Essential LightWave 3D- P19

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Essential LightWave 3D- P19: 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 20 · · · · · · · · · · · · · · · · · · · · · · · 12. Render this, and see how it looks. (You Fur can look very, very different with may want to add shadowing, so you can and without it.) If you’re reasonably see what you’re really getting, if you happy with the results so far, it’s time intend to use it in the finished render. to refine it further. Refining the Beard and Mustache Mustache hair tends to grow out from the 2. Return to Layout and open the Object philtrum (the groove in the center of the Properties panel if you’ve closed it. upper lip), often leaving the middle without Right-click on the line that says hair at all. Since you can’t vary the combing SasLite Seen on Beard, and choose on a surface with SasLite, the only way to Copy from the drop-down menu that achieve that is to separate the Mustache appears. Right-click again, and choose surface from the Beard surface, and divide Paste. That will give you two identical it into two pieces. So we’ll do just that. copies of the displacement. 1. In Modeler, select the polys that form 3. Open one of them and change the Sur- the mustache and hide the rest (tap the face Name(s) to lMustache. Leave key). Then select the half on the everything else the same, except for positive X axis, and give it a new sur- the Comb X value. Make it pretty high. face, say lMustache. Tap the
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair Figure 20-33: New values for the left half of the mustache. 4. Click OK to close it, and use the copy/ paste trick again to make a copy of it. Change the parameters of the copy so that it’s applied to the rMustache sur- face, and put a minus sign in front of the Combing value (for instance, –80%). That will send the hairs along the –X axis, or toward the right cheek, and away from the center of the face. Render to see what you have now. 5. If the break along the philtrum is too pronounced, go back into Modeler, select the points on either side of the center line, and bring them closer to the center. You might also want to split the mustache so it can conform better to the shape of the lip. (I used the Edge tools to do that here.) Figure 20-34: The beard and mustache. 529
Chapter 20 · · · · · · · · · · · · · · · · · · · · · · · Figure 20-35: Modify the beard geometry further, if need be. 6. Keep refining and making test renders until you have the beard and mustache you are looking for. Don’t be afraid to add another couple of surfaces, blend the density, put in streaks of a different color, etc. You can have up to eight instances of SasLite in a scene. (If you want more, you can render your scene in a couple of passes, and put them together in post.) 7. For this beard, I added a BeardThin surface on either side of the lower lip (just a couple of very small polys) and a BeardWhite surface to give him a couple of gray streaks. If you want to dissect what I’ve done, you can go through the SasLiteBeard.lwo file on the CD in Objects\Chapter20. Each Figure 20-36: Finished beard. step listed here corresponds to a layer in the model. 530
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair 8. When you’re finished, and it’s just what fibers. If you want grass to grow higher on you want, you can cut the beard polys, the bank of a river, if you want a werewolf’s if you desire, and paste them inside the fur to bristle along his back, if you want to head. (The SasLite displacements will model a soldier with a crewcut — all you be on the “Beard” object, not the need to do is make sub-surface polys, and “Head” object, so you’ll have to pull them back for shorter fibers or push copy/paste them to the head if you do them toward the surface for longer ones. this.) The extra polys make it a bit (Or, really, just get the full version, and do it trickier to animate the head (you’ll the easy way with maps and effectors.) have to include them in your endo- You can do the same thing for eyebrows, morphs), but if you can’t afford the full eyelashes, and the hair on a character’s version of Sasquatch, they will let you head, but there’s another way to accomplish add believable hair, beards, mustaches, these effects that we have yet to explore. fur, etc., to your models. Instead of using subsurface fur patches, we can use long hair guides, which are also You can use the same principles anytime supported, in a limited fashion, in SasLite. you want to vary the length of SasLite Creating Hair with Long Hair Guides Long hair guides are two-point poly chains Making hair guides can be grueling, but (two-point polys that share a point with it doesn’t have to be. The more control you another two-point poly) that direct the flow want or the more complex the hairstyle, the of the fibers. To work in SasLite (or more guides you’ll need. The process I’m Sasquatch, for that matter), it’s necessary about to show you isn’t the easiest, but it for the point on