3ds Max 2012 Bible - Kelly L. Murdock [222]
Cross-Reference
The Render to Texture dialog box and Normal maps are covered in more detail in Chapter 34, “Creating Baked Textures and Normal Maps.” •
Raytrace map
The Raytrace map is an alternative to the raytrace material and, as a map, can be used in places where the raytrace material cannot.
Cross-Reference
Check out Chapter 47, “Rendering with mental ray and iray,” for more on the Raytrace materials and maps. •
Reflect/Refract map
Reflect/Refract maps are yet another way to create reflections and refractions on objects. These maps work by producing a rendering from each axis of the object, like one for each face of a cube. These rendered images, called cubic maps, are then projected onto the object.
These rendered images can be created automatically or loaded from pre-rendered images using the Reflect/Refract Parameters rollout. Using automatic cubic maps is easier, but they take considerably more time. If you select the Automatic option, you can select to render the First Frame Only or Every Nth Frame. If you select the From File option, then you are offered six buttons that can load cubic maps for each of the different directions.
In the Reflect/Refract Parameters rollout, you can also specify the Blur settings and the Atmospheric Ranges.
Thin Wall Refraction map
The Thin Wall Refraction map simulates the refraction caused by a piece of glass, such as a magnifying glass. The same result is possible with the Reflect/Refract map, but the Thin Wall Refraction map achieves this result in a fraction of the time.
The Thin Wall Refraction Parameters rollout includes options for setting the Blur, the frames to render, and Refraction values. The Thickness Offset determines the amount of offset and can range from 0 through 10. The Bump Map Effect value changes the refraction based on the presence of a bump map.
Tutorial: Creating a magnifying glass effect
Another common property of glass besides reflection is refraction. Refraction can enlarge items when the glass is thick, such as when you look at the other side of the room through a glass of water. Using the Thin Wall Refraction map, you can simulate the effects of a magnifying glass.
To create a magnifying glass effect, follow these steps:
1. Open the Magnifying glass.max file from the Chap 17 directory on the CD.
This file includes a simple sphere with a Perlin Marble map applied to it and a magnifying glass modeled from primitive objects.
2. Choose Rendering⇒Material Editor ⇒Slate Material Editor (or press the M key) to open the Material Editor.
3. Locate and double-click the Thin Wall Refraction option in the Material/Map Browser to add a node to the Node View. Drag a connection wire from the output socket, drop it anywhere on the Node View, and then select the Materials/Standard material from the pop-up menu and the Refraction channel from the parameters pop-up menu. This adds a standard material node to the Node View and connects the Thin Wall Refraction node to the material's Reflection parameter.
4. Double-click the Thin Wall Refraction node to open its parameters in the Parameter Editor. In the Thin Wall Refraction Parameters rollout, set the Thickness Offset to 10 to increase the amount of magnification.
5. Drag the output socket for the material node and drop it on the magnifying glass object in the viewport to apply the material to the object.
Figure 17.34 shows the resulting rendered image. Notice that the texture in the magnifying glass appears magnified.
FIGURE 17.34
The Thin Wall Refraction map is applied to a magnifying glass.
Using the Maps Rollout
Now that you've seen the different types of maps, we'll revisit the Maps rollout (introduced in Chapter 15), shown in Figure 17.35, and cover it in more detail.
The Maps