Near the top of this page, in the Creating Masks section, it states the following:
"Convert a shape path to a mask path by copying the shape’s path to the Mask Path property."
How can one do that? Shapes do not have shape paths. They have property groups with the word "path" in their name, but you can't copy/paste a property group to a Mask path.
It would be great to get an explanation about copying/pasting shapes onto Mask Paths because if you use a shape tool to create a mask on a layer directly, you can't adjust the roundness, points, and/or radius after creating the mask.
I don't think either approach accomplishes what I am trying to do. Just as when using a shape tool on an existing layer to create a mask, none of these approaches lets me alter a shape path after creating it, in terms of number of points, inner/outer radius and inner/outer roundness. Nor can I animate those characteristics.
The Help file creates the impression that you can copy/paste a Shape path from a Shape layer. If that were true, I could create a shape, copy/paste that path to a mask path, keyframe it, go back to the original shape layer, change its propertie and copy/paste that new shape path to the mask path at a different time, thus morphing from one shape to another. I don't see any way to do that.