the “root” end to have a dif- will show you a way to make a whole lot of ferent surface than the rest of the chain. guides reasonably quickly, without using (That’s how the plug-in determines which any third-party plug-ins. You won’t normally end is which.) They are usually named need quite this many, but just in case you “Hair” and “Root” to keep things simple. do, here’s a good way to get them. SasLite will generate a lock of hair that 1. Begin by lassoing all the polys that follows the general direction of the guide. could have hair growing from them. The number of hairs in that lock, their Then tap the (right curly bracket) length, and how closely they follow the key to Select Connected and get the guide is determined by the number and next ones, too. (Because of the way placement of polys in the chain and the set- that subpatches work, the curve tings in SasLite. changes when polys are abruptly Let’s start with the hair on his head. removed. By grabbing the polys next to There are several methods to do this, the the ones that you actually want, you “point” of all of them being to spend less can ensure that doesn’t affect the polys time creating the guides than it would take you need.) to actually grow the hair. 531
Chapter 20 · · · · · · · · · · · · · · · · · · · · · · · Figure 20-37: Select the scalp polys and the ones next to them. 2. Paste those polys into a new layer. For subpatches. Tap the key to this particular method, we’re going to subpatch those polys, and freeze again. use a lot of points to grow hair guides (If you don’t think you need as many from, so tap + (or go to guides, then you might want to freeze Construct | Convert: Freeze) and only once, or change the Subpatch level freeze the polys, which will make faces (in either direction) before freezing.) from the “virtual” polys in the Figure 20-38: The poly-rich mesh that results from double-freezing. 532
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair 3. We don’t need the polys, just the inside the scalp , tap (or points. So tap (or go to Con- Modify | Transform: Jitter), and jit- struct | Reduce: Remove | Remove ter the points a tiny bit so it looks more Polygons) to “kill” the polys. That will like hair roots and less like transplants. leave you with a bunch of points that Name this layer Roots. (You can name aren’t connected to anything. Copy the layers in the Layers window found whole bunch and paste them into under the Windows menu.) You can another layer. Now begin to lasso and delete the points from the previous remove sections to form the actual layer now, if you feel so inclined, or hairline. As always, it helps if you have save them “just in case.” a reference. If you accidentally get too 5. We’re going to rail extrude the many, you can grab them from the pre- two-point polys, but right now, we’ve vious layer, and paste them in here. only got points. Rail Extrude doesn’t Just tap to merge the points, so work on points. Therefore, we must you won’t have to worry about multiple convert our points into polygons. Go to overlapping point problems. Keep the Create tab and click on Polygons: going until you are happy with it. Points to Polys. Give them the sur- 4. When you’re satisfied, tap to face Root (), copy the whole merge points. (Even if you haven’t cop- thing, paste it into another layer, and ied points from another layer it’s good call it Hair Building. Tap again, to do this just to be safe.) Then reduce and change the surface to Hair. the size of the wig slightly so it fits Figure 20-39: Trim the extra points away from the hairline. (Original points shown in background for clarity.) 533
Chapter 20 · · · · · · · · · · · · · · · · · · · · · · · Figure 20-40: The Roots layer, all ready to grow hair! 6. Select the one-point polys around the minutes, but it’s easier if the bulk of hairline, including a good portion of the the hair is done first. (Depending on front, and place them into an empty the style of the hair, these points could layer called Hairline. We’re going to be along a part, just in the front, on the style them more carefully in a few side, or wherever the scalp shows.) Figure 20-41: Put the Hairline in another layer for more careful treatment. 534
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair Figure 20-42: Begin to make curves to describe the bulk of the hair. 7. Open an empty layer, and put the Head 10. Make two to five curves, and then and Hair Building layers in the back- begin to copy/paste them, and move ground. Beginning at the center, or them around the head, rotating so that where the part is, start to make a they will follow the line you want the series of spline curves (you can use hair to have. The more curves you use, whichever of the Curve tools you are the smoother the hair will be, but be most comfortable with). aware that there are limits to how 8. We are going to use Rail Extrude to many splines Rail Extrude can handle extrude the one-point polys, which will before it simply tells you there are too automatically make two-point poly many. (If you reach those limits, you chains from them. The spline curves can divide your hair into smaller sec- we just created are the rails the polys tions to extrude, of course.) will be extruded along. 