enhancing models with materials

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460 | CHAPTER 9 enhanCInG Models wIth MaterIals Selecting Two-Sided Materials The 2-Sided option is sometimes needed to correct improper normal orientation in models that have been imported from other 3D programs, particularly CAD programs. This option isn’t usually as critical for models built entirely within 3ds Max because the surfaces are usually facing in the correct direction and single-sided materials generally are sufficient. 6. Click the None button next to the Diffuse Map label, and in the Material/Map Browser open the Maps group and then the Standard group. Then double-click Bitmap. 7. In the Select Bitmap Image File browser that opens, navigate to the C:\Program Files\ Autodesk\3ds Max Design 2011\maps\ArchMat folder. Your actual folder path may vary. 8. Double-click the Woods&Plastics.FinishCarpentry.Urethane.jpg file to add it to the Diffuse Map channel of the current material and return to the Material Editor. 9. This time, rather than selecting the destination and clicking the Assign Material to Selection button, simply click in the material slot and drag it to the floor as shown in Figure 9.23. A tooltip appears, identifying the object to which the material will be assigned. 10. Render the scene with the floor material added. It’s difficult to see any change because the tile pattern isn’t evident. Try changing the lighting in the scene to see how it affects the materials. Remember that a surface’s rendered appearance is the result of the combination of its geometry, lighting, and materials. Adding Material Mapping Coordinates If you just want to manipulate the color, transparency, and shininess of an object, you can usu- ally create or use a material that doesn’t use bitmaps to simulate a texture. Once you start to add a texture using bitmaps, you’ll need to specify how that texture is applied to the object. You’ll want to tell 3ds Max the size of the texture in relation to the object, as well as its orientation on Figure 9.23 Assigning a mate- rial by dragging it into the scene edItInG MaterIals | 461 the object. For example, you wouldn’t want the brick pattern to appear with its courses running vertically, as in the example shown in Figure 9.24, nor would you want the brick pattern to be quite so large. To control how materials are applied to objects, you’ll want to know how to use the UVW Map modifier. This modifier lets you precisely control the way a material is placed on an object. In the next exercise, you’ll add the modifier to the condo floor to establish the orientation and size of the Floor_Condo_Wood material in relation to the object. What Does UVW Mean? The UVW in the name UVW map refers to the coordinates of a material map. They indicate the direc- tion of a map in a way similar to the XYZ Cartesian coordinates with which you’re already familiar. The letters UVW differentiate map coordinates from the standard XYZ-coordinate designation and were chosen simply because they precede XYZ in the alphabet. UVW map coordinates need to be differentiated from XYZ-coordinates because, although they indi- cate direction similar to XYZ-coordinates, they are in relation to the length and width of the image map regardless of the object’s orientation in space. UVW-coordinates also don’t treat measured distances in the same way. In a Cartesian coordinate system, distances are measured at specific intervals of feet, meters, or whatever measurement system you’re using. UVW map coordinates, on the other hand, are measured as a percentage of width and height of a surface. Instead of feet or meters, UVW maps use real values from 0 to 1. The value used represents a percentage of the overall width of the surface being mapped, with 1 being equal to 100 percent of the surface width. Because the coordinate values in a UVW map are based on a percentage, a U value of 0.5 can repre- sent a measured distance that’s different from a V value of 0.5. For example, imagine a rectangular surface with a UVW-coordinate system whose origin is the lower-left corner of the rectangle. The upper-right corner of the rectangle would then be the coordinate 1,1, even though the length and width of the rectangle are not equal to each other. This may seem a bit odd at first, but if you consider that material maps are used to match an image to a surface, you begin to see the rationale behind the UVW map system. The relationship between a map and a surface is more important than their actual dimensions. You can think in terms of “What percentage of the surface does the map cover?” rather than “How many square inches does the map cover?” Figure 9.24 A brick wall with the brick courses running vertically and at a large scale 462 | CHAPTER 9 enhanCInG Models wIth MaterIals A UI Discrepancy Oddly, the modifier in the Modifier List drop-down is named UVW Map although UVW Mapping appears in the modifier stack. 