Man-made materials are far easier to work with in both creation and animation.
Why? Well, if you look around you, you are surrounded with all kinds of ideas for materials in your scene.
Some materials are animated; some are not.
Whatever the case, you will find that almost every material that occurs as a result of human intervention is re-creatable within your 3D application.
Although you can use any of the maps discussed earlier in this chapter to create man-made materials, some other specific maps can assist you in creating more realistic materials.
Maps to use with man-made materials: When designing a man-made material within your 3D application, you can use several different kinds of maps.
You typically need to be more precise with man-made materials, however, because they are often based on exacting figures.
For instance, a steel plate that has bolts around the edges could be easily recreated using a Procedural map like Bitmap in the Diffuse channel.
In any case, you will find that there are certain maps that work well for faithfully reproducing real-world materials in your 3D application.
The first, and perhaps most used, is the Bitmap.
Bitmap essentially allows you to use an image, in one of several supported image file types, as a color or rendering property of a material.
Images can include anything from scans of real objects or images to animations from your 3D application or other programs.
As with many other maps, you can animate Bitmap's values of Offset, Tiling, and Angle.
In many cases, animating the offset of a bitmap-especially for decals-is more practical than for Procedural maps.
New to your 3D application is the capability to crop a bitmap or place it anywhere within a material by scaling it down.
The Crop and Place controls eliminate the need for a paint program for cropping and scaling, the only functions many people used them for.
Another benefit of using your 3D application's cropping is that it can be animated.
Animating the cropping rectangle moves the stripes as if the pole were spinning.
The Place feature works by using the entire bitmap.
The window, rather than acting as a cropping window, allows you to scale and place the entire map on the surface of an object.
Another benefit of using the Bitmap map type for man-made materials is that you can use animation files, such as AVI or sequential still frames.
This means that you can use both computer-generated animations and also high resolution captured video as a texture for a material.