INSIDE 3DS MAX® 7 [Electronic resources] نسخه متنی

The Material Editor

Materials, which you create and modify through the Materials Editor, control how light interacts with an object's surface. Since this chapter assumes that you've already gone through all the basic 3ds max 7 tutorials included with the program and are familiar with most 3ds max features, I'll provide only a brief overview of the Material Editor.

The Material Editor for 3ds max 7 (Figure 10.1) hasn't changed substantially since the release of 3D Studio MAX R1 back in the spring of 1996. This isn't necessarily a criticism, because the original design of the Material Editor was extremely advanced for its time and gave users the ability to create complex layered textures with relative ease. In short, it's aged pretty well, although there's always room for improvement.

This figure shows the default settings of the Material Editor when you first open it, using the Material Editor icon on the Main toolbar. An array of buttons on the right side of the menu enables you to change the material sample sphere display optionssample type (sphere, cylinder, and box), the lighting on the sample objects (backlight on or off), the background display of the sample objects (useful when working with translucent materials), and so on.

Double-clicking a sample sphere window opens a larger, floating version of the sample for closer inspection of the texture. Right-clicking the sample sphere area also brings up a menu where you can display more texture sample windows3 by 2, 5 by 3, or 6 by 4.

Although the maximum number of material samples you can show in the Material Editor at one time is 24, remember that you're not limited to only 24 materials in your scene! Create new materials in the Material Editor (and apply them in your scene) by clicking any sample sphere, clicking the Material Editor X icon (which resets your Map/Material to the default settings), and then checking "Affect only mtl/map in the editor slot." This clears the material slot. Name this new material whatever you like and alter its parameters and maps as needed.

Resetting your Map/Material to the default settings enables you to create new materials for your scene, even if all your Material Editor slots are currently filled. Figure 10.2 shows the Map Reset dialog.

Shader Types

The first materials component item we'll look at in the Material Editor is the shader type. (A shader determines global aspects of how a surface will render.) The initial shader type forms the backbone of all Standard materials you create in 3ds max 7.

At the top of the Material Editor is the Shader Basic Parameters rollout, which contains a drop-down list of different shader types. The default shader is Blinn (named after James Blinn, one of the pioneers of computer graphics rendering). Blinn works well in many situations, but if you click the drop-down list you can choose from other shader types, including these:

• Anisotropic
  Creates custom specular highlights for metals, hair, velvet cloth, and other glossy, textured materials where the angle of incident light affects the brightness and color of the object.

• Metal
  For metallic finishes.

• Multi-Layer
  For complex materials with different shading components.

• Oren-Nayar-Blinn
  Ideal for rough or matte surfaces such as a chalkboard.

• Phong
  Provides shinier highlights than Blinn.

• Strauss
  Similar to the Metal shader, but with only one color component and no separate specular component.

• Translucent Shader
  Simulates translucent, "two-sided" materials. This shader, new to 3ds max 7, can help you create thin, translucent materials such as paper or frosted glass. It is not, however, a true subsurface scattering (SSS) shader that can accurately simulate materials such as marble, wax, and skin that allow a percentage of light to penetrate their surfaces.

Many third-party plug-in shaders are available for free download or purchase to supplement the core 3ds max 7 shader options.

Material Types

The second major component of 3ds max 7 Materials is the actual material type. The default material type is Standard. Clicking the Material Type button brings up the Material/Map Browser (Figure 10.3), which lets you pick additional types.

The core 3ds max materials (that is, materials not specific to mental ray) are these:

• Advanced Lighting Override
  Used in conjunction with the 3ds max 7 Light Tracer and Radiosity features.

• Architectural
  Provides features taken from the Autodesk VIZ program, an engineering/architectural offshoot of the base 3ds max program.

• Blend
  Blends and combines multiple material types.

• Composite
  Layers complex materials and maps.

• Double Sided
  Creates two-sided materials, with one material showing on the front of your model's face normals while a different material shows on its back-face normals.

• Ink 'n Paint
  A basic cartoon and cel-look shader.

• Lightscape Mtl
  The Lightscape material enables you to set radiosity parameters for meshes that you want to export to Lightscape. Lightscape (now a discontinued product) is an Autodesk 3D rendering package, used primarily for architectural visualization where extremely high-quality radiosity rendering is required.

• Matte/Shadow
  For special effects and compositing purposes when you need an object to reveal whatever environment background you've loaded.

• Morpher
  Used to transition between morphing object types and their materials.

• Multi/Sub-Object
  Allows you to more carefully organize and place specific materials on selected faces of your geometry using assigned Material ID numbers. We'll cover this material in detail later in this chapter.

• Raytrace
  Provides a host of reflection and refraction options, offers greater Specular control than a Standard material, and includes Diffusion mapping (lacking in other 3ds max 7 materials). There's also a Raytrace map type, described below, which you can use in the map slot of any regular 3ds max 7 material.

• Shell Material
  Works in conjunction with the Render To Texture feature to bake a complex texture hierarchy (consisting perhaps of multiple procedural texture layers) down to a single bitmap that can be saved to disk. This material can save on rendering time.

• Shellac
  Another composite material that creates glossy surfaces.

• Top/Bottom
  Blends different materials based on object coordinates or world coordinates or both. Top/Bottom is useful for varying textures according to the "height" of a surfacefor example, creating snow on mountaintops, dust on the tops of objects, and so on.

