3ds Max 2012 Bible - Kelly L. Murdock [320]
FIGURE 27.16
The Loft compound object rollouts
The viewport displays a small yellow X at the location where the new cross-sectional shape will be inserted. At the bottom of the rollout are three buttons, which are illustrated and described in Table 27.1.
Setting skin parameters
The Skin Parameters rollout includes many options for determining the complexity of the Loft skin. You can specify whether to cap either end of the Loft using the Cap Start and/or Cap End options. The caps can be either Morph or Grid type.
This rollout also includes the following options for controlling the look of the skin:
• Shape and Path Steps: Sets the number of segments that appear in each spline's cross-sectional shape and between each division along the path. The straight segments are ignored if the Optimize Path option is selected.
• Optimize Shapes and Paths: Reduces the Loft's complexity by deleting any unneeded edges or vertices.
• Adaptive Path Steps: Automatically determines the number of steps to use for the path in order to maintain a smooth curve.
• Contour: Determines how the cross-sectional shapes line up with the path. If this option is enabled, the cross section is aligned to be perpendicular to the path at all times. If disabled, this option causes the cross-sectional shapes to maintain their orientation as the path is traversed.
• Banking: Causes the cross-section shape to rotate as the path bends.
• Constant Cross-Section: Scales the cross-sectional shapes in order to maintain a uniform width along the path. Turning off this option causes the cross sections to pinch at any sharp angles along the path.
• Linear Interpolation: Causes straight linear edges to appear between different cross-sectional shapes. Turning off this option causes smooth curves to connect various shapes.
• Flip Normals: Used to correct difficulties that would appear with the normals. Often the normals are flipped accidentally when the Loft is created.
• Quad Sides: Creates four-sided polygons to connect to adjacent cross-section shapes with the same number of sides.
• Transform Degrade: Makes the Loft skin disappear when subobjects are transformed. This feature can help you better visualize the cross-sectional area while it is being moved.
The Display options at the bottom of the Skin Parameters rollout give you the choice of displaying the skin in all viewports or displaying the Loft skin only in the viewports with shading turned on.
Tutorial: Designing a slip-proof hanger
As an example of creating a Loft object with different cross-sectional shapes, you'll design a new hanger that includes some rough edges along its bottom section to keep slacks from sliding off.
To design a hanger Loft object with different cross sections, follow these steps:
1. Open the Lofted slip-proof hanger.max file from the Chap 27 directory on the CD.
This file includes a spline outline of a hanger and two simple shapes.
2. Select the hanger spline, and choose the Create⇒Compound⇒Loft menu command.
3. In the Creation Method rollout, click the Get Shape button and then click the small circle shape (make sure that the Copy option is selected).
This lofts the entire hanger with a circular cross section.
4. In the Path Parameters rollout, select the Path Steps option. A dialog box appears warning that this may change the relocate shapes. Click Yes to continue. Increment the Path value until the yellow X marker in the viewport is positioned at the beginning of the hanger's bottom bar (at Step 53 for this tutorial). Click the Get Shape button again, and click the small circular shape again.
This extends the circular cross section from the start at Step 0 to Step 53.
5. Increment the Path value by 1 to Step 54, click the Get Shape button, and select the star shape. This makes the remainder of the hanger use a star-shaped cross section. Increment the Path value again to the end of the hanger's bottom bar (at Step 60), click the Get Shape button, and select the star shape again to end the star cross section.
Note