3D Compositing with Action > Action: Masks >
Adding a Gradient to a Mask

The gradient allows you to create a region of softness around the mask edge. It applies a gradient according to the distance of the borders from the mask spline. You can create a uniform gradient or customize it at different parts of the mask. The gradient can have two softness borders, one inside and one outside the mask edge.

To add a gradient to a mask:

1. Change the Edit mode to Add (A).
2. Hold down Shift and drag away from the spline.
3. Click on the mask spline.
4. (Optional) Do one of the following:
   - Shift-click on the spline again and drag in the same direction as the existing gradient to add a point in the gradient at a different position and distance from the mask.
   - Shift-click on the spline and drag away from it in the other direction to create a second gradient.

The position and distance of a gradient point from the mask spline can be controlled gesturally in Move mode (M) or in the Gradient tab.

Position
  Displays the relative position of the gradient control point in relation to the vertices. For example, if the control point is halfway between the third and fourth vertices, its value is 3.5.

Offset
  Displays the distance from the gradient spline to the garbage mask spline.

Gradient curve
  Displays the transparency distribution of the gradient. The y axis represents the percentage of transparency and the x axis represents the percentage of distance from the vertex to the spline. This curve can be animated. You can edit, add and delete points from the curve.