11. When you have enough to describe the basic shape of the hair, somewhere In SasLite, the actual hairs may appear to between 5 and 20 or so, depending on be a little shorter than the hair guides, so the hairstyle, put the curves in the keep that in mind while you are making background, and the Hair Building them. layer in the foreground. Tap + 9. Work from the hairline at the collar to (or Multiply | Extend: Rail the front, so you can make each curve Extrude) to open the Rail Extrude: slightly overlap the one below it. This Multiple panel. will keep the hair falling naturally, instead of having fibers diving under the ones below. 535
Chapter 20 · · · · · · · · · · · · · · · · · · · · · · · Figure 20-43: The head, with enough rails to describe the main hair mass. 12. Choose to make Segments according to quickly.) Leave the Strength at 2, and Length, make them Uniform, and disable both Oriented and Scaling. choose around 5 or 6 segments. (There 13. Click OK, and you’ll have a bunch of are limits to how many vertices two-point poly hair guides! Name the SasLite allows, and they add up Figure 20-44: The Rail Extrude: Multiple panel. 536
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair Figure 20-45: The bulk of the hair guides, made in a snap! layer Wig. We’ll be collecting the hair use the Size tool to make it all here as we build it. larger. Now, of course, there are things that can go 16. Now, if you want to shape it as you go, a little weird at this step. which is easier from my point of view (but also requires more steps), cut the 14. The most common problems are the hair. (That sounds like barber talk, but I guides swirling in odd directions, piling up in ridges, and/or leaving bald spots really mean to cut using the + when viewed against the head. Most of shortcut, of course.) these are caused by the same thing — 17. Open the Roots layer and paste the not enough curves for the number of hair in. Tap to merge points, and one-point polys being extruded. (I’ve accept the defaults. That will merge found that sometimes, for some reason, each chain with its root. Select the Hair you can also fix the swirling problem by material (using the Statistics window undoing and deleting the last point on ) and tap the key (or go to the curve. So if you’re pretty sure View | Select: Select Connected) to there are enough, you might want to get the roots, as well. Cut again, and try that.) paste back into the Wig layer. Now you can tweak the hair to your heart’s To fix them, of course, either add some desire, without any fear of the guides curves, or extrude a fewer number of becoming disassociated from their one-point polys at once. roots. Go ahead and do that, shaping it 15. If a lot of the hair is below the surface, until you are happy with it. The Magnet then your splines might be too close to tool works well for this, but of course the head. Undo, select all the points on you can use any tool you are comfort- the spline except the endpoints, and able with. 537
Chapter 20 · · · · · · · · · · · · · · · · · · · · · · · Figure 20-46: Ridges leaving bald spots, corrected by adding four curves. Figure 20-47: If the splines are too close to the head, the guides will be inside it, not outside. 538
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair from the Hairline layer in one of the Side viewports (Right or Left) so you get both sides, cut it, and paste it into an empty layer. Then make two or three splines, as if you were modeling the outermost hairs (and perhaps a middle hair) from that group. Mirror those splines across the X axis, and tweak the mirrored ones a tiny bit so it’s not too symmetrical. (I use the Drag tool ( + ) for that, because I’m a Figure 20-48: Styling the hair with the Magnet control freak, but you might want to use tool. Jitter.) 18. Once you are happy with that part of 19. Then Rail Extrude the points, using the hair, it’s time to work on the front more segments if you can afford it. If and the hairline. This is done the same they haven’t gone wonky (that’s a tech- way, except that you work on only a nical term), put the guides and the head small section at a time, which gives you in a foreground layer, and take a look. If much better control and allows you to they don’t penetrate anything they style the hair with (relative) ease. shouldn’t (like the ears), and if they are standing out from the scalp, move on to By small, I mean small. The trick is to keep the next step. You don’t have to be the sections to 20 or 30 of the one-point exact, since you can style the section polys at a time. with the Modify tools. But the closer If the portion of the hairstyle you’re you are, the easier that will be. Just working on is symmetrical, select a group don’t make yourself crazy with it. Figure 20-49: Symmetrical groups of one-point polys and rails. 539
