Two new automasking modes: "Brush Normal" and "View Normal." Brush Normal compares vertex normals to the initial sculpt normal, while View Normal of course compares with the view vector. Each of these modes have an angular limit and a falloff. There's also an "original normal" option, which needs a better name; "original normal" is actually already taken, but "automasking original normal" is a lot of characters. Not sure what to do here.