3ds Max 2012 Bible - Kelly L. Murdock [350]
Mapping Modifiers
Among the many modifiers found in the Modifiers menu are several that are specific to material maps. These modifiers are mainly found in the UV Coordinates submenu and are used to define the coordinates for positioning material maps. These modifiers include the UVW Map, UVW Mapping Add, UVW Mapping Clear, UVW XForm, MapScaler (WSM), Projection, Unwrap UVW, Camera Map (WSM), and Camera Map.
Cross-Reference
The Projection modifier is used to create normal maps and is covered in Chapter 34, “Creating Baked Textures and Normal Maps.” •
UVW Map modifier
The UVW Map modifier lets you specify the mapping coordinates for an object. Primitives, Loft Objects, and NURBS can generate their own mapping coordinates, but you need to use this modifier to apply mapping coordinates to mesh objects and patches.
Note
Objects that create their own mapping coordinates apply them to Map Channel 1. If you apply the UVW Map modifier to Map Channel 1 of an object that already has mapping coordinates, then the applied coordinates overwrite the existing ones. •
You can apply the UVW Map modifier to different map channels. Applying this modifier places a map gizmo on the object. You can move, scale, or rotate this gizmo. To transform a UVW Map gizmo, you must select it from the subobject list. Gizmos that are scaled smaller than the object can be tiled.
Many different types of mappings exist, and the parameter rollout for this modifier lets you select which one to use. The Length, Width, and Height values are the dimensions for the UVW Map gizmo. You can also set tiling values in all directions.
Note
It is better to adjust the tiling within the UVW Map modifier than in the Material Editor because changes in the Material Editor affect all objects that have that material applied, but changes to a modifier affect only the object. •
The Alignment section offers eight buttons for controlling the alignment of the gizmo. The Fit button fits the gizmo to the edges of the object. The Center button aligns the gizmo center with the object's center. The Bitmap Fit button opens a File dialog box where you can align the gizmo to the resolution of the selected bitmaps. The Normal Align button lets you drag on the surface of the object, and when you release the mouse button, the gizmo origin is aligned with the normal. The View Align button aligns the gizmo to match the current viewport. The Region Fit button lets you drag a region in the viewport and match the gizmo to this region. The Reset button moves the gizmo to its original location. The Acquire button aligns the gizmo with the same coordinates as another object.
Figure 33.1 displays a brick map applied to an umbrella using spherical mapping.
Tutorial: Using the UVW Map modifier to apply decals
After mapping coordinates have been applied either automatically or with the UVW Map modifier, you can use the UVW XForm modifier to move, rotate, and scale the mapping coordinates.
Most objects can automatically generate mapping coordinates—with the exception of meshes. For meshes, you need to use the UVW Map modifier. The UVW Map modifier includes seven different mapping options. Each mapping option wraps the map in a different way. The options include Planar, Cylindrical, Spherical, Shrink Wrap, Box, Face, and XYZ to UVW.
FIGURE 33.1
The UVW Map modifier lets you specify various mapping coordinates for material maps.
In this tutorial, you use the UVW Map modifier to apply a decal to a rocket model. Zygote Media created the rocket model.
To use the UVW Map modifier, follow these steps:
1. Open the Nasa decal on rocket.max file from the Chap 33 directory on the CD.
This file includes a model of a rocket with the appropriate materials applied. The Chap 33 directory on the CD also includes a 300 × 600 image of the word NASA in black capital letters on a white background. The background color of this image was set to be transparent, and the image was saved as a .gif.
Note
The GIF format, typically used for Web pages, can easily make areas of the image