Editing Point Sub-Objects

This topic describes the controls for point sub-objects. A rollout labeled Point contains the point sub-object controls for NURBS models. In addition to the Point rollout described here, the Point sub-object level displays the Soft Selection rollout.

• Modify panel > Select a NURBS object or sub-object. > Point sub-object level > Select point sub-objects.
• Modify panel > Select a NURBS object or sub-object. > Right-click. > Tools 1 (upper-left) quadrant > Sub-objects > Point > Select point sub-objects.

Procedures

To transform point sub-objects:

1. At the Point sub-object level, select one or more points.

   The sub-object selection tools are the same as for other kinds of sub-objects. You can also use the H key while the Keyboard Shortcut Override toggle is on. See Sub-Object Selection.

   The Selection group box, described under "Interface" later in this topic, provides some additional options for selecting Point sub-objects.

2. Activate (Select And Move) or another transform and then drag in a viewport to transform the selection.

   The shape of the model changes as you interactively transform the points.

   Rotate and Scale are useful only when you've selected multiple points.

Tips

• The Lock Selection Set button is useful when you transform NURBS point sub-objects. You can make a selection in one viewport, click Lock Selection Set (or press Ctrl+Shift+N), and then transform the selection in a different viewport.
• When you move point sub-objects, move them as systematically as possible to avoid "getting lost."
• On surfaces, avoid moving points so they cross over or under adjacent points. This can create odd-looking warps or overlaps in the surface.

To Shift+Clone a point sub-object:

• Hold down Shift while you transform the point.

  This works only for points that lie on curves or surfaces, independent point sub-objects, and curve point or surface point sub-objects that lie on the curve or surface (that is, that aren't displaced).

To use the keyboard to select point sub-objects:

You can select point sub-objects using the Ctrl key and the arrow keys. The arrows traverse the sub-objects in the order they were created. To do so, follow these steps:

1. Turn on (Keyboard Shortcut Override Toggle).
2. Click or drag to select points.
3. Hold down Ctrl and use the arrow keys to move among the point sub-objects.

   For points on curves, the arrow keys traverse the point selection along the length of the curve. The arrow keys don’t move between curve sub-objects.

   For points on surfaces, the left-arrow and right-arrow keys traverse the U dimension of a surface, while the up-arrow and down-arrow keys traverse the V dimension of the surface. The arrow keys don’t move between surface sub-objects.

   The arrow keys don’t traverse individually created points that aren’t part of a curve or surface.

You can also use the H keyboard shortcut (while the Keyboard Shortcut Override Toggle is on) to display a dialog and select points by name. Ctrl+H displays only the names of points directly beneath the mouse cursor.

To remove a point from a curve:

1. Select a point.
2. In the Delete group box, click Point.

   Keyboard shortcut: Delete

   The point is deleted and the shape of the curve is updated.

   Note: An open point curve must have at least two endpoints.

To remove points from a surface:

1. Select a point, row, or column.

   The appropriate Delete buttons are enabled.

2. In the Delete group box, click Point, Row, or Col.

   The point, row, or column is deleted. Deleting a "single" point actually deletes both the row and column to which the point belongs.

To add a point to a curve:

1. In the Refine group box, turn on Curve.
2. Click the curve where you want to add the point.

   A point is added at the location you clicked. The curvature can change.

To add a point and extend the length of a curve:

1. Click to turn on Extend.
2. Move the mouse over a point curve. The curve is highlighted in blue, and one of the curve's ends displays a box to show where the curve will be extended.
3. Drag from the highlighted end point, and then release the mouse button.

   A new point is added beyond the original length of the curve.

To add points to a point surface:

1. In the Refine group box, click Surf Row, Surf Col., or Surf Row & Col.
2. Click the surface.

   A row, a column, or both are added close to the point where you clicked the surface. The new points are placed on the surface so they preserve the surface’s curvature. The curvature can change, but only slightly.

To fuse two points:

1. Turn on Fuse.
2. Click a point without releasing the mouse button. Drag to another point, and then release the mouse button.

   The first point you choose acquires the position of the second point, and becomes dependent to it. If the first point has an animation controller, the controller is discarded. If the second point has an animation controller, the first point acquires it too.

   Fused points display in purple by default.

To unfuse fused points:

1. Select the fused point.
2. Click Unfuse.

   Now you can move and edit the two points independently.

To transform a region:

1. Using sub-object selection, select one or more points for the center of transformation.
2. Turn on Soft Selection.
3. Transform the point.

   A region around the selected point is transformed accordingly.

Move is the most common transform to use. Rotate and Scale can be used with a non-local transform center.

Tip: If Soft Selection appears not to be working, the Falloff value might be too small for the size of your surface. On the Soft Selection rollout, increase the value of Falloff so it encompasses other points.

Interface

In addition to the Point rollout described here, the Point sub-object level also displays the Soft Selection rollout.

Selection group

Point sub-object selection controls

Single Point

(The default.) When on, you can select individual points by clicking, or groups of points by dragging a region.

Row of Points

When on, clicking a point selects the entire row the point belongs to. Dragging selects all rows in the region.

If the point is on a curve, Row of Points selects all points in the curve.

Column of Points

When on, clicking a point selects the entire column the point belongs to. Dragging selects all columns in the region.

If the point is on a curve, Column of Points selects only a single point.

Row and Column of Points

When on, clicking a point selects both the row and column the point belongs to. Dragging selects all rows and columns in the region.

All Points

When on, clicking or dragging selects all the points in the curve or surface.

Tip: Rows and columns are easily visible when the NURBS surface is planar, or nearly so. When the surface has a complicated curvature, rows and columns can be more difficult to see. The Row, Column, and Row/Column buttons can be especially useful in this situation.

Name

Shows the name of the currently selected point. It is disabled if you have selected multiple points.

By default, the name is "Point" followed by a sequence number. You can use this field to give the point a name that you choose.

Hide

Click to hide the currently selected points.

Unhide All

Click to unhide all hidden points.

Fuse

Fuses a point to another point. (You can't fuse a CV to a point, or vice versa.) This is one way to connect two curves or surfaces. It is also a way to change the shape of curves and surfaces.

Fusing points does not combine the two point sub-objects. They are connected but remain distinct sub-objects that you can unfuse later.

Fused points behave as a single point until you unfuse them.

Fused points are displayed in a distinct color. The default is purple. (You can change this color using the Colors panel of the Customize User Interface dialog.)

Unfuse

Unfuses the fused points.

Extend

Extends a point curve. Drag from the end of a curve to add a new point and extend the curve.

Warning: When you add points with Extend, you lose the animation controllers for all points on the curve or surface.

Make Independent

Disabled if the point is independent. If the point is dependent, clicking this button makes it independent.

Warning: When you make a point independent, you lose the animation controllers for all objects that depend on it in turn.

Remove Animation

Removes animation controllers from the selected points.

Delete group

The buttons in this group delete one or more points.

Point

Deletes a single point (on a curve) or a row and column of points (on a surface).

Row

Deletes a row from a surface.

Col.

Deletes a column from a surface.

Warning: When you delete points, you lose the animation controllers for all points on the curve or surface.

Refine group

The buttons in this group refine point curves or surfaces by adding points to them.

Curve

Adds points to a point curve.

Surf Row

Adds a row of points to a point surface.

Surf Col.

Adds a column of points to a point surface.

Surf Row & Col.

Adds both a row and a column to a point surface; their intersection is where you click the surface.

Warning: When you add points, you lose the animation controllers for all points on the curve or surface.

Points Selected

This text field shows how many points are currently selected.