ed1a08382f
Now there is a single BVH traversal code with #ifdefs for various features. At runtime it will then select the appropriate variation to use depending if instancing, hair or motion blur is in use. This makes scenes without hair render a bit faster, especially after the minimum width feature was added. It's not the most beautiful code, but we can't use c++ templates and there were already 4 copies, adding 4 more to handle the hair case separately would be too much.