There's a whole bunch of quotes and information from the Black & White 2 development team on http://www.lionhead.com/teambw/makingof.html. They explain where they get their inspiration from or go into detail on certain features or technology. Today Matthew Hanlon, Game Programmer on Black&White 2 explains how forests and trees work.
Matthew Hanlon - Game Programmer: "Forests are just one of the many background simulations that make up the world of Black & White 2; we wanted the simulation to act like you'd expect a real forest to. Trees in the forest are split into those which are still growing and fully grown mature trees. The mature trees drop seeds which, under the right conditions, sprout into saplings, so the forest will naturally expand and produce new trees. If, for example, you pull all the trees out of the centre of a forest, over time new trees will grow into the space filling in the hole.
Our foresters have become a bit more eco-aware in B&W2; when looking for a tree to cut down they'll favour the mature trees over those that are still growing - allowing the forest to sustain itself. The larger trees mean more wood resource for you, and with the resource miracles gone, you need those trees.
One of the new concepts introduced to BW2 is fertility. The ground on a land ranges from ultra-fertile to totally unfertile barren land where nothing will grow. Fertility is incorporated into our forest simulation with the fertility of the land affecting the growth rate or the saplings, the more fertile it is the faster they'll grow - seeds which fall on infertile land don't produce saplings. Fertility affects other things in the game, but I'm not going to tell you about them here.
Our 3D coders and artists have done a fantastic job with the tree models, like the rest of the world tree change to reflect the alignment of the player. Additionally they've developed a technique to model a tree's growth, with the amount of foliage on the tree changing with its age. All adding to the sense of a real forest, and to think before starting work here, I would have never even considered how a forest works..."