Use the automatic shape mask option
 
 
 

Turn on automatic shape creation for any curve creation tool.

  1. Open the Paint Panel, expand the section called Global Auto-Shape, and select the type of shape you wish to create.

    In this example we will create a mask shape to protect the side glass area of this image.

    From this moment on, all Alias curve creation tools will create mask shapes on the current layer.

    NoteEven tools such as Curve Edit > Create > Duplicate Curve and Object Edit > Offset will create new mask shapes, so take care to turn this option Off when you don’t want to create shapes.

    In this example, we will create a mask shape using the CV curve tool.

    As you place CV points to define the curve, the image layer mask automatically updates to form a closed mask region.

    NoteThe mask regions can be created with Fill set to Inside or Outside in the Shape Options section of the Paint Panel. This has the same effect as using Edit > Invert Layer in the Canvas Layer Editor.

  2. After the curve creation is complete, you can edit the curve using any of the standard modification tools.

    The primary limitation with this style of shape creation is that only single curves can be used to create a shape, whereas the Paint > Shape > tools allow multiple curves for shape creation, including holes in shapes.