Maya 4.5 Fundamentals

This section describes the major material types, as shown in Figure 9.2.

Lambert

Lambert is a flat material type that yields a smooth look without specular highlights. It calculates without taking into account surface or reflectivity, which gives a matte, chalk-like appearance. Lambert material is ideal for surfaces that don't have highlights: pottery, chalk, matte paint, and so forth. By default, any newly created object is assigned the Lambert shader. If the object should have highlights, however, it's a good idea to assign a shader such as Phong or Blinn. It helps to see highlights during the modeling stage to see whether they are breaking across an object (indicating a seam in the surface).

Phong

The Phong material takes into account specular reflectivity to create highlights across an object surface. The algorithm can be customized for surfaces such as plastic, porcelain, and glazed ceramic.

tip

If you notice that the highlights of a surface seem to flicker in your animation, or you see a "ropy" appearance from line to line, switch to a Blinn material type, which has smoother highlights. This problem can also occur when using bump mapping.

PhongE

PhongE is a faster rendering version of Phong that yields somewhat softer highlights than Phong. If you want highlights on the model's surface, some artists prefer to use regular Phong for intense highlights and Blinn for everything else.

Blinn

The Blinn material calculates highlights on surfaces similarly to Phong; however, Blinn can achieve a more accurate representation of the soft tinted highlights you see on metallic surfaces. Because Blinn is a versatile material type and doesn't cause flickering with bump maps, it's the main material type used in these tutorials.

Anisotropic

The Anisotropic material type stretches highlights and rotates them based on the viewer's position. Objects with many parallel micro-grooves, such as brushed metal, reflect light differently, depending on how the grooves are aligned in relation to the viewer. Anisotropic materials are ideal for materials such as hair, feathers, brushed metal, and satin.

Ramp Shader

The Ramp Shader material consists of built-in ramp graphs to offer more advanced control and simplify the shader network. Almost every attribute for this shader offers three basic settings. The first, Selected Position, sets the location of a color swatch within the ramp. Next, Selected Color sets the color of the currently selected swatch. The third setting, Interpolation, controls how the swatches blend between one another.

Ocean Shader

The Ocean Shader material has several items in the shader's attributes that control how the material behaves over time, and it has graphs to add detail to the base shader. This avoids manually creating complex networks that could result in long render times. Attributes include Wave Speed, Wave Height, Wave Turbulence, and Wave Peaking. These main attributes contain the same graph controls as the Ramp Shader material.

The Others: Layered Shader, Shading Map, Surface Shader, and Use Background

The four remaining material types are for more advanced purposes, so this section just offers an overview of their purpose. The Layered Shader lets you combine several materials to create a more complex material. For example, if you want chrome polka dots on a wood surface, you can simply use a polka dot mask in a Layered Shader material and then bring in your already completed chrome and wood materials.

The Shading Map material is primarily designed to let you get a "cel" look in 3D, like typical animated cartoons. You can use this shader for a 2D painted-in look rather than smoothly shaded 3D.

The Surface Shader is used when you want to control a material's color, transparency, and glow with something else in Maya. For example, you could link color to any object's XYZ position, and the material would then change colors as that object moved around the scene.

The Use Background shader cuts a "hole" in the image's alpha channel where objects with the material appear. This material is useful for combining separately rendered images in a compositing program to create the final results (for more information, check out Chapter 16, "Your Next Steps: Efficiency and Artistry"). CG artists usually do this to divide a large, complex animation into more manageable parts or to combine 3D animation with photographed/filmed live action.