1. Right-click the Top viewport; then use the Zoom Extents tool to zoom out so that your view looks similar to Figure 9.25. 2. Click the Select by Name tool and use the Select from Scene dialog box to select the Floor407 object. 3. Click the Modify tab of the Command panel, expand the Modifier List drop-down, and then assign the UVW Map modifier to the Floor407 object. 4. In the Parameters rollout, make sure Planar is selected as the mapping type and then deselect the Use Real-World Map size option at the bottom of the Mapping group. Turning this option off allows you to manually control the number of times the map repeats itself. 5. In the Alignment section, click the Fit button to adjust the gizmo size to match the size of the floor. Let’s take a moment to study the UVW Map gizmo. It has one green edge and a small line sticking out on one side. You will have to expand the UVW Mapping modifier and select the gizmo to see the colors. Figure 9.26 gives you a clear picture of what the gizmo looks like. If the map is oriented incorrectly, use the Select and Rotate tool to rotate it properly. The colored edge and the small line help you orient the UVW Mapping gizmo on an object by showing you which way is up and which directions are left and right: the short line extending from the frame indicates the top of the image and the green edge denotes the right side. You’ll get a more detailed look at the UVW Mapping gizmo after the cur- rent exercise. You can increase the amount of tiling two ways: decrease the size of the gizmo or increase the Tile values in the Parameters rollout. Let’s continue by adjusting the Tile values to reduce the size of the material on the Floor407 object. Figure 9.25 The condo in the Top viewport edItInG MaterIals | 463 If you were to render the scene now, the woods&plastics.finishcarpentry.urethane .jpg image would be stretched across the floor a single time and appear pixelated. You’ll want to scale the Floor_Condo_Wood material to a size that’s more in line with the size of the floor object by instructing 3ds Max to repeat, or tile, the material several times. Continuing from the previous steps, you will use the UVW Map modifier to improve the appearance of the floor’s texture map. 6. In the Mapping section, enter 20 in both the U Tile and V Tile input fields. This causes any material assigned to the floor object to repeat itself 20 times within the boundary of the UVW Mapping gizmo. 7. Render the scene. The linear pattern of the image map becomes apparent, as shown in Figure 9.27. There is one final step that you are going to do to make the floor material pop just a little more. The Architectural materials’ Intensity parameter controls the brightness of the material. In the Intensity channel you’ll use the same map that you used in the Diffuse color channel. Figure 9.26 The UVW Mapping gizmo assigned to the Floor407 object Figure 9.27 Changing the U and V Tile settings causes the diffuse color map to repeat over the surface of the object. 464 | CHAPTER 9 enhanCInG Models wIth MaterIals Removing Bitmaps from Materials There are several methods for removing a map from a material. While the map’s parameters are visible (the Coordinates and Bitmap Parameters rollouts), you can click the Reset Map/Mtl to Default Settings button in the Material Editor toolbar and then click Yes in the warning dialog that opens. Finally, you can click and drag any button labeled None in the Maps rollout and drop it over a button containing a map name to clear the map slot. 8. Click the Diffuse Map button and drag the map to the Intensity button in the Special Effects rollout, as shown in Figure 9.28. 9. In the Instance (Copy) Map dialog box that appears, choose Instance, and then click OK. Using the instance option, changes made to one map are immediately made to the other. 