3ds Max 2012 Bible - Kelly L. Murdock [146]
Working in 2D in Max, you use two general objects: splines and shapes. A spline is a special type of line that curves according to mathematical principles. In Max, splines are used to create all sorts of shapes such as circles, ellipses, and rectangles.
You can create splines and shapes using the Create⇒Shapes menu, which opens the Shapes category on the Create panel. Just as with the other categories, several spline-based shape primitives are available. Spline shapes can be rendered, but they are normally used to create more advanced 3D geometric objects by extruding or lathing the spline. You can even find a whole group of modifiers that apply to splines. You can use splines to create animation paths as well as Loft and NURBS (Non-Uniform Rational B-Splines) objects, and you will find that splines and shapes, although they are only 2D, are used frequently in Max.
Drawing in 2D
Shapes in Max are unique from other objects because they are drawn in 2D, which confines them to a single plane. That plane is defined by the viewport used to create the shape. For example, drawing a shape in the Top view constrains the shape to the XY plane, whereas drawing the shape in the Front view constrains it to the ZX plane. Even shapes drawn in the Perspective view are constrained to a plane such as the Home Grid.
You usually produce 2D shapes in a drawing package such as Adobe Illustrator (AI) or CorelDRAW. Max supports importing line drawings using the AI format.
Cross-Reference
See Chapter 3, “Working with Files, Importing, and Exporting,” to learn about importing AI files. •
Whereas newly created or imported shapes are 2D and are confined to a single plane, splines can exist in 3D space. The Helix spline, for example, exists in 3D, having height as well as width values. Animation paths in particular typically move into 3D space.
Working with shape primitives
The shape primitive buttons are displayed in the Object Type rollout of the Create panel when either the Create⇒Shapes or the Create⇒Extended Shapes menu is selected. The Shapes category include many basic shapes, including Line, Circle, Arc, NGon (a polygon where you can set the number of sides), Text, Section, Rectangle, Ellipse, Donut, Star, and Helix, as shown in Figure 12.1. The Extended Shapes category includes several shapes that are useful to architects, including WRectangle, Channel, Angle, Tee, and Wide Flange, as shown in Figure 12.2. Clicking any of these shape buttons lets you create the shape by dragging in one of the viewports. After a shape is created, several new rollouts appear.
FIGURE 12.1
The shape primitives in all their 2D glory: Line, Circle, Arc, NGon, Text, Section, Rectangle, Ellipse, Donut, Star, and Helix
Above the Shape buttons are two check boxes: AutoGrid and Start New Shape. AutoGrid creates a temporary grid, which you can use to align the shape with the surface of the nearest object under the mouse at the time of creation. This feature is helpful for starting a new spline on the surface of an object.
FIGURE 12.2
The extended shape primitives: WRectangle, Channel, Angle, Tee, and Wide Flange
Cross-Reference
For more details on AutoGrid, see Chapter 7, “Transforming Objects, Pivoting, Aligning, and Snapping.” •
The Start New Shape option creates a new object with every new shape drawn in a viewport. Leaving this option unchecked lets you create compound shapes, which consist of several shapes used to create one object. Because compound shapes consist of several shapes, the shapes are automatically converted to be an Editable Spline