4. Switch to the Selection tool ( ), click anywhere in the Composition panel to deselect the
mask, and then click the first vertex that you created.Two direction handles extend off the smooth point. The angle and length of these handles control
the shape of the mask.
Tip
If you make a mistake, press Ctrl+Z (Windows) or Command+Z (macOS) to undo
your last action. You can also change the zoom level and use the Hand tool to
reposition the image in the Composition panel as you work.5. Drag the right handle of the first vertex around the screen. Notice how this changes the
shape of the mask. Notice also that the closer you drag the handle to another vertex, the less
the shape of the path is influenced by the direction handle of the first vertex, and the more it
is influenced by the direction handle of the second vertex.6. Once you are comfortable moving the handles, position the handle of the upper left vertex
as in the preceding figure. As you have seen, you can create very fluid shapes.About mask modes
Blending modes for masks (mask modes) control how masks within a layer interact with
one another. By default, all masks are set to Add, which combines the transparency values
of any masks that overlap on the same layer. You can apply one mode to each mask, but
you cannot change a mask’s mode over time.
The first mask you create interacts with the layer’s alpha channel. If that channel doesn’t
define the entire image as opaque, then the mask interacts with the layer frame. Each
additional mask that you create interacts with masks located above it in the Timeline panel.
The results of mask modes vary depending on the modes set for the masks higher up in the
Timeline panel. You can use mask modes only between masks in the same layer. Using
mask modes, you can create complex mask shapes with multiple transparent areas. For
example, you can set a mask mode that combines masks and sets the opaque area to the
regions where the masks intersect.