truth, ings when we rail beveled them in the last you’re better off thinking of your sub-patch chapter). There is a quick and easy fix to not as some arcane, spline-based “mysti- this, though: Let Smooth Shift handle mak- cism” but as polys that just happen to be ing the new geometry, and you handle nice, soft, and “roundy” and are never con- shaping and sizing it. sidered “non-planar,” no matter how you Smooth Shift with an Offset of 0 and a push their points.) Max Smoothing Angle of 0º is the best way However, as nice as the real-time work- to work with sub-patches. A simple way to ings of Smooth Shift are with planar, do this is to activate the Smooth Shift tool polygonal faces, it often “splits” the mesh () and then click without moving your apart at its points with sub-patches (similar mouse. (You can also achieve the same Figure 7-4 199
Chapter 7 · · · · · · · · · · · · · · · · · · · · · · · · effect by using the Super Shift tool men- takes more than makes up for the headache tioned in Chapter 3.) After smooth shifting, of finding a half-buried, “dismembered” set position and shape the new geometry by of points much later on in your work, the hand. (It’s good to get in the habit of results of an erroneous Smooth Shift opera- smooth shifting your sub-patches with tion you didn’t catch.) these settings. The tiny bit of extra time it Figure 7-5 BandSaw The best characters are made up of loops When you have Enable Divide active in (or bands) of four-point polygons. The the BandSaw window, the tool not only BandSaw tool can be used to subdivide selects the band of polys (along the U or V), these loops into smaller bands. You can it also creates more segments in that think of it as knifing along the path created selected band with respect to the band by the band of the polygons. markers. You create and position these Figure 7-6 200
· · · · · · · · · · M o d e l i n g 3 : S u b - Pa t c h O r g a n i c M o d e l i n g markers in the white area of the interface, which represents the top and bottom of the band of polys that will be selected/cut. Note A good way to determine the path that BandSaw will take as it cuts through your polys is to use the Select Loop tool (dis- cussed in Chapter 3) first. • Add puts more of these band markers wherever you click your mouse in the Figure 7-7 white area. • Edit lets you click and drag the band to use its interface window. It “remembers” markers. the last settings you used with it and • Delete removes any band marker you applies them immediately when activating click on. the tool. (I’ve mapped this tool to a hot key • Value lets you enter a specific position and assigned it to my Quick-Tools menu (0 to 1) along the white area for the tab, so when I want to select a band of my selected band marker. mesh, I just tap its hot key and keep right • Uniform repositions the band markers on working!) you have, spreading them all out evenly. • Mirror creates a new band marker that Note mirrors your currently selected one. The Preset pop-up menu in the BandSaw Pro Numeric window will remember the settings • Reverse flip-flops the band markers. in ten different presets. Just choose one, do • Clear removes all but one of the band your thing, and the next time you choose that preset, your previous settings will be markers, placed exactly in the center. ready and waiting for you! Multiply | Subdivide | More | Band- Saw Pro does the same thing as BandSaw but with a real-time Numeric window inter- face that lets you still interact with your viewports while open. The cool upshot of this, other than being able to orbit your model to see if the segmenting is working as you’d like, is that it doesn’t require you Figure 7-8 201
Chapter 7 · · · · · · · · · · · · · · · · · · · · · · · · What if you want to remove segments button, and away it goes). The one big dif- from your mesh? LightWave has Construct ference between it and its counterparts is | Reduce | More | BandGlue, which the direction in which you select the polys “stitches” bands of polys together in much to be glued. Just remember that you’re the same way BandSaw cuts them apart. selecting the polys that will become one The tool has no interface (just click its band around your model. Note “Elegance” in Modeling Something that takes most folks a while to pick Animation for complete information on charac- up on is an overriding concept of elegance in ter rigging.) whatever it is you’re doing in 3D. This applies To help us use as few segments as possible to modeling, animating, texturing, lighting — in making our mesh do what we need it to, we all aspects of working in 3D. can adjust the weight by which the sub-patch Your best work will come from using the is controlled by its cage. This information is absolute minimum number of “whatsits” stored on each individual vertex as the Sub- needed to hold your “schiznit” in place — no Patch Weight. Positive values increase the pull