Interpolation Rollout (Sweep Modifier)

The controls on the Interpolation rollout of the Sweep modifier work exactly as they do for any other spline. However, the controls affect only the built-in section you've chosen, not the spline that the section is swept along.

Modify panel > Select a 2D shape. > Modifier List > Sweep > Interpolation rollout
Default menu: Select a 2D shape. > Modifiers menu > Patch/Spline Editing > Sweep > Modify panel > Interpolation rollout
Alt menu: Select a 2D shape. > Modifiers menu > Spline > Sweep > Modify panel > Interpolation rollout

Note: If you want to change the interpolation settings of the underlying spline path, you need to select the path object in the modifier stack.

In general, all spline curves are divided into small straight lines that approximate a true curve. The number of divisions between each vertex on the spline are called steps. The more steps used, the smoother the curve appears.

Note: The Interpolation rollout is active only when built-in sections are used.

Steps

Sets the number of divisions, or steps, 3ds Max uses between each built-in section's vertices. Splines with tight curves require many steps to look smooth while gentle curves require fewer steps. Range=0 to 100.

Left: The quarter-round section is set to zero steps.

Right: The same section on the right is set to four steps.

Spline steps can be either adaptive or manually specified. The method used is set by the state of the Adaptive switch. The main use for manual interpolation is to create splines for morphing or other operations where you must have exact control over the number of vertices created.

Optimize

When on, removes unneeded steps from straight segments in the spline. Default=on.

Note: Optimize is not available when Adaptive is on.

Left: Optimize is on for the left-hand sweep. Right: Optimize is off for the right-hand sweep.

Adaptive

When on, automatically sets the number of steps for each spline to produce a smooth curve. Straight segments always receive 0 steps. When off, enables manual interpolation control using Optimize and Steps. Default=off.