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

3.In the Material Editor, select the first sample slot; in the Name field, name the material Curtains. Select the Translucent Shader from the Shader Basic Parameters rollout. Click the Diffuse color swatch, and select a light blue color. Click the Close button to exit the Color Selector.

4.Click the Translucent Color swatch, change its color to a light gray, and set the Opacity to 75.

5.Drag the Curtains material onto the curtain object in the Left viewport.

Figure 20-10 shows the resulting image. Notice that the tree’s shadow is being cast on the curtains.

Figure 20-10: These translucent window curtains show shadows.

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

In addition to the Basic Parameters, the Material Editor includes several more settings that are common for most shaders. The Extended Parameters rollout, shown in Figure 20-11, includes Advanced Transparency, Reflection Dimming, and Wire controls. All shaders include these parameters.

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Figure 20-11: 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 20-12 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.

Figure 20-12: Materials with the In and Out Falloff options applied

The three transparency types are Filter, Subtractive, and Additive. The Filter type multiples 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.

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The Wire section lets you specify a wire size or thickness. Use this setting if the Wire mode is enabled in the Shaders rollout. The size can be measured in either Pixels or Units. Figure 20-13 shows materials with different Wire values from 1 to 5 pixels.

Figure 20-13: 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.

Cross-	For more about the various anti-aliasing filters, see Chapter 41, “Rendering Basics.”
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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.

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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 pasted on an image. 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-	Find out more about maps in Chapter 22, “Adding Material Details with Maps.”
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Dynamic Properties rollout

The properties in the Dynamic Properties rollout 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.

The Dynamic Properties rollout includes only the following three values:

Cross-

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Bounce Coefficient: Determines how high an object bounces after a collision. The default of 1.0 is equal to a normal elastic collision. A ball with a value greater than 1, for example, continues to bounce higher with each impact.

Static Friction: Determines how difficult it is to start an object moving when pushed across a surface. Objects with high Static Friction values require lots of force to move.

Sliding Friction: Determines how difficult it is to keep an object in motion across a surface. Ice, for example, has a low Sliding Friction value, because after it starts moving, it continues easily.

For more information on dynamic simulations, check out Chapter 39, “Creating a Dynamic Simulation.”

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.

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Cross-	The mental ray rendering engine and its properties are covered in Chapter 44, “Raytracing
Reference	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 20 directory on the CD-ROM. 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, doubleclick 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 20-14 shows the resulting image.