10. Render the scene once more, and you’ll see that the wood strips are more defined. Exposing All Available Sample Slots If your Material Editor displays only 6 or 15 samples, don’t worry. You can access the remaining slots by using the vertical and horizontal scroll bars around the slots, or you can expose all of the slots at one time. To expose all of the slots, click the Options button on the Material Editor’s vertical toolbar to open the Material Editor Options dialog box. Figure 9.28 Dragging a map from one channel to another understandInG MaPPInG CoordInates | 465 In the Slots area at the bottom of the dialog box, select the 6 × 4 radio button. Click OK to accept the changes; the Material Editor updates to show all 24 sample slots. There is no practical limit to the number of materials in a scene—the number of materials is limited only in the Material Editor. Understanding Mapping Coordinates The UVW Map modifier you added in the previous exercise told 3ds Max the size, location, and orientation of the material on the object to which it is assigned. At render time, the image is usu- ally applied to the object in a repeated, or tiled, fashion. You can also set a material to apply the bitmap just once. In this section, you’ll take a closer look at the UVW Map modifier. What Happens When You Add the Mapping Coordinates The UVW Mapping gizmo you saw in the previous exercise is a visual representation of the mapping coordinates. Its shape and color are aids in helping you see the bitmap’s orientation more clearly. As mentioned earlier, the small line at the top of the icon represents the top of the bitmap, while the green shows the right side. These indicators can tell you at a glance whether the bitmap image of the material you are using is upside down or backward in relation to the object to which the coordinates are being applied, as shown in Figure 9.29. Figure 9.29 The UVW Mapping gizmo in relation to a material bitmap Point Green edge The UVW Mapping gizmo 466 | CHAPTER 9 enhanCInG Models wIth MaterIals The orientation of the bitmap in the preceding exercise is really not that important, but it can be important for texture maps that do have a specific orientation, such as a brick pattern, or for a single image, such as a wine label or a road sign. The UVW Mapping gizmo shows the approxi- mate size of the bitmap in relation to the object to which it is being applied. When the model is rendered, multiple copies of the image are applied over the entire surface of the object, like tiles on a kitchen counter. Figure 9.30 shows another way that the gizmo affects the appearance of a material. You see a brick wall with the gizmo rotated. The bricks are angled and aligned with the UVW Mapping gizmo. Adjusting the UvW Mapping Gizmo You have a number of options for controlling the size, shape, and orientation of the UVW Mapping gizmo. These will be crucial to your ability to place materials accurately on an object or an individual face. Here are descriptions of the Alignment group options as they appear in the Command panel: Manipulate Activates the Select and Manipulate tool. You can also access this tool by clicking the Select and Manipulate icon on the Main Toolbar. The Manipulate option causes the gizmo to turn green and a cursor to appear like the Select cursor when it is over the edges of the UVW Mapping gizmo. Using the Select and Manipulate transform, you can click and drag the edges of the UVW Mapping gizmo to define the exact size and location for the bitmap. Region Fit Lets you fit the UVW Mapping gizmo to a specific rectangular area. This is useful for situations where you want a texture map to fit exactly over a specific region of an object. When you choose this option, you can select two points to define the two diagonal corners of the UVW Map gizmo. The process is similar to selecting a zoom region or creating a rectangle. Because this option lets you select any two points, it will stretch and distort the UVW Map gizmo in either the X- or Y-axis. To orient the UVW Map gizmo rightside up, pick two points over the region starting with the lower-left corner (see Figure 9.31). Figure 9.30 A sample brick wall with the UVW Mapping gizmo rotated 30 degrees The UVW Mapping gizmo rotated understandInG MaPPInG CoordInates | 467 Bitmap Fit Adjusts the UVW Map gizmo’s proportion to fit the shape of a particular bitmap image. This option uses the current UVW map size and alters the proportions to fit the bit- map proportions. The option is helpful if you want the bitmap to be displayed accurately in its original form. It also helps if you want a better idea of the bitmap’s shape as you assign the mapping coordinates to objects. View Align Aligns the UVW Map gizmo to a viewport. This option can help you locate a UVW map or quickly align it to a viewport. Fit Stretches the UVW Map gizmo over the surface of an object to make it fit exactly. Center Centers the UVW Map gizmo on an object’s surface. Acquire Sets