### CAP 202 - Computer Animation II

#### Lesson 14 - Materials

##### Objectives:

This lesson discusses new information about materials. Objectives important to this lesson:

1. Definition of a material
2. Using good materials
3. Materials and lighting
4. Features of the Materials Editor
5. Creating basic materials
6. More materials tools
##### Concepts:

You have used materials several times in these lessons already. It is no surprise that materials may be applied to the objects you make in 3DS Max, giving more realism to your scenes. The text offers a list of benefits to using the right material on an object:

• appropriate look and feel
• desired impression of age (or newness)
• matching the level of realism in your scene

The lesson continues, telling us that we can modify the way a material reacts to light, essentially making a new material. The Material Editor is discussed, introducing features we have not used before.

• The sample slots have been shown to us six at a time (3 x 2) so far. We can also select a 5 x 3 or 6 x 4 view.
• The exercises will use buttons on the vertical and horizontal toolbars.
##### Exercise Notes and Questions

Work through the exercises and turn in your answers to all questions below as part of the homework for this assignment.

Exercise 1: This exercise shows some basic features of the sample slots.
Question 1: What are the three ways listed in the text of opening the Materials Editor?
Question 2: What is the difference between gray triangles and white triangles in the corners of a sample slot?

Exercise 2: Exercise 2 shows us how to change the shape in a sample slot. This may help in applying the sample to an object.
Question 3: What are the three basic shapes that can be selected for a given sample?

Exercise 3: Exercise 3 discusses using a custom shape for a sample slot. The best shape to apply to a sample may be the shape of the object you are applying the material to.

Exercise 4: This exercise begins oddly, saying that we can apply materials with the Material Editor, in addition to creating materials. We will look at creating material in the next exercise.
Question 4: In step 10, what is the trick to dragging a material to an object currently displayed as a wireframe?

Exercise 5: This exercise shows how to create a basic material. It starts by selecting a material slot that has not been used yet.
Question 5: Which Basic Parameter swatch did you use in the exercise to set the basic color of the material?
Question 6: Which parameter controls how large a reflected light (highlight) will appear on the material? Which parameter controls how bright the reflected light will be?

Before beginning the next exercise, the text discusses material types for a few pages The paragraph at the bottom of page tells us that we can assign a new material to a slot that already has a sample in it either by clicking the Get Material button or by clicking the Material Type button. The text gives us an additional fact: if we want to replace a material already assigned to one or more objects, we should use the Material Type button. Using the Get Material button will not update objects that have already been assigned the material we are changing.

The text moves on to discuss eight shader types that can be used to determine the characteristics of a Standard material:

• Anisotropic (uneven) - gives asymmetric reflections and highlights; suggested for brushed metal. Read this discussion of the effect as seen on water, on multiple reflecting surfaces, and on grainy surfaces.
• Blinn - gives a round highlight, good for most materials
• Metal - good for smooth metal material
• Multi-layer - has two anisotropic parameters, to be set differently; recommended for shiny material like silk
• Oren-Nayar-Blinn - a softer version of Blinn, good for cloth and skin
• Phong - supports a shader from older version of the program; similar to Blinn, highlights are not as round
• Strauss - simple shader, not clear when to use it
• Translucent - allows light to pass through it, can simulate self-illumination

In addition to the Standard material, 3DS Max can produce several other material types:

• Raytrace material which produces accurate reflections and refractions of light sources in the scene. This material requires more time to render, can be used for materials that glow.
• Architectural material is useful for scenes in which you can state actual properties of real materials.
• Ink 'n Paint material is useful for scenes that are meant to look more like cartoons or comic books.
• Blend material combines other materials to make a composite.
• Arch & Design material is only available with the Mental Ray renderer. Used for more detailed surfaces, like the Architectural material.

Exercise 6: This exercise puts splashed water on the floor of a scene with a Blend material. It starts with two materials already in sample slots that you combine together.
Question 7: In step 6, why do you use the setting for Keep Old Material as Sub-Material?
Question 8: Read steps 7 and 8 before doing them. In step 8, you are cautioned to drag the second material without selecting it. What would happen if you had selected it?
Step 14 tells you to use the Go To Parent button. It is near the right edge of the horizontal toolbar of the Material Editor.

Exercise 7: This exercise has you save the current scene's materials as a library. This can be useful if you have created custom materials that you intend to use again.