3ds Max 2012 Bible - Kelly L. Murdock [304]
Even if the entire mesh is deleted using the Delete Mesh modifier, the object still remains. To completely delete an object, use the Delete key. •
Extrude modifier
The Extrude modifier can be applied only to spline or shape objects, but the resulting extrusion can be a Patch, Mesh, or NURBS object. This modifier copies the spline, moves it a given distance, and connects the two splines to form a 3D shape. Parameters for this modifier include an Amount value, which is the distance to extrude, and the number of segments to use to define the height. The Capping options let you select a Start Cap and/or an End Cap using either a Morph or Grid option. The Morph option divides the caps into long, thin polygons suitable for morph targets, and the Grid option divides the caps into a tight grid of polygons suitable for deformation operations. The Cap fills the spline area and can be made as a Patch, Mesh, or NURBS object. Only closed splines that are extruded can be capped. You can also have mapping coordinates and Material IDs generated automatically. The Smooth option smoothes the extrusion.
Cross-Reference
Chapter 12, “Drawing and Editing 2D Splines and Shapes,” includes a good example of the Extrude modifier. •
Face Extrude modifier
The Face Extrude modifier extrudes the selected faces in the same direction as their normals. Face Extrude parameters include Amount and Scale values and an option to Extrude From Center. Figure 26.7 shows a mesh object with several extruded faces. The Mesh Select modifier was used to select the faces, and the extrude Amount was set to 30.
FIGURE 26.7
Extruded faces are moved in the direction of the face normal.
Tutorial: Extruding a bullet
As a simple example that uses a couple of Mesh modifiers, you'll create a single bullet using a hemisphere object. You can create this simple object in other ways, but this offers some good practice.
To create a bullet using the Face Extrude modifier, follow these steps:
1. Select Create⇒Standard Primitives⇒Sphere, and drag in the Top viewport to create a sphere object. Set the Radius value to 60 and the Hemisphere value to 0.5 to create half a sphere.
2. Right-click on the sphere object, and select Convert To⇒Editable Poly in the pop-up quadmenu to convert the hemisphere to an Editable Poly object.
3. Select the Top viewport, right-click on the viewport name, and select Views⇒Bottom from the pop-up menu (or press the B key) to switch to the Bottom view.
4. In the Selection rollout, click the Vertex button to enter Vertex subobject mode and enable the Ignore Backfacing option. Then select the single vertex in the center of the hemisphere, and press the Delete key.
5. In the Selection rollout, click the Border button to enter Border subobject mode, and then click the edge of the hemisphere in the Front viewport to select the border of the hole that was created by deleting the center vertex. Then click the Cap button in the Edit Borders rollout.
6. Select the Polygon button in the Selection rollout to enter Polygon subobject mode and select the bottom polygon subobject in the Perspective viewport after rotating the object around. Then select Modifiers⇒Mesh Editing⇒Face Extrude to apply the Face Extrude modifier to the selected polygon face. Set the Amount value to 200.
7. Select Create⇒Standard Primitives⇒Cylinder, and drag in the Bottom viewport to create a thin Cylinder object that is just wider than the extruded hemisphere. Then move the new Cylinder object until it is positioned at the end of the bullet object.
Figure 26.8 shows the completed simple bullet.
FIGURE 26.8
A simple bullet can be created by extruding one face of a hemisphere.
ProOptimizer modifier
Although the latest game consoles are getting much better at handling lots of polygons, sometimes you'll want to reduce a high-resolution model. For example, if you have a high-res statue in your scene, you might want the same statue to be lower-res when used as part of the background. Max offers an excellent modifier that enables you to reduce the total