LightWave 3D [8] 1001 Tips & Tricks phần 4 pot

UVs 405 William “Proton” Vaughan | UVs | All Levels UV Textured Hair Sometimes it makes sense to texture as you model. Here is one example. When creating hair on your model you can UV texture one chunk of hair while it’s straight, then shape it to your liking and duplicate it all over the head. Then you don’t have to go back and texture every part; it will already be done. Versions: All 406 Robin Wood | UVs | Beginner to Intermediate Make UVs During Primitive Creation When possible, choose Make UVs as you create primitives. (You’ll have to have a UV map associated with your model to enable this command. If you don’t, click the T button in the VMap bar at the bottom and choose (New) from the menu to create one. Uncheck Initial Value when you do.) You’ll know when it’s possible, because there will be a Make UVs check box in the Requester or Numeric panel when you create the geometry. This makes a flat map, which is a lot easier to color. If you don’t need the UVs, you don’t have to use them. But having them might be handy later on. Versions: 6.5-8 407 Rob Powers, Robin Wood | UVs | Intermediate Make the UVs First to Save Time When you create a UV map for your object in Modeler it will apply that UV map based on the current state of the object. Any further modifications to that object (except for adding points or polygons) will not alter that UV map. This work flow is what gave rise to using endomorphs to create a specific UV map on your object. You create the endomorph to edit or flatten out your object and then create the UV map when that endomorph is applied. The method has been men - tioned on many web sites and tutorials before, but another slightly different way that I take advantage of this technique is by creating a UV map on an organic object prior to performing a jitter or twist effect in Modeler. This will keep the UV map clean even when the actual geometry has been distorted. Versions: 6-8 408 Robin Wood | UVs | All Levels Undistorted UV Maps When you are making a UV map, the easiest way to make sure that the pro - jection UVs aren’t distorted on the map is to create a cube that’s large enough to enclose the whole model. (Hold down Control/Ctrl to constrain the tool so you get a cube.) Flip the polys (tap the “f” key) so you can see your model through the cube in shaded views. Modeling | 167 UVs When you select polys to make UVs, make sure the appropriate cube face is selected too, and you’ll have a perfect, undistorted UV map. If you leave the cube there while you select other parts to map, they will all be proportional to each other, too. Then, when you’re ready to arrange the final map, delete the cube. (Paste it into a working file, to be extra safe, in case you decide to remap something.) After that, you can arrange the parts to your liking, scaling them and otherwise manipulating them as desired. Versions: 6.5-8 409 Jonny Gorden | UVs | Beginner UV Mapping If you want to UV map a small section of a surface using an alpha texture to hide the edges, make sure you include all the polygons of the surface in the UV map; otherwise, you’ll get artifacts at the edges of the map. Place the polygons you don’t want the texture to appear on in a transparent part of the UV space. Versions: 6-8 410 Leigh van der Byl | UVs | Beginner Planning and Creating UV Maps Efficiently If I had a dime for every occasion that someone has asked me how to do their unwrapping, I would have … well, a lot of dimes. The fact is that planning and executing your UV maps is simple brainwork. And you have a brain. So you have no excuse for not being able to figure it out. It is mostly with organic shapes (especially characters) that people struggle to figure out their different projections. The first tip I can give is this: Whatever you do, don’t try to unwrap the entire model in a single projection. It’s simply not going to work and you’ll only end up bashing your head into the wall. And don’t feel tempted to use the Atlas option — you will destroy your sanity. When creating UV maps, you need to look at the shape of the object you are trying to unwrap, and divide it into logical sections that roughly form conven - tional, unwrappable shapes. Let’s take a look at an example and examine what shapes can be found in it. If we break up a character like the one at the top of the following page into logical sections, then the task becomes more manageable. Let’s look at each body part. The head is a simple shape. It is roughly spherical or cylindrical in shape, extending down toward the chest. This means that ideally one should unwrap the head in that fashion, as it is a logical shape for it. Of course you could also go and unwrap the head in a planar fashion, but that would create more seams to deal with and you might end up with more editing to do if you go that route. Of course unwrapping the head cylindrically or spherically is ideally done on the 168 | Chapter 4 UVs y-axis, so that the seam runs down the length of the model instead of horizon- tally across the face or something equally annoying. Since the head essentially extends up the y-axis from the body, unwrapping it along that axis makes the most sense. Let’s move on to the torso. A human torso is roughly box shaped or cylindri - cally shaped. Either way is fine. If