Essential LightWave 3D- P6

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Essential LightWave 3D- P6

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Essential LightWave 3D- P6: 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 5 · · · · · · · · · · · · · · · · · · · · · · · · Lathe The Lathe tool lets you take something 2. Select Multiply | Extend | Lathe to you’ve created and “spin” it around to cre- activate the Lathe tool. Click in the ate an object. It creates geometry from Back viewport, as shown in Figure either polygons or curves. (Lathe is some- 5-12, and drag straight down. (The axis times called Sweep in other 3D packages.) you are creating defines the angle 1. Create a two-dimensional disc some- around which your disc will be where to the left of X=0. “lathed.”) Figure 5-11 Note Note In addition to using the Numeric window to Sometimes Lathe creates the new polys with change the Lathe settings, you can drag the their normals facing the “wrong” way. Be root handle around to move the center of sure to check this every time after lathing the effect. You can drag the rotation handles and flip the polygons if necessary. (Even if to specify where you want the “lathing” to you’re using a double-sided surface on your start and stop. polys, it’s always a good idea to have your Press the to reduce the normals facing the “right” way.) number of segments; press the to increase the number of segments. 138
  2. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s Figure 5-12: Multiply | Extend | Lathe activates the Lathe tool. Figure 5-13: Lathe also works with splines (curves — also known sometimes as “rails”) to quickly create rather neat-looking chalices and other “turned” objects. (The Sketch tool (Create | Curves | Sketch) was used to quickly draw the curve that was then lathed with the same settings as the disc in Figure 5-11.) Figure 5-14: The Offset field lets you “skew” the lathe operation, letting you create springs and other nifty doodads! (Remember that you can enter a mathematical formula into any of LightWave’s Numeric input fields. So, if, as in this illustration, you didn’t quite know what five complete revolutions would be in degrees, just enter 360 * 5, and let LightWave come up with 1800.0º for you.) 139
  3. Chapter 5 · · · · · · · · · · · · · · · · · · · · · · · · Taper Under the Modify | Transform menu, LightWave offers two kinds of tools that Note taper your geometry. Taper lets you control Taper, Twist, and Bend all work best when the amount of effect on each axis of the you have many segments along the effect’s axis of the geometry you are deforming. taper, depending on how much you move your mouse up and down or left and right. Taper Constrain, on the other hand, affects as it extends along the Y axis. Drag left or your geometry in both directions of your right, up or down to taper your object. taper at once (for instance, if you wanted a (Technically, the Taper tool successively Doric column to evenly taper as it rises). scales the selected geometry relative to the With a Taper tool active, click in a Top distance of the selected geometry’s viewport to taper your selected geometry bottom.) Figure 5-15: The Taper Constrain tool in action. 140
  4. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s Pressing opens the Numeric win- • The Shape buttons let you invert the dow for Taper and activates a little gizmo effect (so the bottom tapers instead of the (seen on the “Base Object” in Figure 5-15) top), have the taper affect both ends at to give you a visual interpretation of the once, or affect just the middle of the Taper tool’s effect. Right-clicking and drag- selected geometry. ging the gizmo’s ends will let you exactly position and angle the tool’s effect. • The Presets pop-up menu gives you quick access to four combinations for the Through the Numeric window, you can sliders below it that shape the curve of the adjust the falloff of the effect to “sculpt” linear falloff. (You can see examples of the how Taper affects your selected geometry. effect of changing these sliders in Figure • The Falloff pop-up menu lets you 5-15.) choose from several complex ways of let- ting the taper effect dissipate through • The Range of the effect defaults to Automatic. However, by right-clicking and space. (We use Linear because it is what manipulating the gizmo, you are telling you will most often use. However, through LightWave that you want to specify a fixed this pop-up menu, the tool can even refer- angle and/or position for the effect. Clicking ence the settings on a weight map that on Automatic releases your specified, fixed you’ve created. To