Unclear Koppen data to tree type correlation.

[andi-dogariu]

I am working to adapt my user-configurable default biome to also generate with appropriate trees.

I tried changing the "biomeData" property from double to the Biome type. and using a HashMap instead of the switch case method to make it easier for further extension. However, i see that for example Koppen values 4, 5, 7 get mapped to Biome.DESERT, but only 4 generates with trees.

Its not very clear to me how this is supposed to behave and how i should map the newer biomes that are not covered.