more and no less. of the control vertex on the sub-patch surface, Tools like BandSaw can let you really load where 100% makes it touch its control vertex. up your mesh with lots and lots of segments, Negative values relax the sub-patch’s pull and it’s very tempting to do so. But the best toward its control vertex. Map | General | Air- modelers build their meshes with the barest brush is a tool that lets you modify the values minimum number of these isoparms necessary of your currently selected weight map in real to keep the exact shape they’re going for. time. Sometimes a good modeler will spend half the It’s important to note that the vertices in time it took to create the mesh just going your object are not inherently assigned to any through it again and again, looking for places given weight map, including SubPatch Weight. he can optimize it and removing anything that While Weight Shade will show your vertices as isn’t absolutely necessary to hold its shape. having a value of zero, until you actually This optimization not only makes for a assign a map value to them, they have no model that’s quicker to refresh when working value whatsoever. You can directly enter values in both Modeler and Layout, but when working for selected points under the Information win- with characters, it means that it is a lot easier dow for your selected points, or you can use to rig (set up for character animation). It also Map | General | Set Map Value. While this means that the bones that drive its deforma- information may not be of immediate use as tion will create shapes that look a whole lot you’re learning the software, higher-end better than on a mesh that has a lot of seg- functions such as Dynamics do utilize vertex ments. (See LightWave 3D 8 Character map assignments, so keep this bit of informa- tion in the back of your head. Figure 7-9 202
· · · · · · · · · · M o d e l i n g 3 : S u b - Pa t c h O r g a n i c M o d e l i n g Magnet Modify | Translate | Magnet is a great closer to the center of the sphere of influ- tool for working with your sub-patch sur- ence will be affected more than those at its face model as if it were a lump of digital outer edge in accordance with the falloff. clay. It’s a tool I use extensively to rough in This is very similar to what we’ve seen my basic forms when sculpting anything already with the Bend, Taper, and Twist organic (characters, heads, artifacts, tools. whatever). If you establish (and continue to manipu- With the Magnet tool active, you right- late) the Magnet tool’s sphere of influence click and drag in a viewport to set its in a single viewport, the sphere will be “sphere of influence” and then left-click and more like a cylinder, extending infinitely drag to move your mesh around. Points through space. Figure 7-10 Figure 7-11 203
Chapter 7 · · · · · · · · · · · · · · · · · · · · · · · · When you manipulate the Magnet tool’s Perspective viewport in Figure 7-11 shows sphere of influence in multiple viewports, it how I usually like to work with my sub- becomes a true ovoid that can be used like patch models, with Independent Visibility a traditional sculptor’s tool, pressing and active and choosing not to show cages, pulling at a mass of Super Sculpey. (The guides, or the grid.) Pole Modify | Transform | More | Pole takes underrated tool that is very helpful for Size (Pole Evenly tool) and Stretch (Pole organic modeling — especially “futuristic” tool), and blends them with the sphere of design. influence of the Magnet tool. This is an Figure 7-12 Vortex Modify | Rotate | More | Vortex Tool also is an underrated tool that is very help- takes the Rotate tool and blends it with the ful for quickly creating graceful, fluid sphere of influence of the Magnet tool. This curves. Figure 7-13 204
· · · · · · · · · · M o d e l i n g 3 : S u b - Pa t c h O r g a n i c M o d e l i n g Subdivision Order Does the order in which your sub-patch to enter the Texture Editor, and set up surface model is diced up into its tinier the dented texture shown in Figure pieces matter? It matters a whole lot — and 7-16. We get a very cool “insta-moun- one of the best ways to show this is by tain,” strongly reminiscent of the using a variant on the old “single-poly artwork of Roger Dean, the artist for mountain” trick. the Yes album covers. 1. Start with a 5x5 sub-patch grid. 2. Bring the 5x5 sub-patch into Layout, and set its Display SubPatch Level to 42. Then under its Deform tab, click on the T button next to Displacement Map Figure 7-16: A displacement map actually moves the points of the mesh, whereas a bump map just “fakes” it by working with how the light plays across the surface. These are the settings used to Figure 7-14 create the mountain in Figure 7-15. Figure 7-15 205