find out more about settings. these falloff settings, explore the Light- Wave manual.) Twist The Twist tool is something I don’t use all You can move and angle the area of effect that often, but when I need it, there’s noth- for the twist by right-clicking and dragging ing else that can fit the bill like this tool can. on the gizmo in the viewports. This sets Technically, it spreads out rotation through the Range to Fixed, just like in Taper. Click your selected geometry in relation to how on Automatic to revert to LW’s automatic far each bit is away from the effect’s root. In settings. layman’s terms, it twists stuff. The Twist tool is accessed through Modify | Rotate Note | Twist. Twist is a cool tool, but it is notorious for cre- Twist also obeys the same kind of falloff ating many non-planar polys. Check your rules that Taper does. By shifting the falloff work for non-planars after using Twist. sliders, the twist in Figure 5-16 (on the following page) begins gently from the bot- tom, increasing as it reaches the top of our stack of segments. 141
  5. Chapter 5 · · · · · · · · · · · · · · · · · · · · · · · · Figure 5-16: The twist axis is established by clicking in a viewport, “spindling” the effect directly away from you in the viewport in which you clicked. (Think of the axis around which you’d twist a tall stack of napkins, playing cards, or saltine crackers. You establish this axis by looking straight down at the stack.) Bend We used Bend when making our flying text logo in Chapter 3. It follows along the same rationale as Taper and Twist. Figure 5-17: Click and drag in a viewport to bend your selection as if it were a car’s radio antenna and you were looking straight down the antenna at the effect’s axis. Note Unlike Twist, Bend is usu- ally very good about not creating non-planars, if you bend a poly only once. After hitting a selection more than once with Bend, check to see if it’s created any non- planar polys. 142
  6. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s Smooth Scale/Move Plus Smooth Scale pushes your selection out What if we wanted to make ThinGuy along each individual polygon’s normal by (one of the characters in LightWave 3D 8 the distance you enter in its input window. Character Animation) into “PlumpGuy”? (It will pull your selection in if you enter a (Hey, anything can happen in production, negative value.) Unfortunately, Smooth right?) Scale has no real-time interface, which I select the polys I want to push out and makes its use less than intuitive. That’s then select Modify | Translate | More | why the Move Plus tool is such a welcome Move Plus. By right-clicking and dragging addition to LightWave 8. Move Plus fea- up, I can push the polygons out along their tures all of the functionality of the normals, essentially puffing it up. Dragging traditional Move tool when using the left down pulls them back in. I often use the mouse button. However, when used with Move Plus tool on a character’s fingers to the right mouse button, it performs a make them fatter or thinner. real-time smooth scale. Note Due to the way Smooth Scale and Move Plus operate, they can break the symmetry on your object. Be sure to check symmetry after working with one of these tools. Figure 5-18: ThinGuy. Figure 5-19 143
  7. Chapter 5 · · · · · · · · · · · · · · · · · · · · · · · · Figure 5-20: Using Smooth Scale or Move Plus on an entire object can produce some interesting results. (Remember Dig Dug?) Rail Extrude — Single Rail Rail Extrude is a little like those “Leather- smooth it out: Objects\Chapter05\ man” tools that are a combination screw- RailExtrude_Raw.lwo.) driver, pliers, scissors, awl, penknife, and so on. Rail Extrude is one little tool, but it Note does a whole lot of things. Let’s start with Notice the funky little diamond thing at one one of its simple uses and move on from end of the curve in Figure 5-21. That is the there. end I started sketching first. This is the start Have you ever wanted to create one of point of the curve, as far as LightWave’s Rail Extrude is concerned. The circle we create in those “tunnel fly-throughs”? Follow these just a moment should be right at this place if steps: we want the extrusion to follow this curve as 1. Grab the Sketch tool, and draw a rail we intend. You can switch the end LightWave thinks (curve) you’d like to have your tunnel of as its start point by flipping the curve the follow. (You can load mine, if you like. same way you would flip a polygon (). It’s had some points cut from it to help Figure 5-21 144
