INSIDE 3DS MAX® 7 [Electronic resources] نسخه متنی

Collapsing procedural objects into Editable Meshes, Patches, Poly objects, or NURBS objects preserves their original mapping coordinates, but if you apply a UVW Map on top of these objects and then collapse them again, your original Procedural mapping coordinates will be lost.

The Shell modifier (under Object-Space Modifiers) is different from the Shell material. The former allows you to create "thickness" in the walls of your 3D geometry; the latter is used to bake procedural textures into a single bitmap.

1.

From the DVD, load the file Object Space vs World Space.max (Figure 10.11).

2.

Scroll the Time Slider bar to see two spheres that travel across the screen in front of a checkerboard background. Both spheres have UVW Map modifiers applied, with Spherical mapping coordinates.

3.

Open the Material Editor, and inspect the materials in the scene. There are two different materials (one for each sphere), both using the Checker map. Another Checker map (with Screen mapping coordinates) forms the Environment Background image.

4.

Select the first material (Object-Space Mapping), and open its Diffuse Color map slot, loaded with the Checker map. Under the Coordinates rollout, you'll see that the Texture radio button is checked and that the Mapping coordinates are set to Explicit Map Channel.

5.

Select the second material (World-Space Mapping), and open its Diffuse Color map slot. Under its Coordinates rollout, you'll see that the Environment button is checked, with the Mapping coordinates set to Screenthe same parameters used in the background map.

6.

Activate the Camera01 viewport, and render a still image of this scene on frame 0 (Figure 10.12). You'll see that the top sphere has a distinctive checker pattern on it that wraps around the object. However, the bottom sphere blends into the background. Its mapping coordinates match the background's coordinates, so it is virtually invisibleonly its shadow helps you discern the sphere's shape.

7.

From the DVD, select the file OSM vs WSM 1.avi. This 320-by-240 .avi shows the spheres flying through the scene. The movement clearly shows how the object-space coordinates on the top sphere move with the sphere, while the sphere below appears to move "through" the background texture.

8.

Now return to the Material Editor. Select the second (World-Space) material, and click the Go To Parent button to go to the top level of this material. Under the Blinn Basic Parameters rollout, drag the Self-Illumination slider from 0 to 100.

9.

Activate your Camera01 viewport again, and render a test image. You'll notice that the bottom sphere completely disappears. It is mapped with the background image and there are no shadows on it, so it's effectively invisible.

1.

Return to the Material Editor, go to the WSM material, open its Checker diffuse map, and under the Checker Parameters rollout, click the Swap button to switch the black and white color swatches. Now render another test image. Result: You see that the sphere appears to invert the background image texture, but only where the sphere appears "over" the background image.

2.

Return to the Material Editor again, and in the WSM material, click the Swap button to return the color swatches to their original positions. Under the Coordinates rollout, change Blur Offset from 0.0 to 0.1, then render another test image of the Camera01 viewport. Result: The bottom sphere appears to blur the background map, but again, only where the sphere appears "over" the background image.

3.

Return to the Material Editor once more, go to the WSM material, turn Blur Offset back to 0.0, and click the Color #1 swatch to open the Color Selector. Change the black Color #1 swatch to RGB coordinates (0, 0, 255), bright blue; then select the Color #2 swatch and change it to RGB (255, 255, 0), bright yellow.

4.

Render the Camera01 viewport. The colors that you switched on the foreground sphere (while retaining identical mapping coordinates on the background) cause the self-illuminated bottom sphere to "colorize" the background over which it passes. You can also reverse this effect: Make the background Checker pattern colorful, but have the sphere appear to turn it black and white.

To properly match the anti-aliasing and texture filtering of the background image (or background plate, in VFX jargon), you should pick the Plate Match/MAX 2.5 filter from the Render tab of the Render Scene dialog and use that for your final rendering.

1.

Go to Command panel > Create tab > Standard primitives and create a Box primitive in the scene of 100 units on each side.

2.

Click the Modify tab, make sure the box is selected, and from the Modifiers panel, apply an Edit Mesh modifier to the box.

3.

Go to the Edit Mesh modifier's Polygon sub-object level, select the top polygon of the box (in the Perspective viewport, say), and then go to the Surface Properties rollout in the Modify panel. Under Material, the Set ID number should be set to 1 (Figure 10.13). Click other faces on the box, and notice how the Material ID number changes. From this rollout you can also modify the ID numbers that 3ds max 7 automatically assigns to the box faces.

4.

The job of assigning a different map to each face on this box is where the Multi/Sub-Object material comes in. From the DVD, load the file Box Multi-Sub Object Mapping.max. When the file loads, select the box, open the Material Editor, and take a look at the Material Settings.

The first material slot contains the initial Multi/Sub-Object Material used on the box. It has six slots, one per box face and Material ID number (Figure 10.14).

5.

Activate the Camera01 viewport, and render the scene (Figure 10.15). Each of the (self-illuminated) submaterials has one bitmap assigned to its Diffuse Color channel. These bitmaps are simply big, colorful numbers that correspond to each Material ID number.

6.

To create your own Multi/Sub-Object material, click an empty Material slot, click the Standard button, and from the Material/Map Browser, pick Multi/Sub-Object. Discard the existing Standard material unless you began with a Standard material that you want to use as a submaterial in the final Multi/Sub-Object material.

