Essential LightWave 3D- P4

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Essential LightWave 3D- P4

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Essential LightWave 3D- P4: 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 3 · · · · · · · · · · · · · · · · · · · · · · · · Figure 3-64 Figure 3-65: Looking more like a logo. We’re just about there! 4. Center your text again (see step 1). Note 5. Select Multiply | Extend | Extrude Depending on which direction the surface to activate the Extrude tool. normals of your polys to be extruded are facing, dragging one way will create the 6. With the Extrude tool active, click and new geometry with their normals facing drag in a line along the +Z axis on “out” (which is what you want most often) either a Right or Top viewport (basi- or “in” (which means you’re seeing “through” the outer surface of the object, cally, anything that isn’t Perspective or seeing only the “insides,” which can be cool where you’re looking at the letters for faking the effect of volumetric lighting). head-on will do). The more you drag, the more the text will be extruded. 7. Press to accept the effects Save this text you’ve created, as we use it of the Extrude tool (see Figure 3-66). in an upcoming example on using one layer of your object to modify another. 78
  2. · · · · · · · · · · · · · Modeling 1: Foundation Material Figure 3-66 Extender Plus ex•tend v. 1. To spread or stretch forth. example, I’ve increased the number of 6a. To cause to be of greater area or vol- sides and segments to provide a very ume. (Merriam-Webster Online Dictionary) smooth surface. Now hit to cen- ter the ball. What Extrude is to polygons, Extender is to 2. Using your right mouse button, drag points. Specifically, it expands the geometry out a lasso selection around the top half around the selected points. of the sphere including the band of Let’s use Extender Plus to make a sim- polys just below the center. ple bowl. 3. Press the key to remove 1. Activate the Ball tool and drag out a these polygons. This leaves us with a circle in the Top view. The exact size nice simple bowl shape. As you can doesn’t really matter. Now, holding the see, however, the bowl has no interior. key (or the middle mouse but- We’ll use the Extender Plus tool to ton), drag in the Back view to create a remedy this. perfectly round sphere. For this 79
  3. Chapter 3 · · · · · · · · · · · · · · · · · · · · · · · · Figure 3-67: Deleting the top half of the ball leaves us with a generic bowl shape. 4. Select a couple of points along the open edge of the bowl, then activate the Select Loop tool. With all of the points along the edge selected, go to the Mul- tiply | Extend menu and select Extender Plus. Figure 3-68 Looking at your geometry, it will 5. Select the Modify | Transform | Size appear as if nothing has happened. On tool and scale the selection in slightly. the contrary, Extender Plus has actu- You’ll see the lip of the bowl “magi- ally expanded the edge of the ball. The cally” appear. only problem is that this new edge lies directly on top of the old one. There- fore, in order to see the effect of the Note Extender Plus tool, we must modify If your selection does not scale inward the new geometry by moving, rotating, evenly, make sure the Modes button at the or sizing it. bottom of the interface is set to Action Cen- ter: Selection. 80
  4. · · · · · · · · · · · · · Modeling 1: Foundation Material Figure 3-69 Figure 3-70: The final bowl with a smooth surface. 6. With the edge points still selected, this process again, moving the points click on the Extender Plus tool again. and sizing them so that they’re not Then activate the Move tool. Holding poking through the outside polys of the the key down (or using the bowl. Continue this process several middle mouse button), drag down more times until you’ve reached the slightly to form the initial inside edge bottom of the bowl. of the bowl. 8. Finally, click on Extender Plus once 7. Click on the Extender Plus tool again, more. Click on the Weld Average tool followed by the Move tool. Move the from the Detail | Points menu. This new edge down slightly. Then use the will weld all of the points together at Size tool to shrink the selection so that their averaged center. the points are inside the bowl. Repeat 81