Chapter 20 · · · · · · · · · · · · · · · · · · · · · · · Figure 20-50: Extruded guides, viewed against the head. 20. If the style isn’t symmetrical, it will Note take a little longer, because you’ll have If you want to have the best, thickest hair to grab the one-point polys one group you can have, then make sure you have at a time. You might find, though, that more points at the tip than you do at the root, and extrude by knot, not length. it’s still easier to copy the curves and SasLite uses the placement of points on the tweak them from group to group than it guide when it determines how to “grow” the is to build a whole new set of curves. hair. The more the points are concentrated at the tip, the thicker and longer the hair will Once again, I find it’s easiest to work from grow. back to front, with the finished hair piece and the roots you are currently working with in the background. 21. As you finish each section, if you are using the style-as-you-go method, cut it and paste it into the Roots layer, merge the points, select the Hair sur- face, Select Connected, and paste it back into the Hair Building layer. Then, with that layer in the foreground and the Wig in the background, tweak the hair until you are satisfied with the shape. (Don’t forget to add Minoxidil to make the hair healthy and strong.*) Once it looks good, cut it again, and paste it into the Wig layer. As I men- Figure 20-51: Making the rails for another section of tioned before, this method has more hair. steps, and may take more time, but for me, it gives much better results (with a lot less stress). (* Don’t go looking for the Minoxidil but- ton. It’s a joke! If you didn’t get it, take a break, right now.) 540
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair Figure 20-52: Tweaking a section, working into the wig. While you are styling, remember that you finish it, and paste it into the Wig these are hair guides, not hairs. Every one layer. of them will turn into multiple hairs when 23. Once a section is pasted into the Wig, it’s rendered with SasLite. Complete cover- open the Hairline layer, cut the next age isn’t necessary, or even particularly section of roots, paste it into the Hair desirable. It’s better to make hairs that are a Building layer, and make curves for it. little offset, with an even amount of room (You might want to save all the curves, between them. or you might want to delete them. It’s 22. If you aren’t using the style-as-you-go up to you.) method, then just cut each section as 541
Chapter 20 · · · · · · · · · · · · · · · · · · · · · · · Figure 20-53: As each section is finished, select the next group of one-point polys. Note When you’re in the Wig layer, keep an eye on the number of points you have. Remem- ber that SasLite will only allow 25,001 points per object that has SasLite applied. If you exceed that number, you’re going to have to break the wig into different layers. Since SasLite also allows only eight instances of the plug-in per scene, you’ll need to keep the total below that number unless you want to render in multiple passes. Think about how many instances of SasLite you’re using for eyelashes, eyebrows, hair, beard, mustache, etc., when deciding if you can afford to run over on the guides. Figure 20-54: Keep an eye on this number in the Wig layer, so you don’t exceed SasLite’s limit of 25,001. 542
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair All of this will probably take a while, espe- for now, you can find the SasLiteHair- cially if you haven’t done this kind of thing End.lwo model in the Objects\Chapter20 before. But eventually you’ll have a full directory on the CD. (On the other hand, if head of hair guides, ready to convert into you really want to dissect the procedure, realistic hair. there’s a model called SasLiteHair- 24. If you haven’t used the style-as-you-go Guides.lwo there, too, which has layers for method, select all the one-point polys each step of the process.) in the Root layer, paste them into the When you decide that your wig is as Wig layer, and merge the points now. If good as you can get it without a test render, you decide that you want to style it, go then it’s time to do exactly that! If your wig ahead. is too large for SasLite to handle (25,001 polys, remember), you’ll have to split it. If you want to practice making the guides some other time and just want to use them Splitting Hairs to Work with SasLite’s Limits Lasso the section you want to remove, and into another layer. Both of them will need to then tap the key to select all the con- have their own instance of SasLite. Good nected polys. (Anything without a root isn’t thing that you can copy/paste the options, going to work, remember, so you need to huh? keep the whole length of each individual How you split it, of course, is up to you. guide together.) Cut them and paste them Since it’s a wig for a balding man, I’m Figure 20-55: If you need to split the wig, try to do it so you get extra versatility out of it. 543
