Accessing Other Parameters

In addition to the basic shader parameters, several other rollouts of options can add to the look of a material.

Extended Parameters rollout

The Material Editor includes several settings, in addition to the basic parameters, that are common for most shaders. The Extended Parameters rollout, shown in Figure 21.11, includes Advanced Transparency, Reflection Dimming, and Wire controls. All shaders include these parameters.

Figure 21.11: The Extended Parameters rollout includes Advanced Transparency, Reflection Dimming, and Wire settings

You can use the Advanced Transparency controls to set the Falloff to be In, Out, or a specified Amount. The In option increases the transparency as you get farther inside the object, and the Out option does the opposite. The Amount value sets the transparency for the inner or outer edge. Figure 21.12 shows two materials that use the Transparency Falloff options on a gray background and on a patterned background. The two materials on the left use the In option, and the two on the right use the Out option. Both are set at Amount values of 100.

The three transparency types are Filter, Subtractive, and Additive. The Filter type multiplies the Filter color with any color surface that appears behind the transparent object. With this option, you can select a Filter color to use. The Subtractive and Additive types subtract from or add to the color behind the transparent object.

The Index of Refraction is a measure of the amount of distortion caused by light passing through a transparent object. Different physical materials have different Index of Refraction values. The amount of distortion also depends on the thickness of the transparent object. The Index of Refraction for water is 1.33 and for glass is 1.5. The default of 1.0 has no effect.

Figure 21.12: Materials with the In and Out Falloff options applied

The Wire section lets you specify a wire size or thickness. Use this setting if the Wire option or the 2-Sided option is enabled in the Shaders Basic Parameters rollout. The size can be measured in either Pixels or Units. Figure 21.13 shows materials with different Wire values from 1 to 5 pixels.

Figure 21.13: Three materials with Wire values of (from left to right) 1, 2, 3, 4, and 5 pixels

Reflection Dimming controls how intense a reflection is. You enable it by using the Apply option. The Dim Level setting controls the intensity of the reflection within a shadow, and the Refl Level sets the intensity for all reflections not in the shadow.

SuperSampling rollout

Pixels are small square dots that collectively make up the entire screen. At the edges of objects where the material color changes from the object to the background, these square pixels can cause jagged edges to appear. These edges are called artifacts and can ruin an image. Anti-aliasing is the process through which these artifacts are removed by softening the transition between colors.

Max includes anti-aliasing filters as part of the rendering process. SuperSampling is an additional anti-aliasing pass that can improve image quality that is applied at the material level. You have several SuperSampling methods from which to choose. The SuperSampling method can be defined in the Material Editor or you can choose the settings in the Default Scanline Renderer rollout of the Render Scene dialog box by enabling the Use Global Settings option.

CROSS-REF 

For more about the various anti-aliasing filters, see Chapter 43, "Learning Rendering Basics."

SuperSampling is calculated only if the Anti-Aliasing option in the Render Scene dialog box is enabled. The raytrace material type has its own SuperSampling pass and doesn't need SuperSampling enabled.

Note 

Using SuperSampling can greatly increase the time it takes to render an image.

In a SuperSampling pass, the colors at different points around the center of a pixel are sampled. These samples are then used to compute the final color of each pixel. These four SuperSampling methods are available:

• Adaptive Halton: Takes semi-random samples along both the pixel's X-axis and Y-axis. It can take from 4 to 40 samples.

• Adaptive Uniform: Takes samples at regular intervals around the pixel's center. It takes from 4 to 26 samples.

• Hammersley: Takes samples at regular intervals along the X-axis but takes random samples along the Y-axis. It takes from 4 to 40 samples.

• Max 2.5 Star: Takes four samples along each axis.

The first three methods enable you to select a Quality setting. This setting specifies the number of samples to be taken. The more samples taken, the higher the resolution, but the longer it takes to render. The two

Adaptive methods (Adaptive Halton and Adaptive Uniform) offer an Adaptive option with a Threshold spinner. This option takes more samples if the change in color is within the Threshold value. The SuperSample Texture option includes maps in the SuperSampling process along with materials.

Maps rollout

A map is a bitmap image that is wrapped about an object. The Maps rollout includes a list of the maps that you can apply to an object. Using this rollout, you can enable or disable maps, specify the intensity of the map in the Amount field, and load maps. Clicking the Map buttons opens the Material/Map Browser where you can select the map type.

CROSS-REF 

Find out more about maps in Chapter 23, "Adding Material Details with Maps."

Dynamic Properties rollout

The properties in the Dynamic Properties rollout, including Bounce Coefficient, Static Friction, and Sliding Friction, are used along with the Dynamics utility in simulations. These properties define how the object is animated during collisions. If these properties are not specified for an object, then the default material settings, which are similar to steel, are used.

Caution 

These dynamic properties are used only with the Dynamic utility, reactor is a more versatile and robust dynamics solution making these properties obsolete; they are included only for backward compatibility.

DirectX Manager rollout

The DirectX Manager rollout lets you display the current material in the viewport as a DirectX shader when the DX Display of Standard Material option is enabled. The current material also can be saved as a .FX material file. Many game engines render using DirectX, so this option lets you view your materials in the viewport as they will appear within the game.

Caution 

The DirectX Manager rollout appears only when the Direct3D display driver is selected.

At the bottom of the DirectX Manager rollout is a drop-down list for selecting to use the available DirectX shaders. The two available DirectX shaders are LightMap and Metal Bump 9. These shaders are generic to be used on a many different types of objects. The Light Map shader includes a parameter for loading a custom light map, and the Metal Bump 9 shader includes parameters for specifying two texture maps; specularity; and normal, bump, and reflection maps.

Mental ray connection rollout

The mental ray connection rollout includes options for enabling different properties that are used by the mental ray rendering engine. The properties include Surface and Shadow Shaders, Photon and Photon Volume, and Extended Shaders and Advanced Shaders, including Contour and Light Map.

CROSS-REF 

The Mental ray rendering engine and its properties are covered in Chapter 45, "Raytracing and mental ray."

Tutorial: Coloring a dolphin

As a quick example of applying materials, we take a dolphin model created by Zygote Media and position it over a watery plane. We then apply custom materials to both objects.

To add materials to a dolphin, follow these steps:

1. Open the  Dolphin.max file from the Chap 21 directory on the DVD. This file contains a simple plane object and a dolphin mesh.

2. Open the Material Editor by choosing Rendering Material Editor, clicking the Material Editor button on the main toolbar, or pressing the M key.

3. In the Material Editor, select the first sample slot; in the Name field (to the right of the Pick Material from Object button), rename the material Dolphin Skin. Click the Diffuse color swatch, and select a light gray color. Then click the Specular color swatch, and select a light yellow color. Click the Close button to exit the Color Selector. In the Specular Highlights section, increase the Specular Level to 45.

4. Drag the Dolphin Skin material from the first sample slot to the second sample slot, and name it Ocean Surface. Click the Diffuse color swatch, and select a light blue color. Set the Specular Level and Opacity values to 80. In the Maps rollout, click the None button to the right of the Bump selection. In the Material/Map Browser that opens, double-click the Noise selection.

5. Drag the Ocean Surface material onto the plane object in the Top viewport. Then drag the Dolphin Skin material onto the dolphin model.

   Note 

   This model also includes separate objects for the eyes, mouth, and tongue. These objects could have different materials applied to them, but they are so small in this image that we won't worry about them.

6. Choose Rendering Environment (keyboard shortcut, 8), click the Background Color swatch, and change it to a light sky blue.

Figure 21.14 shows the resulting image.

Figure 21.14: A dolphin over the water with applied materials