  5. Chapter 3 · · · · · · · · · · · · · · · · · · · · · · · · Booleans and Solid Drilling Bool·e·an adj. Of or pertaining to an be subtracting the volume of the object algebraic combinatorial system treating in the background layer, we choose variables, such as propositions and com- Subtract and click OK (see Figure puter logic elements, through the operators 3-74). AND, OR, NOT, IF THEN, and EXCEPT. , [After George Boole (1815-1864).] (The American Heritage Dictionary) With Booleans and solid drilling, you can use parts of your object to “carve out” spaces in other parts of your object. This is powerful computing, and you’ve got to make sure your prep work for these kinds of operations leaves LightWave with as clean a start as possible. (Non-planar polys are a surefire way to generate errors.) But when you’re thinking ahead and planning your modeling tasks as if you were playing a strategy game or solving a puzzle, these tools can be incredible allies. Figure 3-71 Hot Key Block Booleans and Solid Drilling Boolean Solid Drill Merge Points In a nutshell, with both Booleans and solid drilling, you’re using an object in a back- ground layer to modify an object in a foreground layer. The following exercises show how to use these tools. Let’s start with the objects shown in Figure 3-71 — a white cube on Layer 3 and an orange sphere on Layer 4. Figure 3-72 1. To use the sphere to “carve out” a sec- tion of the cube, we put the sphere into the background layer and leave the cube in the foreground. 2. Construct | Combine | Boolean brings up the Boolean window Figure 3-73 (Figure 3-73). Since we are going to 82
  6. · · · · · · · · · · · · · Modeling 1: Foundation Material Instead, you use layers to “cut holes in” or “stencil” shapes into other object layers. For the next exercise, I’ve created a sim- ple white plane (a two-dimensional box) and use the text we created in the Extrude exercise to “stencil” the shape of the text onto the plane (see Figure 3-76). Note You should notice that the plane to be sten- ciled in Figure 3-76 has five width segments and three height segments. This is because the text I wish to stencil has 2,876 points on its face polygons. Trying to stencil this would be asking LightWave to try to have many Figure 3-74 more than its maximum number of points per poly in the resultant white plane that Showing only the foreground layer after the bound the letter shapes. Boolean operation, we see the “bite” taken I’ve helped LightWave by breaking this plane up into segments, so the maximum out of the cube by the volume of the sphere. point-per-poly limit won’t be pushed by any Notice how the sphere’s orange surface is now one poly. (After the Solid Drill operation, the color for the “bitten” polys! using the information window for all polys, I With Solid Drill, you don’t “carve out” was told that the largest number of points any poly had was 428.) bits of an object like you do with Booleans. Note When you do a Boolean operation, the • Automatic “fuses” multiple points into points of the “bitten” polys aren’t “stitched” one point only if the points are laying directly to the points of the original object exactly in the same space, with not even a — this gives a nice, sharp edge when both micrometer difference between their exact surfaces have Smoothing active. This can position. This is what you use to fuse the cause a problem if you do a lot of selecting pieces after a Boolean operation. with the Select Connected tool because the • Fixed lets you decree “all points that are two pieces aren’t really connected; they’re within ‘X’ mm of each other shall now only laying exactly on top of each other, become one,” and so forth. which isn’t the same thing. After you’ve merged points, especially if you’ve just merged with the Fixed option, it’s a good idea to peruse the Point and Polygon Statistics windows. Merging points gets rid of points, not the poly information tacked to those points. You need to check to see if you Figure 3-75 have any “0 Point” or “2 Point” polygons (or points that don’t belong to any polygons at all) that you don’t specifically want. To connect the “bitten” part of a Boolean After merging points, you may have to operation with its original object, you must adjust the smoothing angle of your surfaces use Detail | Points | Merge Points. so they still give you a nice, sharp edge where they meet. 83
  7. Chapter 3 · · · · · · · · · · · · · · · · · · · · · · · · Figure 3-76 Like with Booleans, the object in the back- ground layer is the “cutter,” and the object Note in the foreground layer is the object to be If you don’t see the effect of the Solid Drill cut. The “cutter” must pass through the function, make sure that you are viewing the object in one of the wireframe display types “cuttee.” (such as Textured Wireframe). If your drilled surface is the same as the object it’s drilled into, it won’t be visible in Smooth Shaded or Textured view types. Note Figure 3-77 • Core leaves just the polys of the fore- ground layer in the shape of where the two 1. I want to use the text to stencil a new objects intersect. surface into the white plane, so I • Tunnel “cuts a hole” in the polys of the choose Solid Drill, which brings up foreground layer with the shape of the object the Solid Drill window and activates in the background. • Stencil cuts the polys of the foreground the Surface box where I can type in a layer and assigns a new surface to them. new surface name or select an existing • Slice cuts just the polys of the foreground one from the pop-up menu. layer, leaving them with their original surfacing. 84