you unwrap it cylindrically, you will have to do it on the y-axis since, as with a head, the torso extends along the y-axis. Modeling | 169 UVs If you unwrap the torso in a planar fashion, you’ll ideally have to do it in two separate operations — once from the front, selecting only the front-facing polygons, and once from the back, selecting the back-facing ones. Doing it once through the entire section would result in a mess of overlapping polygons that could take a while to edit. If you constructed your character facing along the z-axis, then ideally you would unwrap the planar projections along this axis. 170 | Chapter 4 UVs Moving downward toward the legs now. Legs are simple. They are cylindri - cal. Their length runs along the y-axis, so you unwrap them along that axis. It’s almost too easy. Generally, the easiest way to do the feet is to unwrap them in a planar fash- ion. Once from above and once from below. The same applies to the hands of the model. As for the arms, we have the same situation as the legs, although generally arms would be unwrapped cylindrically on the x-axis if they have been modeled in the usual hands-outstretched pose. As you can see, once you start to analyze your model, you’ll always find that there are logical ways of dividing the model into sections that can be unwrapped. All you need to do is use your brain! Versions: 6.5-8 411 Emanuele Salvucci | UVs | Intermediate Append UV Mapping To create a new projection for some of the currently mapped polygons within the same UV map: 1. Select the polygons you want to remap. 2. Unweld points for the current selection. 3. If you’re going to make an Atlas projection, merge back points for the cur - rent selection. 4. Select Map tab>Make UVs, and choose a projection method and the current VMap. 5. Unweld points for the current selection. 6. Fit the new mapping, moving, rotating, and scaling if necessary. Modeling | 171 UVs 7. Merge points for the current selection if needed. Versions: 6-8 412 Emanuele Salvucci | UVs | Intermediate Stitching UVs You can easily assemble together new UVs on a UV map by using a few interactive tools: the Snap Drag tool, the Unweld and Merge Points commands, and the Flip UV Point Map command. Once you’ve created a new mapping for a group of polygons, proceed as fol - lows to stitch together the new UVs and create a continuous mapping: 1. Unweld the currently selected polygons and move them near the polygons you want to stitch them with. 2. Check if points are continuous by selecting a border point on the UV Texture view and Shift-selecting the highlighted point in the Perspective view. 172 | Chapter 4 UVs 3. If they’re opposite, then select all points of a group and apply the Flip Tex- ture Map UVs command, choosing the “V” option in this case. 4. Keeping the current point selection, select the Snap Drag tool, access the Numeric options panel, and set the Drag Set option to All Points. Modeling | 173 UVs 5. Click and drag on any of the selected points and move it near the corre- sponding point on the other group. 6. As a final step, apply the Merge Points command using the Automatic option and checking Keep 1-Point Polygons. 174 | Chapter 4 UVs Here’s the result of the operation: Versions: 7-8 413 Robin Wood | UVs | Beginner to Intermediate Symmetrical UVs When you have two symmetrical objects that need matching UV maps, such as the two sides of a head or the right and left hands, don’t make two maps. Instead, simply map one, then select the matching part and delete it. Mirror the Modeling | 175 UVs mapped part without merging points, and use Flip UVs to flip the UVs on the map. Then drag the new portion to the correct place on the map, and merge the points. Both halves of the object are now mapped, with a minimum of work. Versions: 6.5-8 414 Jonny Gorden | UVs | Beginner Editing UV Maps To edit UV maps using symmetry: 1. In the Map tab, select Transform UV. 2. Check Offset, enter –50% for U, and press OK. 3. Turn on Symmetry and edit your points. 4. When you’ve finished editing, select Transform UV again and enter 50% for U to restore the map to within the UV boundary. Versions: 6-8 415 Leigh van der Byl | UVs | Beginner Successfully Working with Discontinuous UV Maps UV maps created in LightWave are discontinuous by nature. This means that when the polygons in your model are unwrapped and flattened to create the UV map, areas where the model has become separated by the unwrapping process will remain locked in place to ensure that they do not become very badly unaligned during the editing process. You’ll notice that some points of the UV map are not visible and cannot be moved around when you move surrounding polygons or points around. This generally prevents you from editing your UV maps properly, so you need to unlock these points so that they can move around freely. To be able to do this you need to disconnect the polygons within your UV map from one another while maintaining the points that connect them on each polygon. We use the Unweld command (Ctrl+u, or Detail>Points>Unweld) to do this. Unwelding the points creates multiple copies of those selected points (or of all the points in the model if none are selected) so that none are shared by two polygons. Each polygon is given its own copy of the selected vertices, making this command essential to being able to edit discontinuous UVs correctly and efficiently. Of course, you mustn’t forget to merge (hit “m” or Construct> Reduce> Merge Points) the points again once you are finished editing. Versions: 6.5-8 416 Jonny Gorden | UVs | Beginner Editing UV Map Points Once you’ve created your UV map using a default projection, you should edit the points of the map so that the polygons are roughly the same aspect and scale as the model. Editing the points also allows you to fix overlapping poly - gons. If you base your UV map on a cylindrical or spherical projection, make 176 | Chapter 4 UVs [...]