  8. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s 2. With the curve in a background layer, Note create a disc and move it to the curve’s Carl Meritt’s AlignToRail plug-in, available start point. In order to have it orient on the companion CD, will automatically properly along the curve, you will also line up your polygon to the start of the back- ground curve, making quick work out of an need to rotate it so that its normal is otherwise time-consuming process. like an extension of the curve’s line. (“Spinning” around the Perspective viewport and touching up the rotation where the normal is most out of align- ment is the quickest way to get it aligned well.) Figure 5-22 Note If you want the extruded geometry to have its normals facing out, then you want to have the soon-to-be-extruded poly’s normal facing away from the curve. If you want the new geometry to have its normals facing in, then the poly’s normal should be facing toward the curve. 145
  9. Chapter 5 · · · · · · · · · · · · · · · · · · · · · · · · 3. Once you’ve got the polygon aligned, 4. Accept the default settings shown in Multiply | Extend | Rail Extrude Figure 5-22. The disc is extruded along opens the Rail Extrude: Single window. the curve (looking a little like the It has the following options: ductwork from Brazil). • Automatic segmentation will let 5. Save your object. (Mine is Objects\ LightWave make its best judgment as Chapter05\RailExtrude_1.lwo.) far as how many “slices” to make and 6. With the layer that has the curve in it where they should be so the extrusion in the foreground, select File | Export most closely follows the curve. | Path to Motion. Save the motion • Uniform Lengths lets LightWave somewhere where you’ll have intuitive distribute its specified number of seg- access to it (Motions\Chapter5\ ments so they are all equidistant along TunnelFly-Through.mot is what I the curve’s length. used). You will need to add “.mot” (with- • Uniform Knots tells LightWave out the quotes) to the end of the file for Layout to see it; Modeler doesn’t do this to distribute its specified number of segments with relation to the place- automatically when you use Path to ment and number of knots (points) on Motion. the curve. 7. Now, use Send Object to Layout so • Oriented tells LightWave to rotate we can make a movie of our quick example here. the poly, aligning it to the curve as it is extruded. 8. While in Layout, use and to adjust the grid size so your extruded object fills the screen nicely. Figure 5-23 146
  10. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s 9. Select the camera and use File | Load 13. Under the Controllers and Limits tab of | Load Motion File. Choose the the Motion Options window, set both motion file you created in Step 6 of this Heading Controller and Pitch Control- exercise. ler to Align to Path. You can then go 10. Change the end frame of the Frame back to the IK and Modifiers tab and Slider to 160, and “scrub” the Frame adjust how much your camera “antici- Slider along the timeline. You will see pates” its motion by setting the Align your camera move along the tube to Path Look-ahead field. (It’s easiest (even though it won’t be “looking to use the slider button to the field’s where it’s going” yet). right and “scrub” through your scene, making little adjustments so the cam- 11. Under Display Options, give yourself a era gives you what you want.) Viewport Layout of 2 Left, 1 Right. Set the Top Left viewport to Camera If your polygon normals are facing in, your View and the Right viewport to Top Camera viewport should be showing you View and have it Center Current what it’s like to be looking down that tun- Item. (You can set the Bottom Left nel. (If they aren’t, just switch back to viewport to whatever you’d like.) Modeler, flip them, and return to Layout; if 12. With the camera still selected, press you’re working with the Hub active, when to bring up the Motion Options you get back to Layout, the polys will be window for the camera. (See Figure flipped!) 5-24.) Figure 5-24 147
  11. Chapter 5 · · · · · · · · · · · · · · · · · · · · · · · · Note Align to Path is a controller available only for heading and pitch. You will want to go through your movie and, with General Options | Auto Key Create | Modified Channels selected, rotate your camera on bank where it seems fitting. (You can always reload the motion file onto the camera if you don’t like what you’ve done — so explore and experiment!) 