Chapter 7 · · · · · · · · · · · · · · · · · · · · · · · · (Do you want to see something neat? Load Scenes\Chapter_07\Subdiv_ Activate World Coordinates for your dis- Order.lws, activating each layer in turn, so placement map, remove your falloff values, only one is active at a time, to see other and then move your object about. You’ll see nifty settings. your object flow through the texture! It’s a Subdivision Order tells LightWave when neat way to understand more about the to apply its subdivision surfacing algorithm workings of textures in general. Be sure to to the polygonal cage. If you tell it to apply try this in all three axes.) its smoothing last, the displacement map is The two inactive textures in Figure 7-16 only displacing the 36 points of our 5x5 are other examples of different kinds of cage. If the smoothing is applied before the terrain. displacement map, the displacement map has all 44,557 points to push about. Mac-Specific Info Subdivision Order can really come into play when you’re working with animating a Because of the current weirdness with character. The quickest, most reliable ani- the Mac version of Dented, Mac users mation comes from subdividing your will have to use a Texture Value of 20.2, character using the After Motion or Last instead of the 4.2 shown in Figure 7-16, options. This way, the bones are only hav- and play with the texture’s position in ing to calculate their influence on, say, 7,000 order to get decent mountains. (But it’s points instead of the sometimes astronomi- worth it — no other procedural does cally high number of points in even a mountains like Dented.) Display SubPatch Level setting (“animation (Special thanks to Robin Wood!) resolution”) character’s mesh. Figure 7-17: Modifying the Subdivision Order setting. 206
· · · · · · · · · · M o d e l i n g 3 : S u b - Pa t c h O r g a n i c M o d e l i n g Note If you want to freeze your mountain’s defor- Save Transformed Object also respects the mations in place for use as a prefab object, Display SubPatch Level setting. “Exporting” our File | Save | Save Trans Object will save your mountain as it exists in Figure 7-15 will give us object as it exists on its current frame of LW’s a mesh with 88,200 polys! If you want to save world-space — transformations, displace- your transformed object as an object you can ments, bone movements, and all. (Be sure to still use as a sub-patch model, set Display choose a name different from your original SubPatch Level to 0 before using Save Trans- object; otherwise, you’ll replace the original formed Object. with the object as you’re seeing it right now in Layout’s viewports!) ... Sub-patches open up a whole new level for Just remember the credo of good 3D both modeling and animating. Modeling modelers and animators everywhere: Your complex meshes can now be done in a frac- best work will come from using the absolute tion of the time it would take to noodle all minimum number of “whatsits” needed to those minute polys. Animating with a cast hold your “schiznit” in place. of sub-patch characters means once we choose our Display SubPatch Level and Note Render SubPatch Level settings, we can I can’t stress enough how cool it is to have a enjoy the speed of low-resolution animation crowd of SubPatch Level 0 characters all on meshes and the beauty of high-res render screen at once and still have screen-refresh meshes without having to think about or do rates that are actually conducive to animat- ing. (In 1996, by contrast, three low-res anything more than just press . characters in Softimage slowed an R10K down to a mind-mangling crawl!) 207
Chapter 8 Organic Modeling Exercise 1: “One-Minute” Spaceship This chapter shows how to create one of would like to reproduce it exactly). The those “one-minute wonders” that you’d see important thing is that the box is cen- at trade shows and the like. It’s not sup- tered on the X axis and has two posed to be spectacular; it’s just meant to segments along the Z axis. get you more comfortable with using 2. Activate Symmetry mode, and then sub-patches to actually do something. check that your model is indeed cen- 1. Create a box with dimensions similar to tered by clicking on some polys (or the one in Figure 8-1 (the Numeric points) on one side. If your model is window is shown just in case you centered, the corresponding geometry Figure 8-1 208
· · · · O r g a n i c M o d e l i n g E xe r c i s e 1 : “O n e - M i n u t e ” S p a c e s h i p on the other side will also be selected. Smoothing Angle of 0º. (You will see no (If your box isn’t centered, with Sym- visible change in your model at this metry inactive, use Modify | time.) Translate | Center to center it on all 5. Using the Stretch and Move tools, axes, and then reactivate Symmetry position these polys similarly to what mode.) you see in Figure 8-4. Don’t move 3. Select the rear two polys at the sides. them off the sides of the ship; just (See Figure 8-2.) “squish” them a bit — these are the 4. Apply Smooth Shift with an Offset of bases for what will become the wings. 0 m, a Scale of 100%, and a Max Figure 8-2 Figure 8-3 209
