Leaf Litter Distribution Tweaks

In the 1/8 "ambient features" snapshot, leaf litter generation appears mostly random, with perhaps slightly greater density beneath leaf blocks and slightly lesser density on blocks exposed to the sky. However, the density appears similar in either case, and the fact that not all 4 components of each litter are always populated means we see a lot of grass poking through even the densest sections. The result is uniform-looking leaf coverage.

I think it would be more accurate and aesthetically pleasing to cluster the leaves more densely beneath the trees - both in terms of how many blocks are covered and how many of the 4 slots are populated. This would give the appearance of leaf piles rather than a totally even spread. 

A similar effect could be achieved by having leaf litter generate in large, continuous patches, like flowers in Flower Forests, using Perlin noise. The noise value could determine the average number of the 4 leaf slots populated, so we get even transitions from clearly higher to clearly lower density areas.