  8. · · · · · · · · · · · · · Modeling 1: Foundation Material Figure 3-78 2. The Construct | Combine | Solid and/or X axes, Bend would have made all Drill operation leaves me with the text our letters non-planar, which Triple may or that was in the background layer “sten- may not have been able to make sense out ciled” onto the plane. (Unlike a Boolean of (because a poly in the shape of a letter is operation, all these polys are connected so very complex). — there is no need to merge points.) However, if we want our flying logo to look even cooler than it already does, we Before we move on to beveling and can use one of the Boolean operations to smooth-shifting, there is one more cool add some curve to our text. (Light scatters thing I want to show you how to do with so much better off a subtle curve than it Booleans. does off a flat plane. This is part of knowing With the Bend tool, we got our text to how to make something look professional.) bend around the Z axis. But if we had also wanted our text to bend around the Y 85
  9. Chapter 3 · · · · · · · · · · · · · · · · · · · · · · · · 1. To do this we need a bit more depth in 2. Next, as in Figure 3-80, bring up an our letters as we work (see Figure empty foreground layer, and put your 3-79). So, dragging using the right text into the background as a reference mouse button ( + as you create a highly tesselated mouse-button on a Mac with a sphere, the surface of which will repre- one-button mouse) will let you lasso sent the curve of our text’s new face. the polys you want selected. Grab the rear polys of your text and move them back a bit to give us some room. Figure 3-79 Figure 3-80 86
  10. · · · · · · · · · · · · · Modeling 1: Foundation Material Figure 3-81 3. With our text in the foreground layer when they were all flat, even, and ever so and the sphere in the background, acti- slightly boring. There are exactly no non- vate Boolean again, but this time planar polygons. (After doing the Boolean, choose Intersect. The end result will the points of the back of the logo were create an object that consists of only moved forward to a place where they the area where the two volumes are looked good.) “inside” one another. Save what you’ve got here. We’re going The letter faces now catch the light in a to do some cool things with it in future much more interesting way than they did chapters. Figure 3-82: The finished Boolean operation. 87
  11. Chapter 3 · · · · · · · · · · · · · · · · · · · · · · · · Note If you wanted to have all the letters the same thickness and not get thicker toward the center of the logo, as is the case in Figure 3-82, you could jump back to where things were at Figure 3-81. Instead of doing a Boolean, do a Solid Drill | Core, then Extrude the results, and resurface the sides of the letters to their original surface. You’d then have something like Figure 3-83. Figure 3-83 Bevel and Smooth Shift Bevel and Smooth Shift are two of the most Hot Key Block frequently used modeling tools. They do Bevel and Smooth Shift almost the same thing, except Bevel affects Bevel every polygon individually, while Smooth Smooth Shift Shift treats all contiguous selections as a single unit. With four of this sphere’s polys selected, Multiply | Extend | Bevel “pushes” each poly out separately. Dragging up “pushes” the polys out from their original position, and dragging left makes the polys smaller. Figure 3-84 88
  12. · · · · · · · · · · · · · Modeling 1: Foundation Material Figure 3-85 With four of the sphere’s polys selected, to “suck them into” their originating vol- Multiply | Extend | Smooth Shift ume; drag right to “push” them out, away pushes and/or pulls the polys, but Smooth from their original volume. Shift treats them as a single unit. Drag left Edge Bevel and Super Shift The last two modeling tools we’ll look at adjacent polygons. When we talk about are Edge Bevel and Super Shift. As you edges in this case, we’re referring to more might have guessed, these are variations of than just the geometry along the perimeter the Bevel and Smooth Shift tools men- of your object. Edges occur at the bound- tioned above. aries of every single polygon. Edge Bevel is useful anytime you need to create geometry between two or more Figure 3-86 89