Chapter 8 · · · · · · · · · · · · · · · · · · · · · · · · Figure 8-4 Note 6. Next we’re going to use Bevel on only the top rear poly. Apply only an Inset I bet you’re wondering when we’re going to get to sub-patches. Don’t worry, we’ll acti- (we’re exploring using a different tool vate them for this model in just a bit. I want to do the same job). This poly is the to make a point of how working with base of the tail. (See Figure 8-5.) sub-patches is almost exactly like working with polys, the only differences being that 7. Use Stretch and Move to get this poly with sub-patches, you never have to worry the rest of the way to where it needs to about anything being non-planar, and how- be. (Remember, with Symmetry mode ever you manipulate your mesh, you must active, you need to do your mouse keep your sub-patches as quadrangles (or triangles). work on the positive side of the X axis!) Figure 8-5 Figure 8-6 210
· · · · O r g a n i c M o d e l i n g E xe r c i s e 1 : “O n e - M i n u t e ” S p a c e s h i p 8. Now for the moment we’ve all been 9. With the tail poly selected, use Smooth waiting for — deselect everything and Shift as you did before for the wings press to activate sub-patch and then position the new poly as you surfaces. (It’s not much to look at, but see in Figure 8-8, making the tail fin. it’ll start looking better in a moment.) Once you’ve got your model matching the figure, use Smooth Shift on the poly again, and move it just the barest of microm- eters so its points aren’t directly on top of the points from which it originated. Figure 8-7 Figure 8-8 Note A trick you will eventually pick up on is the • Press (you’ll be in Points selec- “Space, two-tap.” (But why wait?) tion mode). Modeler has two primary selection modes: • Press to activate sub-patches (if you Points and Polys. You use to toggle have no selection defined for your points between them. If you’re working with polys in selection). Polygon selection mode and want to view your • Press again. model as sub-patches without “letting go” of the polys you currently have selected: You’ll be right back where you were, in Poly- gon selection mode, with the same polys selected. Only now, your model is being viewed as sub-patches. 211
Chapter 8 · · · · · · · · · · · · · · · · · · · · · · · · (This has the effect of “flattening” the top Note of the smooth shifted area, making the edge For the rest of the book, whenever we of it nice and sharp. This is one of the ways smooth shift a sub-patch, let it be under- you can make a sub-patch model have stood that it is with an Offset of 0, a Max “crisp” areas of definition. It’s not quite as Smoothing Angle of 0, and a Scale of 100% — just as we’ve done for all the smooth elegant as setting a value of +100% for the shifts so far in this chapter. SubPatch Weight setting for the desired geometry, but it is a popular trick. Moving it just that little bit means that the points 10. Next, use the Smooth Shift and Move won’t get eliminated if you were to do a tools on the two wing polys to get the Merge Points somewhere down the line.) preliminary shape of the wings. Figure 8-9 Figure 8-10 Figure 8-11 212
· · · · O r g a n i c M o d e l i n g E xe r c i s e 1 : “O n e - M i n u t e ” S p a c e s h i p 11. Now, just to add some “nifty-ness” to the polys away from the ship to get an the ship, use Smooth Shift on the tips avian effect (Figure 8-10). of the wings again. Leaving the front of 12. Move and stretch the points of the the new polys very close to where they ship’s nose, as shown in Figure 8-11, were, use Stretch to pull the back of and you’re done! Figure 8-12: Not bad for a spaceship you can build in under a minute! ... What we did here isn’t earth-shattering or work on the “snarf-blat” section, I’ll save ground-breaking, but it does get you started “Whatsit_ w22.lwo” and then save as thinking about how you can use sub- “Whatsit_w23.lwo.” This way if I totally patches to build whatever you desire. You botch the “snarf-blat” section, I can always can see how quickly you can rough in a go back to the way the “whatsit” was before shape that you can work back into, using I started (unintentionally) mangling my BandSaw, Smooth Shift, and Bevel to con- masterpiece! tinue to layer in detail — honing… Don’t be afraid to cut your losses when refining…perfecting. you’re modeling, reverting to an earlier A suggestion from my own experience is state. When you tackle a troublesome sec- to use LightWave 8’s Save Incremental to tion again, you’ll be coming at it from the save multiple revisions of your work as you experience of having been there before. Not go. For example, if I’ve got my “whatsit” to only will you finish that section more quickly a point where I’m pretty happy with the than if you had stuck it out, you’ll finish it “doohickey” section of it, before starting markedly better almost 100% of the time! 213
