add tree life cycle dynamics to game data

[Sigra]

Implement an immovable program command for seeding an immovable in a nearby location. The command has 2 parameters; the immovable type to seed and the probability of spreading one step further away.

The attached patch implements the game logic part. With this patch, game designers can experiment with trees that reproduce. Note that execution of immovable programs may not take place as intended because of bug #1792379. So if trees do not grow, they will not seed either. Test with a map where where tree growth actually works, such as tree-growth.wmf (attached to the mentioned bug). Note that game data must be modified to see any effect of this patch.

[Sigra (sigra)]

Revision 3317 enhanced the capabilities of the game engine to handle this. Now the game data part remains.

The attached patch implements this for the trees in greenland. The implementation is still quite boring and unbalanced. All trees have very similar life cycles and trees are generally a bit too successful. This should be adjusted so that the different trees have different advantages and disadvantages. Some should seed often, some should spread their seeds far, some should live long, some should grow fast. (Those who have used the editor are familiar with the rule that trees can be on any terrain type, so do not let that surprise you. The only reason that trees were not so often seen on water in the past was that the map designers did not put them there and the forester could not go there.)
File Added: game_data_tree_dynamics-1.diff

[Sigra (sigra)]

This updated patch adds some variation among the the trees. Maybe it could be a little better balanced, but all tree species can at least survive a few hours of game time. But of course in the long run, one species will take over. That is just the law of evolution. To keep several species alive together, we would have to specialize them on different ecological niches. That would mean that we would have to give different species slight advantages on different terrain types. However there is a special niche already; forested areas. Some species benefit from lumberjacks (the species that grow fast and have some reproduction before they become full-sized).
File Added: game_data_tree_dynamics-2.diff

[Sigra (sigra)]

The file game_data_tree_dynamics-2.diff was added: patch for the game data part (only greenland)

[Sigra (sigra)]

Implemented in revision 3591.