Under the Multi/Sub-Object Basic Parameters rollout, you'll see a default of ten different sub-object materials. Change this number, if desired, by clicking the Set Number button. Then open each Sub-Material slot, and adjust its parameters as needed.

1.

Load the entitled Box Multi-Sub Object Map 2.max from this book's DVD. It is a tesseract-shaped objectbasically, a box with each of its six faces extruded and a MeshSmooth modifier applied to chamfer the corners and sharp edges (Figure 10.16).

2.

Activate the Camera01 or Camera02 viewport, and render the scene (Figure 10.17). This object has a modified version of the previous scene's Multi/Sub-Object material. (The default U and V tiling on some of the submaterial bitmaps has been changed to make them more noticeable on the different parts of the object.)

3.

Select the box, then go to the Modify tab in the Command panel and look at this object's modifier stack. Yow! This object has a complex stack of Edit Mesh and UVW Map modifiers applied to create the final effect. In addition, the UVW Map modifiers are of different typesPlanar, Cylindrical, and Sphericaland are oriented differently on each of their assigned groups of faces.

1.

Go to the Edit Geometry rollout of the Modify panel. Detach the desired group (or groups) of selected faces, and give each new object a unique name. Then apply separate Standard (not Multi/Sub-Object) materials and mapping coordinates to the individual pieces of the original object.

2.

There are times when you can't do this; sometimes you must keep your geometry in one piece. However, you can still cut apart your model, apply materials and mapping coordinates to each piece in turn, and then put the pieces back together.

3.

To rebuild, select one collapsed mesh piece, and from the Modify tab of the Command panel, click the Attach or Attach List button under the Edit Geometry rollout. (Or press the H key to bring up the Select By Name menu to speed up this process.) You'll be given the option of Condensing your existing Materials and ID numbers into a new Multi/Sub-Object material (Figure 10.18).

4.

Go to your Material Editor and modify the components of this new Multi/Sub-Object material as necessary.

1.

Go to Command panel > Create tab > Create a Sphere, setting the radius to 50 units. Increase the Segments value to 60 to make it smooth, and make sure that the Generate Mapping Coordinates check box is checked (as mentioned earlier, it will be checked automatically unless you've deselected it).

2.

Open the Material Editor, click the first material slot, and go down to the Maps rollout. Click the Diffuse Color map button. When the Material/Map Browser appears, double-click Mix.

3.

In the Mix Parameters rollout, next to the Color #1 (black) swatch, click the Maps button, and from the Material/Map Browser, pick Noise. Leave the Noise settings as they are, then click the Go To Parent button to return to the top level of the Mix map.

4.

Click the Maps button next to the Color #2 swatch. From the Material/Map Browser, pick Bitmap. When the Select Bitmap Image File menu appears, go to the DVD and select the file Decal with Alpha.tga, then click the View button. The Decal with Alpha.tga image is a 32-bit image of beveled text.

5.

In the View window, click the Display Alpha Channel button to the right of the three (selected) RGB color component buttons. The text turns pure white. This is the alpha or masking channel for the color text.

6.

Close the View window, and then click Open to load the bitmap image into the Mix map Color #2 slot. Under the Bitmap Parameters rollout, click the Alpha radio button under the Mono Channel Output section of the menu. Then click the Go To Parent button to return to the top level of the Mix map.

7.

Left-click-drag the Color #2 Decal bitmap down to the Mix Amount map slot. When the Copy (Instance) Map menu appears, make sure Instance is selected, then click OK.

8.

Finally, make sure your sphere is selected, click the Assign Material to Selection button, then activate your Perspective viewport and render the scene. Your rendering should look something like the ActiveShade Perspective viewport (Figure 10.19). (Note that, for this illustration, the Show Map in Viewport button of the Decal bitmap is checked so that the bitmap appears also in the Shaded Perspective viewport.)

Now you've got a Decal bitmap floating on top of the underlying Noise texture, but the decal is wrapped around the sphere using the default mapping coordinates. (It's also stretched horizontally, but we'll fix that in a second.) This is not the effect you would normally wantyou more likely want the decal to look like a label applied to a smaller area of the sphere.

9.

To do this, go back to the Material Editor, click one of the Instanced Decal with Alpha bitmap slots to open it, and under the Coordinates rollout, change both the U and the V Tiling from 1.0 to 4.0. Now rerender your scene (Figure 10.20).

Now the decal is smaller on the sphere, but it's also tiled across the surface, and you want it to appear only once. You also want to fix the stretch problem, which is caused by the fact that the square Decal bitmap is made to appear twice as wide by the sphere's inherent Spherical mapping coordinates. Fixing both problems is not difficult.

10.

Return to the Material Editor. Under Coordinates, change the U Tiling from 4.0 to 8.0 (leave the V Tiling of 4.0 unchanged), then uncheck both the U and the V Tile buttons. (Don't check the Mirror buttons, eitherleave them blank as well.) Then rerender your scene (Figure 10.21). The Decal bitmap now appears smaller on the sphere, and the surrounding Tiled images of it disappear, since you unchecked the Tile boxes.

11.

To reposition the decal on the surface of the sphere (while not affecting the underlying Noise texture), return to the Material Editor, and under Coordinates, adjust the U and V Offset values. Changing these will enable you to place the Decal bitmap anywhere you want. Experiment with these settings, and do some test renderings to see the results.