14. Open the Surface Editor, and onto your Figure 5-25: Just a quick F9 of the tunnel we just tunnel’s surface, load in a preset with made. some bump to it so you can see some “nurnage” (that’s the industry’s techni- Spend some time lighting and surfacing cal term for “neat-bumpy-detail”) as your tunnel scene. Render a movie and see you’re flying down the shaft. (I wasn’t how things look. happy with any of the presets that If things move too quickly or too slowly, came with LightWave, so if you want to you may have to change the end frame of use one of mine, load in Surfaces\ your movie and enter the Scene Editor to GrungyCement.srf.) scale your keys. Figure 5-26: You can scale the keyframes for objects in your scene using the Dope Sheet in LightWave 8’s Scene Editor. Click on the first keyframe for your camera (denoted by a green bar), then, holding the key, click on the last keyframe. You can drag the yellow bars on either side of your selection to scale interactively or right-click and choose Numeric Time Scale from the pop-up requester to scale your selection by a specific percentage. If you’re unhappy with the results, simply right-click again and select Undo. 148
  12. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s Note If you would like to pull apart my scene for this exercise, you can find it in the companion files: Scenes\Chapter_05\Tunnel_Fly- Through_F.lws. In the scene, you’ll find a working example of vector blur. You’ll also see an example of a trick using morphing to get a texture to cor- rectly follow a twisting object. There is no right way or wrong way to do anything — so long as the way you do some- thing works. But you should always press yourself to find a new angle on what you’re currently doing, even if it is an idea as well-used as a tunnel fly-through. Figure 5-27: A frame from my take on the (The movie in Figure 5-27 came from Ren- fly-through. ders\Chapter05\Tunnel_Fly-Through.mov.) Rail Extrude — Multiple Rails Now how about “lofting”? Can LightWave from things that can be used as sub-patches do lofting? Absolutely. (very low density) to extremely high-den- sity meshes (for use in slowing even a Cray Note supercomputer down to PC Jr. speeds). Say you wanted to create a strangely Lofting is a term from CAD/CAM programs that work almost exclusively in splines and ergonomic hilt for some alien blade. (See NURBs (non-uniform, rational B-splines). In Figure 5-28.) short, lofting is using splines to guide the creation of a NURB surface. 1. You would first create two curves that “outlined” the shape of the desired form. (The start points should be LightWave will let you guide the extrusion where you intend to put the geometry along multiple background curves. You can that will be extruded.) use this to create any level of mesh density, Figure 5-28 149
  13. Chapter 5 · · · · · · · · · · · · · · · · · · · · · · · · Figure 5-29 2. Next, with the curves in a background layer, create a shape you wish to be Note extruded. In this case, it is a standard Using the Knots setting to determine seg- disc that is wider in X than it is in Z. ment placement means you must be a lot more careful when creating the curves you Position it at the curves’ start points will be “lofting” along. LightWave will try to with its normal facing out. distribute segments and orient them knot for 3. Activate Rail Extrude to bring up the knot. If your object’s silhouette must meet an exact shape, have all your curves made Rail Extrude: Multiple window. It has with the same number of knots, and know the following options: that from the first knot to the last on all • The Segments section allows you curves, LightWave will use them to deter- mine exact placement and angle of the to control how “dense” the extruded extruded segments. mesh is (just like Rail Extrude with only one curve in the background). • Strength is a factor of how “tightly” the extrusion will follow the curves. • Oriented, as when rail extruding with only one curve, “angles” the extrusion as it follows the curves. • Scaling lets your extrusion “expand” on all three axes in relation to the distance between the two curves. Figure 5-30: Using just the default settings for Rail Extrude: Multiple (shown in Figure 5-29), we get our funky handgrip. 150
  14. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s Figure 5-31: You can use more than two curves to Figure 5-32: Again, using just the default settings, shape your extrusion to get even more “organic” we get something that looks even more like it was shapes. “grown” than “machined.” Note Rail Extrude: Multiple can create a lot of non-planar polys. Check your work after using this tool. Rail Bevel Rail Bevel? Yep. It’s a cool tool that lets you 1. Make a simple rectangle. specify the shape of the bevel. (It’s easier 2. With your rectangle in a background to show what it does than to try to explain it layer, use Sketch to quickly doodle a in words.) shape that could be a molding joining the ceiling and walls of a house. Figure 5-33 151