  13. Chapter 3 · · · · · · · · · · · · · · · · · · · · · · · · By edge beveling the top of this box, we makes the bevel larger, while dragging to create the same basic effect as if we had the left makes it smaller. Edge Bevel is used the traditional Bevel tool. However, if particularly helpful when working on char- we select the edge around the center of the acters, where beveled edges can be used to box, we can “open” it to create an additional create wrinkles in the character’s skin. band of polygons. Dragging to the right Figure 3-87 Super Shift is a handy alternative to the tra- modeling.) For now, let’s take a quick look ditional Smooth Shift tool. While Smooth at the differences between Smooth Shift Shift allows you to push and scale groups of and Super Shift. polygons, it does not give you independent When pushing these polys out of the ball control over either process. Super Shift, using Smooth Shift, Modeler looks at each however, does, thus enabling you to per- individual polygon’s normal to determine form a “group bevel” on your polygons. In how it should move and scale the entire addition, Super Shift automatically gener- group. Super Shift, on the other hand, aver- ates polygons with zero offset and a ages the group’s normals. What that means Maximum Smoothing Angle of zero simply in practice is that Super Shift won’t “puff by activating the tool. (While the benefits of up” the polys on a curved surface as it that may not make sense now, they will pushes them out. later when we talk about sub-patch Figure 3-88 90
  14. · · · · · · · · · · · · · Modeling 1: Foundation Material Super Shift also scales your polys using a When used on an irregular selection, the local inset, which is similar to how the differences between Smooth Shift and Bevel tool operates. Moving your mouse to Super Shift become apparent. As you can the left scales the group in. Moving your see, the “T” that was pushed into the ball mouse to the right scales it out. Moving using Super Shift maintained its shape your mouse up pushes the polygons out. much better than the “T” using Smooth Moving your mouse down pulls the poly- Shift. gons in. Figure 3-89 ··· That concludes our discussion of a respect- chapters are still only just scratching the able number of modeling tools. A modeler surface. could almost go his entire career and never You will reach your fullest potential by use more than these, but in later chapters pushing, peeking, and playing. If you view on modeling, we add to this repertoire of 3D as a puzzle, game, or toy through which yours so you’ll be able to handle just about all things are possible with the “right” pat- anything a client cares to put into your tern of patience, exploration, observation, capable hands. Remember, even all the and retention, there will be no limits as to tools explored in the more advanced what you can do. 91
  15. Chapter 3 · · · · · · · · · · · · · · · · · · · · · · · · Note To this end, I’d like to take a moment to point (or as little) help and as many (or as few) you toward one of the programs available on hints as you need. the companion CD. Sherlock is a game that I hesitate to call Sherlock a game, even trains your mind to see even the most seem- though it is a fun and rewarding way to pass ingly complex tasks as simply a process of the time. Part of this is that often in computer elimination. games, from the moment you click “Go,” the “ . . .When you have eliminated the impossi- computer will do everything in its power to ble, whatever remains, however improbable, keep you from reaching your goal, whatever must be the truth . . . ” — Sherlock Holmes it happens to be — and I, for one, find this to be a waste of my time. Sherlock, on the other hand, gives you all the resources you need to solve the puzzle — and unlike solitaire, your winning is not dependent upon chance. Your suc- cess, or lack thereof, rides entirely upon your shoulders (think about it). Success in Sherlock, as in Light- Wave, feels like an achievement, not a fight. The other reason I hesitate to call Sherlock a game is that it is much more than just an enjoyable way to pass the time. It is training for your mind. (“Use it or lose it.”) Exploring this kind of training, you begin to become accustomed to seeing the Figure 3-90: Sherlock whole picture as patterns of interre- lated subsets and steps. When temporarily stumped in either LightWave or Sherlock (PC only) by Everett Kaser Sherlock (or life), you become able to take a ( is a “game” where, step back and see the next step toward the like LightWave, you are given all the clues solution, sometimes just sitting there in plain you need to do what you need to do. In this sight, patiently waiting for you to take notice case, it is to find the locations for each icon of it. within a grid from 3x3 to 8x8, with as much 92