the UVW Map gizmo to match the mapping coordinates of an object that already has mapping coordinates assigned to it. Reset Resets the UVW Map gizmo to the 3ds Max default size and orientation. Normal Align Aligns the UVW Map gizmo to the normal of a surface of the object to which the mapping is attached. co n t r o l l i n G t h e ti l i n G eF F e c t When you added the Floor_Condo_Wood material to the floor object and increased the number for the U and V Tile parameters, the wood striping pattern appeared at a smaller scale and was repeated over the entire surface of the floor in a rectangular array. This repetition of the map is called tiling. If you’ve ever experimented with the Windows desktop wallpaper, you may already be familiar with the idea of tiling. Tiling is on by default, but you can turn it off for situations when you want only a single image to appear over the surface. Figure 9.32 portrays the same brick wall shown in Figure 9.31, but this time the Tile option is turned off. The brick pattern appears only in the region defined by the UVW Map gizmo. The rest of the wall surface is rendered based on the Basic Parameters rollout settings of ambient, diffuse, and specular color. Figure 9.31 A Region Fit UVW Map gizmo is placed on a wall in the Front viewport (left). A rendered view is shown with the UVW Map gizmo superim- posed on the view (right). The location of the UVW Mapping gizmo in relation to the final rendered surface Drag to form a region. Then click here.Click here first. 468 | CHAPTER 9 enhanCInG Models wIth MaterIals The tile settings are located in the Material Editor and can be controlled or turned on/off there as well. Here’s how to locate the tiling parameters: 1. Open the Material Editor. 2. With the Floor_Condo_Wood material selected, scroll down the list of rollouts and open the Physical Qualities rollout if it isn’t already open. 3. Locate the map you want to adjust; then click its button. For example, for the Floor_Condo_ Wood material, click the Diffuse Map button labeled woods&plastics.finishcarpentry .urethane.jpg (the button displays as much of the name as it can). The parameters for that particular map display in the Material Editor. 4. Open the Coordinates rollout and locate the Tile check boxes, as shown in Figure 9.33. You can click the U and V Tile check boxes to turn off tiling. Don’t change this setting for your condo model, however—you want to keep the tile setting turned on. un d e r S t a n d i n G t h e di F F e r e n t tY P e S o F ma P P i n G When you first apply the UVW Map modifier to an object, 3ds Max uses its default planar map type. As you might guess from its name, this map type maps the bitmap image to a plane, or flat surface, as shown in Figure 9.32. This option projects a flat image onto a surface. The orien- tation of the UVW Map gizmo in relation to the object affects the appearance of the material. Figure 9.34 shows how the same texture map can be projected onto a box with different effects. As you can see from Figure 9.34, you aren’t limited to using a planar map that’s parallel to the surface you are mapping. You can create some interesting effects by reorienting the UVW Map gizmo. The streaking that you see on the boxes is the color of the edge pixels projected across the faces that run perpendicular to the gizmo. Figure 9.32 The brick wall ren- dered with the Tile option turned off Figure 9.33 The Tile options for a selected bitmap understandInG MaPPInG CoordInates | 469 Figure 9.34 A box with map- ping coordinates oriented in dif- ferent ways. The texture map is identical in each example. But what do you do if you want to map an image to a cylindrical or spherical object? 3ds Max offers several other mapping types to facilitate mapping to nonplanar surfaces. If you look at the Parameters rollout for the UVW Mapping modifier, you see the radio button options shown in Figure 9.35. The cylindrical map curves the bitmap into a cylindrical shape and then projects the map outward from the center of the cylinder. Naturally, you would use this type of mapping on cylindrical objects. You will want to place such a map in the center of the object. The Cap option places the map on the end caps of the gizmo, similar to the Planar option. When you choose this map, the UVW Mapping gizmo changes to a cylindrical one, as shown in Figure 9.36. You would then place this map in the center of a cylindrical object and assign it to the object. You can also distort the map by moving the UVW Mapping gizmo closer to one side or the other or rotating the map so it isn’t aligned with the object. Figure 9.35 Mapping options [...]