• Surface Dynamics: Shave and a Haircut hair strands are wired and ready for dynamics. Hair guides are created as a dynamic chain and carry their own dynamic properties contained in the normal Maya Attribute Editor. Since hair is best served on a living thing, hair is not dynamically controlled by the overall movement or transform, but rather by skin dynamics. This means that as the skin surface distorts or deforms, so does the hair it is attached to. As skin moves over bone or muscle, the dynamically-driven hair correctly imitates the action. Let's delve into Shave and a Haircut with a quick and easy example.

[Figures 1, 2, 3] The polygon bird model ready for hair (left). Shave and a Haircut's two menus are nestled among the Maya menus (top right). Two views of selected polygons shaded dark (bottom right). These polygons produce hair. 

A Furry Bird
It is very easy to get hair to grow on something quickly. Load the scene file bird_1.mb into Maya. It is located on the companion DVD in the Chapter 3 folder. A quick render should reveal our polygon model with lighting, as shown in Figure 1.

This particular model is made of polygons, but Shave and a Haircut grows hair on just about any object type. When the plugin is loaded, Shave and a Haircut places two menus within the menus in the Maya menu bar, and they remain constant throughout all Maya menu sets. These two menu selections are shown in Figure 2.

There are many ways to direct Shave and a Haircut to place hair. This time we will select specific polygons on the model that will grow hair. It may help to make the box room invisible in the Channel Editor. This may make it slightly easier to select the specific polygons. It may also be easier to select all the polygons of the head and then deselect the face polygons that should be hairless. Figure 3 shows two alternate views of the bird's body, with polygons deselected.