  16. Chapter 4 Layout 1: Foundation Material One of the best ways to think about the life.” 3D is just a tool to give you rent-free, whole process of 3D is to equate it to build- unlimited soundstage space. Once you get ing scale models and then photographing beyond the fact that you can’t really “hold” them. All the different parts of the process what you’re working on, becoming good in are the same. You’ve got to sculpt the 3D is mostly a matter of finding out how pieces that you’ll eventually turn the cam- what you know about your physical, practi- era on, sometimes “kit-bashing” free cal “reality” translates into the tools you models found on the Internet or cannibaliz- use to manipulate this virtual “reality.” ing old pieces laying around in an attic-like part of your hard drive. If you were working with practical Note (“real”) models, you’d paint the models so Some of the most impressive work to come they looked just the way you wanted, from out of Babylon 5 was from a guy in his late 40s who, until he was hired, had never whatever camera angle you were going to worked in 3D CGI before. He was a photog- shoot them. You’d find a private stage to set rapher, and as such, he understood how light them up. You’d get lights to shine on them behaved. After he got the knack of Light- and bounce off of diffusing boards and Wave’s controls, his 3D work began to reflect how he would light and shoot an screens. You’d look through your camera or event in “real life.” director’s viewfinder and see what needs to Being a computer whiz has very little to do be touched up on the models, placement, or with being good at 3D. After you know your lighting. You’d possibly add some smoke or way around the tools, it’s all about what you choose to focus your camera on and how wind and, making sure exposure, filters, you choose to showcase that environment. and camera speed are all correct, you’d let Anyone, given the time, can learn the tools the cameras roll! — possibly one of the most liberating things The best-looking work I’ve seen from about working in 3D. There are no limits! 3D artists is from people who were thinking as though they were “doing this in real 93
  17. Chapter 4 · · · · · · · · · · · · · · · · · · · · · · · · LightWave’s Camera If you were to go out and look at a 35mm • The Resolution pop-up menu lets you motion picture camera or even a profes- choose from a list of presets that define the sional-level 35mm single-lens reflex, you’d “base” size of your rendering. see a whole lot of settings that you can play with. LightWave does a lot to pattern its • Resolution Multiplier is a pop-up menu that lets you scale your image (a mul- camera’s adjustments after its “real-world” tiplier of 50% on a resolution of 640x480 counterpart, so if you come to LightWave would yield a rendered image of 320x240) knowing how to use a film camera, the tran- while still letting any special post-process- sition will be very smooth. Even if the most ing filters that calculate on a per-pixel basis think in terms of the “base” size set under Resolution. (See the following note if this is confusing.) • Width and Height change to reflect the combi- nation of the resolution and its multiplier. You can enter values here directly if you need to render to unique-sized formats. Figure 4-1: The Camera Properties window. • Pixel Aspect Ratio is an input field that changes you’ve done to study photography is take a automatically when you select a (base) res- night course at a local college, you’ll notice olution from its pop-up menu. Pixel Aspect things like shutter speed and F-stop that at Ratio takes into account the fact that the the very least should sound familiar. pixels (picture elements) for PAL and LightWave’s Camera Properties window, NTSC aren’t perfect squares, as they are on accessible by clicking Properties while the a computer monitor. Both PAL and NTSC, camera is selected, gives you access to and their regular and wide-screen modes, many of the settings that control how your each have separate aspect ratios. Because output will look. this field is automatically updated when you • The Current Camera pop-up menu change the resolution to one of these televi- lists all the cameras you have in your sion formats, you’ll probably never have to scene; each camera can have its own, sepa- worry about this value. But here it is, just rate settings. in case. 94
