The following properties appear in the Properties window depending on which tool you select from the Curve Tools tray.

Size

Sets the radius of the tool. By default, size is measured in world space units (for example, a brush Size of 100 = a radius of 100 centimeters). When Screen Pixels is selected, size is measured in screen space based pixels. Hotkeys: B + drag , or press the square bracket keys, [ to reduce size and ] to increase size.

For the Create Curve tool, Size controls the distance between points drawn to create the curve. Setting the Size to a larger value can make the curve appear segmented. Use a small brush size to produce high resolution curves.

Strength

Determines how much the tool affects the surface. Depending on the tool, this value represents either a percentage of the maximum power available or a height expressed in world space units. Hotkeys: M + drag , or press ; (to reduce strength) and ' (to increase strength).

Mirror

Reflects a stroke from one side of a model to the other, along the specified axis.

Plane

Available for the Curve Loop tool. See also Create precise 3D curves based on a plane.

By default, Plane is set to Free, which lets you add curves based on a line that you draw at any angle across the mesh.

To add curves perpendicular to a specific local or global axis, set Plane to the axis you want.

Snap

Available for the Curve Loop tool when Plane is set to a specific axis (not Free). When on, Mudbox snaps the preview plane to a numeric interval (specified in the Snap Distance field) as you click and drag to place curves. A HUD message displays as you drag to show the exact current position.

Snap Distance

(Available for the Curve Loop tool.) Lets you specify the interval at which to place curves as you click and drag with Snap turned on.

Stamp Spacing

Controls the stamp frequency/continuity on a stroke. Depending on the Size and Falloff settings for a tool, the Stamp Spacing can be set to a higher value to refine the tool behavior and improve the appearance of the stroke. The default setting is 6.25 and ranges between 0 and 100. The higher the setting, the more gaps appear on the stroke, depending on the tool settings.

For the Create Curve tool, the tool Size property works as a multiplier of the Stamp Spacing property.

Snap to Curve

When on, the tool snaps to an active curve when the cursor travels within the specified Distance. See also Sculpt or paint using curves.

Snap to Curve Distance

Sets the distance your cursor can be from a curve before snapping occurs. Default is 60.

Steady Stroke

Helps to produce a smoother stroke by filtering mouse/stylus movement. When on, a vector displays on the tool cursor and no stroke appears until you drag a distance equal to the length of the vector. The length of the vector is set by the Steady Stroke Distance property.

Steady Stroke Distance

Sets the length of the Steady Stroke vector on the tool cursor.

Extend/Close Tolerance

Sets the distance (in pixels) your cursor can be from a curve end point when the extend/connect cursor turns on. When this cursor is active, you can extend a curve or connect two curve end points together. Default is 10.

Draw on View Plane

When on, the Create Curve tool draws 2D curves on the plane defined by your screen only. No curves are drawn on your model. See also Create curves.

Create as Spline

Mudbox can represent curves as two different geometry types. When on (by default), Mudbox draws curves using the NURBS representation, which is an approximation of the curve drawn on the surface. (The level of approximation is controlled by the Follow value.) When off, curves are drawn as a polyline comprised of points stroked onto the surface. In most cases, the NURBS representation is preferable because it provides virtually unlimited resolution.

NOTE:If you export curves using FBX, the curves are exported as NURBS curves regardless of whether this option is on.

Follow

Determines how closely the curve matches what you draw on screen. The default value (100) makes the curve match your stroke exactly. Lower values allow for less exact, more relaxed, smoothed out curves.

Falloff along Length

Available for the Grab Curve, Smooth Curve, and Erase Curve tools.

When on, the effect of the brush falls off along the length of the curve, starting at the curve point closest to the brush center. When off, the falloff occurs according to how far each curve point is from the brush center.

Closest Curve Only

Available for the Grab Curve, Smooth Curve, and Erase Curve tools.

When on, the brushes affect only one curve at a time. When off, the brushes can affect more than one curve at once (depending on the brush Size, and the proximity of curves).