... Figure 9.73 Two renderings with people used as bitmaps The image to the left has distorted the people | Chapter 9 Enhancing Models with Materials 490  To do this, choose the Bitmap Fit alignment option under the Parameters rollout of the UVW Map modifier, as shown in Figure 9.74 Figure 9.74 Use the Bitmap Fit option to adjust the aspect ratio of the image Locate the bitmap file associated with the material... worked with the condo scene Let’s go back and explore the option of placing more than one material on an object Assigning Materials to Parts of an Object As you work with imported AutoCAD files or complex models in 3ds Max, you’ll almost certainly find yourself faced with the situation where you want to add a material to only a single surface, or group of polygons, of an object This is the situation with. .. Exploring the Autodesk Materials So far you’ve seen convincing surfaces in your renderings using the Architectural materials This is because the materials you have made account for light reflecting off surfaces or passing through translucent surfaces (refraction) New to 3ds Max Design 2011 is the inclusion of the Autodesk Materials, a set of approximately 1,200 materials shared with all Autodesk 2011... mapped on the Path object | Chapter 9 Enhancing Models with Materials 480  15 Navigate to the Coordinates rollout of the checker texture Turn off Real-World Scale, and adjust the U and V tiling while observing the effect Changing the V tiling to 12 clearly shows the checker following the path contours now, as in Figure 9.55 16 To exchange the checker pattern with a bitmap, click the Material Type... Material Editor  Slate Material Editor Alternatively, on the Main Toolbar there’s a flyout | Chapter 9 Enhancing Models with Materials 482  that lets you choose between Compact and Slate Material Editors if you’d rather use an icon 2 Right-click in the View1 window of the Slate Material Editor, and choose Materials  metal ray  Arch & Design, as shown in Figure 9.58 3 Right-click the top bar of the material,... Figure 9.62 Changing the material Preview Object Type | Chapter 9 Enhancing Models with Materials 484  11 Right-click the material node, and click Open Preview Window to see a larger version of a material sample This opens a small dialog box, which is similar to the Magnify window of the Compact Material Editor, which can be resized and which updates with any parameter changes made to the material, as shown... | Chapter 9 Enhancing Models with Materials 486  3 Click the Create tab in the Command panel; then click the Geometry button if it isn’t already highlighted 4 Click Plane, and then, in the Perspective viewport, create the plane Use the Length and Width parameter options to set the length to 24´ and the width to 24´ 5 Give the plane the name Tree001 You can also use Box primitives (with 0 depth)...470  | Chapter 9 Enhancing Models with Materials Figure 9.36 A view of the UVW Mapping gizmo when using the Cylindrical mapping type, along with a sample of an object that uses this mapping type Bitmap Cylindrical UVW Map gizmo Rendering Spherical mapping curves the bitmap into... Chapter 9 Enhancing Models with Materials Just below the Mapping radio buttons in the Parameters rollout are the Length, Width, and Height input boxes As you might guess, these options let you enter numeric values for the length, width, and height of the UVW Map gizmo Their spinners also let you graphically adjust the size of the gizmo Finally, if you want to modify the tiling of the bitmap image within... Editor should look like Figure 9.75 Figure 9.75 The Cabinet_ Wood_Glass_Multi material in the Compact Material Editor | Chapter 9 Enhancing Models with Materials 492  Notice how, at the top level of the Multi/Sub-Object Material, the object in the sample slot has the sub -materials applied to different portions of its surface Now let’s copy the current submaterial to additional slots and add the material . 460 | CHAPTER 9 enhanCInG Models wIth MaterIals Selecting Two-Sided Materials The 2-Sided option is sometimes needed to correct improper normal orientation in models that have been imported. the map cover?” Figure 9.24 A brick wall with the brick courses running vertically and at a large scale 462 | CHAPTER 9 enhanCInG Models wIth MaterIals A UI Discrepancy Oddly, the modifier. color map to repeat over the surface of the object. 464 | CHAPTER 9 enhanCInG Models wIth MaterIals Removing Bitmaps from Materials There are several methods for removing a map from a material.