  18. · · · · · · · · · · · · · · · Layout 1: Foundation Material Note Borders option, thereby giving you an One of my favorite post-process filters is image whose dimensions are exactly the Glow Effect, which we get into in Chapter size of your limited region. 17. The way its settings work tell it how many pixels out from a “glowing” surface to Note spread the glow’s effect. With Resolution Multiplier, I can do a test Limited Region is useful when you’ve got an render with a multiplier of 25% to save time. intense scene that takes minutes to render If the “base” resolution of my render was and you are working on tweaking one small 640x480, it would then be reduced to area of that scene. You could also use 160x120, meaning that LightWave would Limited Region if you wanted to render a only have to figure out the colors of 19,200 “wide-screen” format and a “TV” (1:1.333) pixels, not 307,200 pixels. Because Resolu- version without destroying your composition tion Multiplier is used (instead of manually by “panning and scanning.” (You’d be doing setting the image size), the pixel-based set- the same thing that some directors do when ting in Glow Effect is also scaled. they choose to shoot on super 35mm when Once I get the look I want in my test they know their work will be seen on both render, I can return the multiplier to 100%, the silver and small screens.) knowing the effect I saw in the tiny, quick test will be the same in the full-size render. • Segment Memory Limit opens a panel where you can specify the amount of • Limited Region is a pop-up menu that memory that LightWave sets aside for the allows you to specify a smaller portion of rendering of each piece of the finished the frame to render. It can only be adjusted frame. The default of 8 MB is large enough while looking through the Camera view. to render a 640x480 frame in a single Limited Region Borders will render full- segment. sized frames; however, everything outside Small Segment Memory Limit settings the limited region area will be masked off in are helpful when you have a limited amount black. Limited Region No Border will crop of physical memory on your computer or on the area normally masked out by the a render node. It is almost always faster to render an image in a single segment than it is to have a frame split up into several seg- ments. What you want to do is find a setting for your computer that is as large as you need it to be to render your average work in a single segment without causing your machine to “dig too deeply” into virtual memory resources. (Disk access will always be slower than RAM.) Note Some plug-ins require you to render your Figure 4-2: Pressing while looking through a scenes in a single segment. So, if you’re get- Camera viewport both activates Limited Region ting weird results in your renders when and allows you to adjust it by clicking on the dotted things looked just fine in your tiny test ren- yellow line that appears and dragging it to resize. der, try upping the Segment Memory Limit. 95
  19. Chapter 4 · · · · · · · · · · · · · · · · · · · · · · · · • Frame Aspect Ratio is a readout that information about the current settings tells you about the ratio of your frame’s based on Zoom Factor and Aperture Height. width to its height. In Figure 4-1, Frame Aspect Ratio reads “1.333” because, with a • The Antialiasing pop-up menu gives you a list of settings from Off to Enhanced Pixel Aspect Ratio of 1.0 (1 to 1) when you Extreme that specify how many passes divide width by height, you get 1.333. (The LightWave makes to take the “jaggies” out industry officially calls this “1 to 1.333,” or of a picture. (See Figure 4-3.) “1:1.333.”) • Segments tells you how many seg- ments LightWave will need to render an image the size you’ve asked for with the amount of memory allocated under Seg- ment Memory Limit. • The Zoom Factor menu allows you to choose how you want to change Light- Wave’s camera’s zoom. Zoom Factor, Lens Focal Length, Horizontal FOV (Field of View), and Vertical FOV change the input field to the right to reflect that particular way of thinking about camera zoom. Figure 4-3: Here’s the text we created in the last chapter. The top version was rendered without antialiasing. You can see the sharp edges, especially where the light text meets the dark Note background. The bottom version was rendered Notice the little “E” button to the right of the with Enhanced Low antialiasing. Notice how much input field. You can access LightWave’s smoother those areas are. Graph Editor through this button to enve- lope this setting to change over time. Note The difference between Low, Medium, High, • Aperture Height changes the size of and Extreme antialiasing settings in Light- the “gate” inside LightWave’s virtual cam- Wave is the number of passes used to era. It is