  15. Chapter 5 · · · · · · · · · · · · · · · · · · · · · · · · Figure 5-34 Note 3. With the curve in the background layer, The points of the background layer are used use Multiply | Extend | More | Rail to guide Rail Bevel, not the curve itself. So, Bevel to turn the simple polygon into while you may be tempted to add points to an instant cornice piece. Dragging up smooth things out, don’t. Rail Bevel is guided by the point order, the order in which and down in a viewport will make the the points were created. If you need more bevel wider or narrower; dragging right detail in an area, put your curve in the back- and left will make it taller or shorter. ground and create new points in a “dot-to- (This seems backward to me, so I just dot” fashion along the entire curve, adding in the new ones you need as you go. use the Numeric window for my real-time rail bevels.) Figure 5-35 152
  16. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s Note If you need some serious smoothing on your Freezing a curve turns it into a polygon with a rail bevel, you can select your curve and freeze level of detail relative to the Curve Divisions it (Construct | Convert | Freeze). setting under General Options. Figure 5-36: Only the points created by the Freeze operation matter to Rail Bevel, so even if your curve ends up looking inside out after freezing, the bevel will still look fine. Edge Tools Does LightWave have any tools for working Note with edges? You bet! And once you start using them, you’ll wonder how you ever got In the real world, edges occur at the physical boundaries of an object, such as the edge of along without them. If you’ve ever modeled your desk. But in 3D, edges occur at the with another 3D package, the next few boundaries of every single polygon. When tools will make you feel right at home. we talk about edge tools, we are talking about tools that add, reduce, and delete these boundaries. To this effect, the edge tools are like advanced, interactive versions of the BandSaw and BandGlue tools. Add Edges The Add Edges tool (Detail | Edges | • Position, Distance from Start, and Add Edges) lets you draw new edges onto Distance from End are all methods of your object. How cool is that?! The blue dots determining the placement of the currently that appear when you run this tool are con- selected control point. You can adjust these trol points. Adding a new edge is as simple interactively by clicking on one of the con- as playing “connect the dots.” The control trol points and dragging it along its existing points can be dragged along their existing edge. edges to adjust the new edge’s shape (Fig- ure 5-37). • Grid Snap enables you to constrain the motion of the control points. Without Grid Snap, they will freely move along their existing edge. 153
  17. Chapter 5 · · · · · · · · · · · · · · · · · · · · · · · · Figure 5-37: Adding edges to create a non-uniform “cut” around an object. • Grid Unit allows you to select a method of constraint for the motion of your control points. You can snap to a ratio or a distance. • Ratio looks at the edge on which the control point lies and lets you constrain its movement based on a percent of the source edge’s length. Setting Ratio to 50% will constrain your control point to the very center (50% of the current edge’s length) or either end. • Distance allows you to determine an Figure 5-38: The Add Edges Numeric window. exact size for the grid snap. You can enter any size you’d like; however, if the size is larger than the length of the edge on which • Release Current clears the most recently created edge. the control point lies, the control point will jump to either end of that edge. • Hide Markers turns off the control points. This can make it easier to see the • Stopper allows you to restrict the new edges you’ve created. motion of the control point to a limited area. The settings used to define that area are • Realtime Update shows the creation of your edges in real time. If your graphics similar to those used to define the Grid card is a little older or begins to bog down, Snap. you can turn this off to get better feedback. • Unit allows you to choose a method for defining the Stopper area. • Ratio sets the restriction area to a per- Note centage of the length of the source edge on The settings in the Numeric window are which the control point lies. At 50%, this there to give you a greater degree of control over the edge tools, but don’t let the myriad will lock the motion of the control point of options intimidate you. You can use all of entirely. the edge tools quite effectively without ever • Distance allows you to set a distance opening the Numeric window. Just know these options are available should you need from the beginning and end of the source them. edge to restrict the control point’s motion. 154