Chapter 9 Organic Modeling Exercise 2: Character Body Now, using the same basic techniques we bit, you are allowing yourself the ability to explored in the previous chapter, we’re see where you can make things better. going to model a character’s body. In follow- ing along, you’ll see how quickly you can Note get the job done by roughing-in first and As with everything (in this book, out of this then going back and adding detail later. book, as you move through life), this is only I’ve found that it’s easy for artists to get one way of working. This is not the “be-all swept away in the minutiae of the work, not and end-all” of anything. There aren’t hard-and-fast rules as to how a character wanting to move on until what they’ve done should be built. You just do what is most looks “perfect.” There are three issues I forefront in your focus. Let this chapter serve have with this way of working. One, it to give suggestions to you to inspire your makes for a very slow working process. own ways of working. Push, pull, play! Let your creativity be your guide! (Save multiple, Two, human perception is referential; we incrementally numbered revisions of your can’t easily tell what’s “right” and what’s work, so you know you can get back to “wrong” without something with which to where you were, wherever that happens to compare it. Three, when you come back to be!) “The man who makes no mistakes does a piece, even after only half an hour, you not usually make anything.” — Edward J. see things that you missed before. By let- Phelps ting the rough forms have time to air out a Torso 1. Create a box (centered along the X active, lasso all of the points on the axis) that is three segments high, four right side of the object to check its segments wide, and two segments symmetry. If the points on the left side deep. Surface it with the name Shirt, get selected as a result, you know that and let’s get going. your object is truly symmetrical. (It’s 2. Set Val of all the points along the box’s easier to fix something slightly out of center to X=0 to make doubly sure that alignment now than it is to fight with it they are indeed in the center of our vir- later on down the road.) tual world. With Symmetry mode 214
· · · · · · · · O r g a n i c M o d e l i n g E xe r c i s e 2 : C h a r a c t e r B o d y Figure 9-1 3. Next, with sub-patched surfaces acti- 4. Then, using Drag, move some of the vated and Grid Snap set to None, use corner points in toward the center of Magnet to push the box around until it the model to take some of the sharp becomes “torso-ish.” (Here’s where edges off the piece. (See Figure 9-3.) knowledge of anatomy and drawing Just use your best judgment. You don’t comes in handy — you know what the have to get things perfect here; we’ll viewer needs to see to have him asso- go back and really refine things once ciate it with what you have in mind.) we can use the completed character for reference as to what needs to be done. Figure 9-2 “Sooner is better than later!” — Joan, The Messenger 215
Chapter 9 · · · · · · · · · · · · · · · · · · · · · · · · Figure 9-3 Arms and Hands Let’s add the arms and hands to the torso and stretching them to just outside of created in the previous section. where the deltoid would be. 1. Select the four polys shown in Figure 2. Now hide everything else and turn 9-4 (Symmetry will select the four on your selection back into polys so we the other side) and use Smooth Shift can more easily see its defining shape. (as always when working with sub- Drag the points around until the seg- patches, with an Offset of 0 m and a ment is roughly more circular. Max Smoothing Angle of 0º), moving Perfection isn’t necessary. (Try not to move any point too far from where it started. We’re just making our char- acter’s arms come from something “round” rather than something “rhomboid.”) Figure 9-4 Figure 9-5 216
· · · · · · · · O r g a n i c M o d e l i n g E xe r c i s e 2 : C h a r a c t e r B o d y Figure 9-6 3. With the rest of your model visible 4. Use Smooth Shift, Move, and Stretch again and your selection returned to again, positioning the selection just sub-patches, use Smooth Shift, Move, inside where the shirt’s cuff would be. and Stretch so that the segment is now 5. Now, smooth shift and stretch the seg- right where the character’s elbow will ment so it just reduces the size of the be. (You will probably want to put in tube (like where the sleeve meets the more detail segments later, using cuff on a baggy sweatshirt). Then move BandSaw, but for now, for the ease of us it into the sleeve just a bit; this will being able to tweak our character’s help us more easily get at its points base forms and proportions, build him later, and it will also give us a nice with as few segments (isoparms) as “bump” where the cuff and sleeve possible.) meet (shown in Figure 9-8 as polygons to better illustrate what we’re talking about). Figure 9-7 Figure 9-8 217