... the color information getting in the way and confusing what you’re really seeing Versions: All 46 3 Gerald Abraham | General Tips | Beginner Making Changes When making fine surfacing or lighting adjustments, it’s a good idea to make only one change at time Versions: All 46 4 William “Proton” Vaughan | General Tips | All Levels The Power of Surface Borders When drawing polygon edges in a render, you have... Eye.Blink_L Modeling | 195 Endomorphs 3 Do the same for the right side, calling the map Eye.Blink_R Versions: 6-8 44 1 Jonny Gorden | Endomorphs | Beginner Smart Morphing Create a scratchpad morph to test how multiple morphs mix together Use the plug-in MorphMap Mixer to perform the mixing Versions: 6-8 44 2 Robin Wood | Endomorphs | All Levels Making a New Morph at a Halfway Point Have you ever wished you had... Airbrush tool could be used to “paint” details into a model by simply swapping the two morphs and airbrushing the effect to bulge or dent the new morph at that point Versions: 7.5-7.5c 196 | Chapter 4 Endomorphs 44 4 Eki Halkka | Endomorphs | Intermediate Creating Sliders with Endomorphs You can create sliders using endomorphs Create a single point in Modeler and add an endomorph to it To make the endomorph... Skelegons Skelegons 44 7 Jonny Gorden | Skelegons | Beginner Click and Drag Make sure you click and drag the first skelegon in a chain; otherwise, you’ll end up with a one-point skelegon at the root of the chain To check for these, select all skelegons using the Polygon Statistics panel, then deselect all twopoint polygons This will leave any one-point skelegons selected Versions: 6-8 44 8 Jonny Gorden |... points!) 45 3 Jonny Gorden | Skelegons | Beginner Convert Skelegons You can add to an existing rig using Convert Skelegons by including only those skelegons you wish to add in your object layer 1 Create the skelegons you wish to add 2 Cut all the skelegons you already have as bones, leaving only the new ones 3 Convert the skelegons to bones 4 Paste back the skelegons you previously cut Versions: 6-8 45 4 Jonny... characters and items, because it allows you to place small, subtle visual clues on your models that help to create a story for them — Leigh van der Byl 201 202 | Chapter 5 General Tips General Tips 46 0 Larry Shultz | General Tips | Advanced Fake Lights Sometimes when I need to create lighting effects and I don’t want to increase the number of lights I’m using or I want to create the effect of caustics... falloff, for example, can create very believable water caustics without the render hit Versions: 5-8 46 1 Jonny Gorden | General Tips | Beginner Bump Map Trick Use your bump map on a low strength in your diffuse and specular channels to accentuate the detail Versions: 6-8 46 2 Lee Stranahan | General Tips | All Levels Do Your Bump Mapping Before Your Color Mapping If you plan to apply both a bump and... the object 43 5 William “Proton” Vaughan | Endomorphs | All Levels Endomorphs Can Fix… Endomorphs can be a great tool for fixing problem areas in deformation Shoulders and hips come to mind When an arm or leg is moved, it can give you some odd creases Use an endomorph to adjust the points and just morph to the endomorph when the animation calls for it Versions: All 1 94 | Chapter 4 Endomorphs 43 6 Todd... skelegons in the viewport perpendicular to the pitch of the bone Versions: 6-8 44 9 Todd Grimes | Skelegons | Intermediate Drawing Skelegons Always draw skelegons in the viewport on which you’d like that bone’s local y-axis to be The y-axis for the bones is the axis along which the pitch channel will be aligned in the layout Versions: 6-8 45 0 Todd Grimes | Skelegons | Intermediate Edit Skelegons Use the Edit... http://www.dstorm.co.jp/dslib/map.html#MorphMapMixer 43 9 Todd Grimes | Endomorphs | Beginner Separate Phonemes Separate phonemes (mouth shapes associated with vowels and consonants for lip sync) from other mouth expressions such as smile, grin, frown, and scream Having separate groups for these shapes will make it easier to animate lip sync with the facial performance Versions: 6-8 44 0 Jonny Gorden | Endomorphs | Beginner . using the Automatic option and checking Keep 1-Point Polygons. 1 74 | Chapter 4 UVs Here’s the result of the operation: Versions: 7-8 41 3 Robin Wood | UVs | Beginner to Intermediate Symmetrical UVs When. you mustn’t forget to merge (hit “m” or Construct> Reduce> Merge Points) the points again once you are finished editing. Versions: 6.5-8 41 6 Jonny Gorden | UVs | Beginner Editing UV Map. ensuring they will meet up perfectly. 180 | Chapter 4 UVs Some 3D painting packages, such as Maxon’s BodyPaint and Right Hemi - sphere’s Deep Paint 3D, have tools specifically for covering up seams