One my my favorite new features in Ae CC 2017.2 is the ability to change the mask mode from the keyboard, while you’re drawing it:
N – None
A – Add
S – Subtract
I – Intersect
L – Lighten
D – Darken
F – Difference
When you draw a new mask with the shape tools (Rectangle tool, Ellipse tool, etc.), you can press these keyboard shortcuts at any time while the mouse button is down.
When you draw a new mask with the Pen tool, you can only press these keyboard shortcuts when you close the mask: place the pointer over the closing vertex (usually the first vertex), click and hold the mouse button to close the mask, then press the mask mode keyboard shortcut before releasing the mouse button.
Open masks do not have a mode. These keyboard shortcuts do not work when drawing open masks with the Pen tool.
When you modify a closed mask, you can press these keyboard shortcuts at any time while you hold down the mouse button: when modifying mask points or the mask shape, when in free-transform mode, or when adding or modifying mask feather points.
(from https://blogs.adobe.com/creativecloud/after-effects-cc-april-2017-in-depth-new-features/?segment=dva )
Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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