Deform Tools

Displaying Deformation Curves

You can display one or both of the deformation curves by using the curve display buttons near the top left corner of the Deformation dialog.

Turn on the following buttons to display deformation curves:

• Display X Axis: Displays only the X axis deformation curve in red.
• Display Y Axis : Displays only the Y axis deformation curve in green.
• Display XY Axes: Displays X axis and Y axis deformation curves together, each using its own color.

If a deformation uses only one curve, such as Twist, buttons for working with a second curve are disabled. The disabled buttons are: Make Symmetrical, Display X Axis, Display Y Axis, Display XY Axes, and Swap Deform Curves.

Setting Curve Symmetry

You can apply the same deformation to both axes of a shape using the Make Symmetrical button.

Make Symmetrical is both an action button and a curve editing mode. Turning Make Symmetrical on has the following effect:

• When a single curve is displayed, it copies the displayed deformation curve to the curve for the hidden axis.
• When both axes are displayed, the Apply Symmetry dialog appears. Click the button for the curve you want applied to both axes.
• Any changes you make to the selected curve are duplicated on the other curve.

When Make Symmetrical is not selected, curve editing is applied only to the selected curve.

Swapping Deformation Curves

Use Swap Curves to copy curves between the X axis and Y axis. This button has no effect when the Make Symmetrical button is selected.

Click Swap Curves to copy the X axis curve to the Y axis, and the Y axis curve to the X axis. It doesn't matter which curve is currently displayed or selected.

Editing Deformation Curves

When you first apply a deformation, you start with a straight line using a constant value. To produce more elaborate curves, you insert control points and change their properties.

Use the buttons in the center of the Deformation dialog toolbar to insert and change deformation curve control points.

• Control Point Types: Control points on a deformation curve can produce curves or sharp corners depending on the control point type. The three types are:
• Corner: Non-adjustable linear control point producing a sharp corner.
• Bezier Corner: Adjustable Bezier control point with discontinuous tangent handles set to produce a sharp corner. This type produces a curve that starts out looking like the corner type but it has control handles like the Bezier Smooth type.
• Bezier Smooth: Adjustable Bezier control point with locked continuous tangent handles set to produce a smooth curve.
• Selecting Control Points: Use the Move Control Point and Scale Control Point buttons with standard 3DS MAX selection techniques to select control points.

Inserting and Deleting Control Points

The most basic change you can make to a deformation curve is the insertion and deletion of control points.

• Inserting Control Points: The Insert Control Point flyout contains two buttons for inserting two different control point types.
• If you know which type of control point you need, you can save time by using the insert button for that type of point.
• If you are not sure which type of control point you need, or change your mind later, you can convert the point to the other type.

Both Insert Control Point buttons put you in an insertion mode. Right-click or choose another button to exit the mode.

• Insert Corner Point: Click anywhere on a deformation curve to insert a corner control point at that location.
• Insert Bezier Point: Click anywhere on a deformation curve to insert a modified Bezier control point at that location. The tangent handles of the Bezier control point are set to maintain the shape of the original curve before the point was inserted.
• Deleting Control Points: You can choose between two methods of deleting control points from your deformation curve.
• Delete Control Point: Select one or more control points and click this button to delete them.

Shortcut: Delete Control Point=DELETES

• Reset Curve: Deletes all but the end control points and sets the curves back to their default values.

Transforming Control Points

You use the Move and Scale buttons in the Deformation dialog toolbar to transform control points and Bezier tangent handles.

• Moving Control Points: The Move Control Point flyout contains three buttons for moving control points and Bezier handles.

Control points are constrained horizontally to stay between the points to either side. The amount of horizontal constraint is determined by the control point type:

• Corner control points can be moved very close together, until one is directly above the other.
• Bezier control points are constrained to get no closer than the length of their tangent handles.
• Move Control Point: Changes both the amount of deformation and the location where the deformation occurs.
• Move Vertical: Changes the amount of deformation without changing the location where the deformation occurs.
• Move Horizontal: Changes the location where the deformation occurs without changing the amount of deformation.

You can also move single control points by entering values in the control point Position and Amount fields at the bottom of the Deformation dialog.

• Moving Bezier Tangent Handles: You can use the Move Control Point buttons to drag a tangent handle's angle and magnitude on Bezier Smooth and Bezier Corner vertices.

Dragging a tangent handle has the following constraints:

• Tangent angles cannot move beyond vertical. This prevents deformation curves from doubling back on themselves.
• Tangent magnitudes cannot move beyond the preceding or next control point on the path.
• Pressing SHIFT while moving a Bezier Smooth tangent handle converts the control point to a Bezier Corner type.
• Scaling Control Points: You can scale the value of one or more selected control points using the Scale Control Point button. Use this button when you want to change only the deformation amount of selected control points while maintaining their relative ratio of values.
• Scale Control Point: Scales the value of selected control points with respect to 0.
• Drag down to reduce values.
• Drag up to increase values.

How To

To drag Bezier tangent handles:

1. Select one or more Bezier Smooth or Bezier Corner control points to display their tangent handles.
2. Click one of the Move Control Point buttons.
3. Drag on any tangent handle.
• Only the tangent handle you drag is affected. Tangent handles on other selected control points do not change.
• If the tangent handle you drag is part of a Bezier Smooth control point, both handles move to maintain the Bezier Smooth type.
• If the tangent handle you drag is part of a Bezier Corner control point, only that single handle moves.

To move a control point using the Position and Amount fields:

1. Select a single control point.
2. Do one of the following:
• Move the control point horizontally by entering a value in the Position field.
• Move the control point vertically by entering a value in the Amount field.

Changing Control Point Types:

You can change control point types at any time by Right-clicking on a selection of one or more control points.

To change the control point type:

1. Select one or more control points.
2. Right-click any selected control point.
3. Choose a control point type from the pop-up menu.

The following conditions apply to changing control point types:

• The first and last control points must use the Corner or Bezier Corner type.
• Converting a Bezier Smooth point to a Bezier Corner point unlocks the tangent handles but does not change their position. The curve appears smooth until you drag one of the tangent handles.
• Converting a Bezier Corner point, or an inserted Bezier point, to Bezier Smooth locks the tangent handles and changes their position and magnitude. The handles are rotated to the average between their two angles. The handle magnitudes are averaged and set equal.