Transform one CV and have surrounding CVs follow it

Move (in space, or relative to the geometry), scale, or rotate multiple CVs at once, with the amount of transformation relative to the CVs distance from the primary CV you click.

Use the Proportional Mod tool from the Control Panel

Choose Control Panel > Transform CV .
From the Transform menu, choose Prop mod.
Choose a mode from the Mode menu.

See Mode for a description of the different modes.
Select the primary CV. All other CVs will move with respect to this CV.
NoteIf the CVs are not visible, click on the object and they will be displayed automatically.

A green jack locator apears on the CV, and eight blue arrows appear around it.
Select the range of CVs that you want to transform, by doing one of the following:
- Click on the blue arrows to select/deselect rows of CVs.
- Hold down the key, and click on a CV (or box-select) to select/deselect additional rows. (See Specify the selection range below for more details.)
A numeric label shows how many rows of CVs have been selected in each direction. Selecting and deselecting CVs always maintains a "rectangular" selection.
In the Falloff window, adjust the falloff values in the U and V direction. By default the sliders are synchronized. To decouple them, click the chain link icon. (See Adjust the falloff values below for more details.)
Drag to transform the CVs. The mouse buttons operate in the same way as for the Move transformation.

Set Transform to Pivot if you need to move the pivot before rotating or scaling CVs. The options from Transform > Local > Set Pivot are used to determine which pivot(s) to move (Rotation, Scaling, or both).
Modify the falloff values, mode, range of CVs, or even the primary CV itself. The other parameters are maintained. You can even change the Transform option and come back to Prop Mod without losing your settings.
NoteAll with all other Transform CV applications, Mouse Sensitivity and Step Size can be used with this Prop Mod tool.

Specify the selection range

You must first select the primary CV by clicking on it. The primary CV defines the point from which falloff is calculated and applied to the range of CVs. It is indicated by a green jack locator.

If only one CV is selected when the Prop Mod tool is invoked, it becomes the primary CV.

Note

If the CVs are not visible on the object, clicking it first will turn on the hull and CVs.

Small blue arrows appear around the primary CV, allowing you to select/deselect additional rows of CVs to define the range that will be affected by Prop Mod.

Click an outward pointing arrow to add CVs to the range in the given direction.
Click an inward pointing arrow to remove CVs from the range in the given direction.

If you keep the mouse button depressed, rows of CVs are continuously added/removed to/from the selection. if you click and release, rows are added/removed one at a time.

A numeric label shows how many rows of CVs have been selected for each direction.

Selecting and de-selecting CVs always maintains a “rectangular” selection.

Instead of using the blue arrows, you can also select the range of CVs by holding down the key, and:

Box selecting the entire range.
Selecting the CVs at the extent of the range. The intermediate CVs are added to the range.
Selecting already selected CVs to de-select them along with all CVs on the same hull lines and those further away.

NoteThe CV selection is retained when changing modes within the Prop Mod tool. However, changing tools deselects all the CVs.

Adjust the falloff values

As with the Transform > Modify > Proportional tool, we use a range-based modification. That is, the greater the number of CVs between the primary CV and the boundary of the defined region, the less effect the transformation has on each CV.

The falloff window appears as soon as the Prop Mod tool is selected.

By default the U and V falloff sliders move in sync. To decouple them, click the chain link icon on the right hand side of the window. A value of 0.0 means that all CVs move by the same amount. A value of 1.0 (default) corresponds to a linear falloff. The higher the falloff value, the less effect the movement of the primary CV has on the surrounding CVs.

The slider settings are maintained between applications of the tool.

Apply Prop Mod across multiple surfaces

Under certain conditions, it is possible to select CVs on surfaces adjacent to the surface containing the primary CV and apply the modification across several surfaces.

The surfaces must share an edge (that is, have positional continuity).
The surfaces must have the same number of CV rows in the same locations.
The surfaces must line up in the direction across which you are selecting CVs, as shown in Figure A below.
The surfaces must form a rectangular grid if you want to expand the selection to adjacent surfaces in both directions, as shown in Figure B below.

Figure A: Four adjacent surfaces.

Figure B: Six adjacent surfaces forming a rectangular grid.

NoteYou can also use the Hot Spot Interface to switch between options in order to reduce mouse movement across the screen. To see this interface, hold down the space bar while in the Transform CV tool.

Alternate method: Use the Proportional Mod tool from the Palette (deprecated)

NoteThis tool is deprecated and will be removed in a future release. We recommend that you use the Transform CV workflow described above.

Show CVs on the picked objects

Click the Cv/Hull checkbox in the Display section of the Modeling control panel

or do the following:

Choose ObjectDisplay > Control ❒.
Set Scope to Active and turn on the CVs checkbox.
Click Go.

Transform CVs proportionally in relation to a primary CV

Choose Transform > Modify > Proportional Mod ❒.
Click the CV to use as the primary CV.
Use the option box to set the following:
- The Operation to perform on the CVs.
- The number of CVs before (Preceding U and V) and after (Preceding U and V) the primary CV that will follow along.
- The Move Mode: choose XYZ to move the CVs in world space, or NUV to move the CVs relative to the surface (in the normal, U, and V).
Use the mouse or keyboard to move, scale, rotate, or smooth the primary CV.
The affected CVs (the number of CVs before and after the primary CV as specified in the option box) follow along, with the amount of transformation relative to their distance from the primary CV.