Hans Goudey
ba3a0dc9ba
This commit adds a `normal` attribute on the polygon domain. Since normal data is derived data purely based off of the location of each face's vertices, it is exposed as a read-only attribute. After rB80f7f1070f17, this attribute can be interpolated to the other domains. Since this attribute is a special case compared to the others, the implementation subclasses `BuiltinAttributeProvider`. It's possible there is a better way to abstract this. Something else might also become apparent if we add similar read-only attributes. See rB2966871a7a891bf36 for why this is preferred over the previous implementation. Differential Revision: https://developer.blender.org/D10677