a measure, in inches, of just how “explore” the detail areas of a piece. Low tall the exposed frame of film would be makes five passes, Medium makes nine passes, High makes seventeen passes, and were it a real-world camera. You use this Extreme makes thirty-three passes. With when you are matching your rendered each pass, LightWave is able to figure out imagery to be composited onto film that has more and more details that are smaller than a pixel. been shot with a real camera. It affects how LightWave’s camera calculates Depth of Field and Lens Focal Length. Aperture Height defaults to the height of a frame of • Adaptive Sampling is normally used when smoothing an image. This means that 35mm motion picture film. Many other pre- after it renders a pass, it goes around and sets are available through the pop-up menu finds all the pixels that differ a certain to the field’s right. amount from their neighbor. (This level of • Focal Length and FOV (Field of acceptable difference is set in the Thresh- View) are readouts that give you old input box.) LightWave then re-renders 96
  20. · · · · · · · · · · · · · · · Layout 1: Foundation Material only those pixels, letting everything else the precise effect of your object’s motion stay as it is. that would be too quick for LightWave’s Using Adaptive Sampling, you can get a “shutter” to “freeze.” very good-looking image in a fraction of the Because of the way this motion blur is time it would take to render and antialias on calculated, factoring in a minutely different most other rendering engines. Without point on LightWave’s timeline for each Adaptive Sampling, LightWave re-renders antialiasing pass, the more passes, the everything in the entire frame for each smoother and more “realistic” the render pass. This is good for when you have tiny will be. So, the higher the level of anti- surfacing details or intricate texturing with aliasing, the better your rendered image; detail smaller than a single pixel of the ren- this is why you’d want to use High or dered image. Rendering without Adaptive Extreme levels of antialiasing when render- Sampling helps keep these “sub-pixel” tex- ing Motion Blur (or Depth of Field). tures from “crawling” during an animation. • The Particle Blur check box tells LightWave whether or not you want to blur Note single-point polys (particles) as well as Adaptive Sampling tends not to do so well “regular” objects. when rendering text that is just a set of flat polygons. When rendering text, it is best to • Blur Length is linked to the Shutter deactivate Adaptive Sampling and switch to Angle and Exposure Time readouts, an Enhanced level of antialiasing, which fig- which tell you about your Blur Length set- ures in almost twice as many samples per ting in terms a cinematographer is familiar pixel. with. The higher the number, the longer the blur. (You can get some neat effects by hav- • Soft Filter renders the objects in your ing a Blur Length well over 100% or well scene with the “softness” of film (the back- under –100%.) ground isn’t affected by Soft Filter). This setting doesn’t seem to be a “blur” of a kind Note that post-processing can mimic; it appears The Motion Blur settings in the Camera to actually change the way LightWave ren- Properties window give you the most accu- ders. If you’re looking for a more “filmic” rate kind of motion blur, but they aren’t the render, as opposed to something more only way to have your objects blur in rela- tion to their change in position over time. A “video-like,” this, in conjunction with a Film huge factor in creating any art is to “give the Grain image filter, is your key to getting illusion of” rather than “exactly recreating.” that look. Clever artists/programmers found out that they could “smudge” the pixels of an object • Motion Blur becomes an option when based on its motion data available for that you activate Antialiasing. With Motion Blur particular frame. And so came about a neat on, each antialiasing pass is not only ren- little plug-in called Vector Blur. You can find it under Scene | Effects | Image Processing | dered in its entirety, but each pass is also Add Image Filter. You can find out more rendered from a slightly different point on about this plug-in in the LightWave manual, LightWave’s timeline. (Adaptive Sampling but in short, it is a way of quickly giving the is not active when rendering with Motion illusion of motion blur without LightWave having to go through all the steps necessary Blur or Depth of Field, even though the to create good-looking exact motion blur. Adaptive Sampling box may remain checked.) The result of this is an image that shows 97
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