  18. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s Reduce Edges Note The Reduce Edges tool (Detail | Edges | Reducing and removing edges can easily Reduce Edges) will remove the selected lead to non-planar polygons. Be sure to keep a watchful eye on your Statistics panel edge and collapse the edges that support it. when using these tools. (The supporting edges are those that run perpendicular to the edge you’re reducing.) This tool works wonders for cleaning up problematic areas of your mesh. Note To reduce an edge, select the control If you right-click, the Reduce Edges tool will point on the edge that you’d like to remove. remain active, allowing you to quickly You’ll see a preview of the effect. To accept reduce multiple edges in your object. this, right-click or press the key. Figure 5-39: Cleaning up our geometry by reducing edges. Remove Edges The Remove Edges tool (Detail | Edges | Note Remove Edges) does exactly what its The Remove Edges tool will remove edges, name implies — it removes edges from but in certain cases it won’t remove the your object. points associated with those edges. Switch to Wireframe view to ensure that no stray To remove an edge, simply click on its points are left in your object. associated control point. As with the Reduce Edges tool, right-clicking allows you to accept the elimination and continue removing edges from your object. Figure 5-40: Removing edges. 155
  19. Chapter 5 · · · · · · · · · · · · · · · · · · · · · · · · Rounder Have you ever wanted a magic wand that right increases and decreases the number you could wave over your objects to make of bevel segments. them look more realistic? Well, you’re in luck! That magic wand exists. It’s called Note Rounder, and it can be found under the Mul- Rounder only works on edges shared by tiply | Extend menu. You see, in the real exactly two polygons. It will not work on sin- world, the corners and edges of every sin- gle, isolated polygons. When working with gle object (no matter how sharp they might Boolean objects, make sure that you have merged points first or Rounder will give you appear) are slightly rounded. This rounding an error! produces a glint along the object’s edge when the light catches it. Unfortunately, 3D software makes it easy to create corners In addition to adding the subtle bevels that and edges that are infinitely sharp. While make objects look more realistic, Rounder technically accurate, they don’t catch the can be used to solve otherwise complicated light like real objects do and when ren- modeling tasks. dered, they look fake. Rounder takes care of The pegbox for this lute is a pretty com- this by adding multi-step bevels to the cor- plex shape, but you can make it very easily, ners and edges of your objects. in just a few steps, with Rounder. Figure 5-41: Rounder turns an average object into a great one. Rounder has two modes. You can toggle Figure 5-42: Robin Wood’s lute object. between them at any time during the tool’s use. In the first mode, Rounder bevels 1. First, make the basic shape, bevel the points (called a chamfer in some 3D applica- top poly in, then down, and use the tions). In the other mode, it rounds edges. Knife tool to determine where the Using either mode is easy. Simply select sides will become straight, between the the points or polys you wish to round, then second and third pegs. Then select the click in any viewport and drag your mouse. four points that belong to the rounded Dragging up and down increases and edges (Figure 5-43). decreases the bevel size. Dragging left and 156
  20. · · · · · · · · · · · · · · · M o d e l i n g 2 : A d d i t i o n a l To o l s 2. Run Rounder. Robin used the settings tools to line everything up) and you’re shown in Figure 5-44. Rounder will done. Just like that (Figure 5-46). instantly round the edges and simulta- neously form the half-circles where the Note round and straight edges meet (Figure The view through the Right viewport (the 5-45). one in the middle) has been rotated 270°. 3. All you have to do after that is use the This makes it easier to fit the image in the picture. But it also means that “down” is to Stretch tool to give the curve the the right of the image, and “right” is toward desired shape (with, perhaps, a bit of the top. tweaking with the Rotate and Drag Figure 5-43 Figure 5-44 Figure 5-45 157
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