Default/trees: Combine sapling ABMs into one ABM

mods/default/trees.lua

@@ -1,7 +1,9 @@
 --
--- Grow trees
+-- Grow trees from saplings
 --
 
+-- 'Can grow' function
+
 local random = math.random
 
 local function can_grow(pos)
@@ -17,10 +19,12 @@ local function can_grow(pos)
 	return true
 end
 
--- Sapling ABMs
+
+-- Sapling ABM
 
 minetest.register_abm({
-	nodenames = {"default:sapling"},
+	nodenames = {"default:sapling", "default:junglesapling",
+		"default:pine_sapling", "default:acacia_sapling"},
 	interval = 10,
 	chance = 50,
 	action = function(pos, node)
@@ -28,70 +32,45 @@ minetest.register_abm({
 			return
 		end
 
+		local mapgen = minetest.get_mapgen_params().mgname
+		if node.name == "default:sapling" then
 			minetest.log("action", "A sapling grows into a tree at "..
 				minetest.pos_to_string(pos))
-		if minetest.get_mapgen_params().mgname == "v6" then
+			if mapgen == "v6" then
 				default.grow_tree(pos, random(1, 4) == 1)
 			else
 				default.grow_new_apple_tree(pos)
 			end
-	end
+		elseif node.name == "default:junglesapling" then
-})
-
-minetest.register_abm({
-	nodenames = {"default:junglesapling"},
-	interval = 11,
-	chance = 50,
-	action = function(pos, node)
-		if not can_grow(pos) then
-			return
-		end
-
 			minetest.log("action", "A jungle sapling grows into a tree at "..
 				minetest.pos_to_string(pos))
-		if minetest.get_mapgen_params().mgname == "v6" then
+			if mapgen == "v6" then
 				default.grow_jungle_tree(pos)
 			else
 				default.grow_new_jungle_tree(pos)
 			end
-	end
+		elseif node.name == "default:pine_sapling" then
-})
-
-minetest.register_abm({
-	nodenames = {"default:pine_sapling"},
-	interval = 12,
-	chance = 50,
-	action = function(pos, node)
-		if not can_grow(pos) then
-			return
-		end
-
 			minetest.log("action", "A pine sapling grows into a tree at "..
 				minetest.pos_to_string(pos))
-		if minetest.get_mapgen_params().mgname == "v6" then
+			if mapgen == "v6" then
 				default.grow_pine_tree(pos)
 			else
 				default.grow_new_pine_tree(pos)
 			end
-	end
+		elseif node.name == "default:acacia_sapling" then
-})
-
-minetest.register_abm({
-	nodenames = {"default:acacia_sapling"},
-	interval = 13,
-	chance = 50,
-	action = function(pos, node)
-		if not can_grow(pos) then
-			return
-		end
-
 			minetest.log("action", "An acacia sapling grows into a tree at "..
 				minetest.pos_to_string(pos))
 			default.grow_new_acacia_tree(pos)
 		end
+	end
 })
 
--- Appletree, jungletree function
+
+--
+-- Tree generation
+--
+
+-- Apple tree and jungle tree trunk and leaves function
 
 local function add_trunk_and_leaves(data, a, pos, tree_cid, leaves_cid,
 		height, size, iters, is_apple_tree)
@@ -150,7 +129,8 @@ local function add_trunk_and_leaves(data, a, pos, tree_cid, leaves_cid,
 	end
 end
 
--- Appletree
+
+-- Apple tree
 
 function default.grow_tree(pos, is_apple_tree, bad)
 	--[[
@@ -182,7 +162,8 @@ function default.grow_tree(pos, is_apple_tree, bad)
 	vm:update_map()
 end
 
--- Jungletree
+
+-- Jungle tree
 
 function default.grow_jungle_tree(pos, bad)
 	--[[
@@ -233,7 +214,8 @@ function default.grow_jungle_tree(pos, bad)
 	vm:update_map()
 end
 
--- Pinetree from mg mapgen mod, design by sfan5, pointy top added by paramat
+
+-- Pine tree from mg mapgen mod, design by sfan5, pointy top added by paramat
 
 local function add_pine_needles(data, vi, c_air, c_ignore, c_snow, c_pine_needles)
 	local node_id = data[vi]
@@ -373,7 +355,8 @@ function default.grow_pine_tree(pos)
 	vm:update_map()
 end
 
--- New tree
+
+-- New apple tree
 
 function default.grow_new_apple_tree(pos)
 	local path = minetest.get_modpath("default") .. "/schematics/apple_tree.mts"
@@ -381,6 +364,7 @@ function default.grow_new_apple_tree(pos)
 		path, 0, nil, false)
 end
 
+
 -- New jungle tree
 
 function default.grow_new_jungle_tree(pos)
@@ -389,6 +373,7 @@ function default.grow_new_jungle_tree(pos)
 		path, 0, nil, false)
 end
 
+
 -- New pine tree
 
 function default.grow_new_pine_tree(pos)
@@ -397,6 +382,7 @@ function default.grow_new_pine_tree(pos)
 		path, 0, nil, false)
 end
 
+
 -- New acacia tree
 
 function default.grow_new_acacia_tree(pos)