1 files changed, 80 insertions, 0 deletions
diff --git a/biome_lib/growth.lua b/biome_lib/growth.lua
new file mode 100644
index 0000000..56ba4ef
--- /dev/null
+++ b/biome_lib/growth.lua
@@ -0,0 +1,80 @@
+local time_scale = ...
+
+-- The growing ABM
+
+function biome_lib:grow_plants(opts)
+
+	local options = opts
+
+	options.height_limit = options.height_limit or 5
+	options.ground_nodes = options.ground_nodes or { "default:dirt_with_grass" }
+	options.grow_nodes = options.grow_nodes or { "default:dirt_with_grass" }
+	options.seed_diff = options.seed_diff or 0
+
+	local n
+
+	if type(options.grow_plant) == "table" then
+		n = "multi: "..options.grow_plant[1]..", ..."
+	else
+		n = options.grow_plant
+	end
+
+	options.label = options.label or "biome_lib grow_plants(): "..n
+
+	if options.grow_delay*time_scale >= 1 then
+		options.interval = options.grow_delay*time_scale
+	else
+		options.interval = 1
+	end
+
+	minetest.register_abm({
+		nodenames = { options.grow_plant },
+		interval = options.interval,
+		chance = options.grow_chance,
+		label = options.label,
+		action = function(pos, node, active_object_count, active_object_count_wider)
+			local p_top = {x=pos.x, y=pos.y+1, z=pos.z}
+			local p_bot = {x=pos.x, y=pos.y-1, z=pos.z}
+			local n_top = minetest.get_node(p_top)
+			local n_bot = minetest.get_node(p_bot)
+			local root_node = minetest.get_node({x=pos.x, y=pos.y-options.height_limit, z=pos.z})
+			local walldir = nil
+			if options.need_wall and options.verticals_list then
+				walldir = biome_lib:find_adjacent_wall(p_top, options.verticals_list, options.choose_random_wall)
+			end
+			if (n_top.name == "air" or n_top.name == "default:snow")
+			  and (not options.need_wall or (options.need_wall and walldir)) then
+				-- corner case for changing short junglegrass
+				-- to dry shrub in desert
+				if n_bot.name == options.dry_early_node and options.grow_plant == "junglegrass:short" then
+					minetest.swap_node(pos, { name = "default:dry_shrub" })
+
+				elseif options.grow_vertically and walldir then
+					if biome_lib:search_downward(pos, options.height_limit, options.ground_nodes) then
+						minetest.swap_node(p_top, { name = options.grow_plant, param2 = walldir})
+					end
+
+				elseif not options.grow_result and not options.grow_function then
+					minetest.swap_node(pos, biome_lib.air)
+
+				else
+					biome_lib:replace_object(pos, options.grow_result, options.grow_function, options.facedir, options.seed_diff)
+				end
+			end
+		end
+	})
+end
+
+
+-- spawn_tree() on generate is routed through here so that other mods can hook
+-- into it.
+
+function biome_lib:generate_tree(pos, nodes_or_function_or_model)
+	minetest.spawn_tree(pos, nodes_or_function_or_model)
+end
+
+-- and this one's for the call used in the growing code
+
+function biome_lib:grow_tree(pos, nodes_or_function_or_model)
+	minetest.spawn_tree(pos, nodes_or_function_or_model)
+end