Chapter 20 · · · · · · · · · · · · · · · · · · · · · · · splitting it so that I have the possibility of some fashion that allows extra versatility, if an additional hairline, as shown in Figure you can. 20-55. It’s always a good idea to split it in When it’s as ready as can be, save the head, and load it into Layout. Rendering the Hair 1. As always, you will need to apply the 3. Set your parameters however you want SasLite displacement in the Object them. Figure 20-56 shows what I’m Properties panel, as well as the Pixel using for this particular model, if you Filter in the Processing tab of the want to copy them. Once again, I’m not Effects window. going into detail about them, since I’ve 2. Open the options for the Displacement done that already in the LightWave 8 plug-in, and choose Make long hair docs. using guide chains from the list on 4. Once that’s done, you need to make a the left. Once again, you’ll need to type test render to see if your hard work is the name of the surface into the Sur- resulting in the hair you envisioned. face Name(s) field. Unless you make a But, if you render now, you’ll see the typing error, you should see the green polychain hair guides, as well as the numbers change, so the correct num- hair. That’s probably not what you ber of surfaces is displayed on the left. want. (In this case, 1 of 2. The second surface is the Root.) Figure 20-56: The SasLite panel when using long hair guides. 544
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair So, with the Object Properties window still sides that will be visible in your final open, click on the Render tab, and set the render, until you have what you want. Object Dissolve to 100%. That won’t have (Don’t be afraid to copy and paste sec- any effect on SasLite, but it will cause tions of guides to duplicate them if LightWave to ignore the guides when it there’s a thin spot in the hair. Just be renders. (Don’t forget to disable the shad- aware of the SasLite limits when you owing as well to save render time.) do.) The whole process can take an hour or more, but the results are well worth it. (Besides, if you get a nice wig, you can often reuse it for other characters with a minimum of restyling.) Figure 20-57: Set the Object Dissolve to 100% to hide the long hair guides. 5. Tap , and see what you’ve got. If you need to go back and tweak the guides, do that and make another ren- Figure 20-58: The finished wig-and-beard der. Keep going, checking from all the combo. Long Hair Guides, the Sequel! We’re going to use another method of deal- 1. Select a couple of polys from the eyelid ing with long hair guides to give this guy where you want the eyelashes to grow. some eyelashes. This one is a lot faster, at Then go to View | Selection: More | least for me, but it does use a couple of Select Loop to get the “rim” of the third-party plug-ins. The good news is that whole lid. Tap the (right curly you can download them from the web for bracket) key to expand the selection to free. the loops above and below that, so that there won’t be distortion when they 545
Chapter 20 · · · · · · · · · · · · · · · · · · · · · · · Figure 20-59: Select the polys for the lashes and the ones next to them. are isolated (just like we did for the whole loop (), but don’t resize or head). Copy and paste into a new layer. move it in any way. Just click in a 2. Freeze the polys ( + ). viewport and drop the tool. Deselect Select two of the ones on the new the polys, then tap to merge the edge, just as you did before, and Select points. That will leave you with a cou- Loop again. Then smooth shift the ple rows of two-point polys. Figure 20-60: Select the edge loop, smooth shift, deselect, and merge points. 546
· · · · · · · · · · · · · · · · Simulations 3: Fur and Hair 3. Usually, you just delete those polys; 5. Select the “extra” one (whichever one but we’re going to use a free plug-in you choose), and delete it. Then run from D-Storm called Polygon2Curve the Polygon2Curve plug-in. (When to make them into a spline, which we’ll you used Add Plug-ins (Utilities | then use to rail clone a lash. (You can Plug-ins), it probably went into the download the plug-in from the D-Storm Utilities | Plug-ins: Additional menu. plug-in site at http://www.dstorm.co.jp/ So check there for it.) That will make english\plugin\modeler.htm.) each poly into its own tiny little curve. 4. Select the 2 Vertices polys from the Merge them into one long curve by Polygon Statistics panel (click the + in tapping (Detail | Polygons: the line), tap (double quote) to Merge Polys). invert the selection, and delete the 6. With the curve still selected, tap the polys. We don’t need them any more. to toggle to Points (It will look like you’ve selected every- mode, select the two points in the cor- thing, but you really haven’t. Check the ners of the eyes, and tap + Statistics panel after deleting and you’ll (Multiply | Subdivide: Split) see the two-point poly chains are left.) twice to split the curve into two pieces. Figure 20-61: Select the two-point polys from the Statistics panel. 547