Now that you've seen the basic shader and material types, let's take a look at 3ds max 7's huge variety of map types.

Map Types and Examples

There are two main map types in 3ds max 7 (and pretty much every other 3D program): bitmaps and procedural maps.

Bitmaps consist of single still images in typical image file formats such as .jpg, .tif, .tga, and .bmp, or image sequences applied to create animated surface effects. They can be created from scratch using a paint program such as Adobe Photoshop or Corel Painter, imported from scanned print or digital photos, digitized from video, created as a rendering from an existing 3D scene, or crafted using a combination of any of these techniques.

For the most photorealistic results, it's better to use as many real-world textures in your scene as possible. For example, if you're depicting a wooden tabletop with scratches, dings, and dents, an actual photo of a wooden tabletop (along with a separate Bump map for the surface imperfections) will invariably look better than a map you've painted from scratch (unless you're an absolutely amazing 2D artist). The inherent flaws and idiosyncrasies of real-world images are tough to duplicate in digital artwork, so going back to nature is the obvious solution. Examples of such textures are shown in Figure 10.4.

Procedural maps are purely mathematical creationsalgorithms that generate surface effects. They range from standard, bread-and-butter Noise functions that "rough up" any surface to custom effects such as electricity, water surfaces, fantasy patterns, and so on. You can often use combinations of procedural and bitmap textures to produce more varied effects in your scene. One thing to remember: Bitmaps are 2D in nature and can be thought of as paint on the surface of your 3D objects, while procedurals are 3D in nature and "permeate" the entirety of your object. Keep this essential difference in mind as you plan future experiments in texturing.

Max's Map Types

Here is the list of 3ds max 7 standard map types (Figure 10.5):

• Bitmap
  For still images or image sequences.

• Camera Map Per Pixel
  Enables you to render and save high-resolution images of 3D scenes, retouch them (if necessary), then reapply those images as Camera Projection maps onto the original geometry. This is most useful for creating high-resolution matte paintings for the backgrounds and virtual sets of visual effects shots.

• Cellular
  Complex map useful for organic patterns such as skin cells, as well as water surfaces, electrical arcs, and other effects.

• Checker
  Creates checkerboard patterns; squares can be customized according to number of squares, color, width, and height.

• Combustion
  Provides a link to combustion, discreet's paint and compositing program. Use combustion to paint on the surface of a max object and see the results in the viewports.

• Composite
  Helpful for layering additional maps.

• Dent
  Most useful in the Bump map slot.

• Falloff
  An extremely versatile map for iridescent and reflection effects (as you'll see in the next chapter).

• Flat Mirror
  Makes flat reflective surfaces.

• Gradient
  Creates either linear or radial gradients; especially useful for masking.

• Gradient Ramp
  Similar to Gradient, but with more color and mapping controls.

• Marble
  Imitates the veining and coloration of marble.

• Mask
  A map put in the Mask slot will mask underlying maps.

• Mix
  Used to blend two or more maps.

• Noise
  A workhorse procedural texture that you can use throughout your 3D scenes.

• Normal Bump
  Creates material Bump maps using color channel information.

• Output
  For boosting the output of a submap that lacks the standard Output Parameter controls.

• Particle Age
  Helps control particle color and opacity.

• Particle Mblur
  Helps adjust particle motion blur.

• Perlin Marble
  A modified Marble texture offering additional controls.

• Planet
  A generic planet surface map.

• Raytrace
  Most often used in the Reflection and Refraction slots of a Standard material to generate realistic mirror and glass surfaces.

• Reflect/Refract
  Applies environmental reflections in your 3D scene; usually faster than a Raytrace map.

• RGB Multiply
  Useful when you want to use a map to boost or suppress the RGB values of a submap.

• RGB Tint
  Similar to RGB Multiply; used to color-correct an existing submap.

• Smoke
  A softer Noise function.

• Speckle
  Produces random speckles and blobs.

• Splat
  Similar to Speckle, but with larger, spikier blobs.

• Stucco
  A pattern most useful for Bump mapping.

• Swirl
  Produces soft, swirled color transitions.

• Thin Wall Refraction
  Used to suggest the refraction of glass panes when you don't want to use a Raytrace map.

• Tiles
  Produces geometric tesselated patterns; replaces the Brick map in earlier versions of 3ds max.

• Vertex Color
  Creates special color effects; used for model shading in game engines.

• Waves
  Produces convincing water surface effects.

• Wood
  A simple procedural wood shader.

In the next chapter, you'll learn how to make your own custom textures using a combination of bitmaps and procedural textures. We'll also discuss modifying and improving existing bitmap textures for 3D rendering.

Dancing About Architecture

There's a saying that "writing about music is like dancing about architecture." The same could be said about text descriptions of colorful CG texturesthey're uninformative at best, misleading at worst. It's much better to see the images up close and personal so you can figure out what they do. Without further ado, let's look at all the shader, material, and map types, all at once.

This file, by 3D artist Peter Clay of discreet's Quality Engineering (software testing) department, includes samples of every shader, material, and map type that is not specific to mental ray. Each type is clearly labeled and accompanied by its own appropriately mapped Sphere object. If you go to the Command panel > Display tab and uncheck the Cameras box, you'll also see that there is a close-up camera for each sample sphere, as well as a moving camera that pans past every sphere during the course of 100 frames. If you're unfamiliar with what any shader, material, or map does in 3ds max 7, use this scene as a quick reference.