Add poplar tree

Poplars exist in two kinds: small and large trees. Both use the same
nodes, except for the sapling. Poplar leaves may drop one or the
other sapling.

Poplar trees require a humid environment, and water nearby.
Provided there is water, an occasional poplar will grow under less humid
conditions.

LICENSE

@@ -7,13 +7,14 @@ All source code:
 Date & cocos palm code (date_palm.lua, cocos_palm.lua)
 	© 2016, Rogier <rogier777@gmail.com>
 	Published under the terms and conditions of the WTFPL.
-All date & date palm textures, date-based food, cocos flower & green coconuts:
+All date & date palm textures, date-based food, cocos flower & green coconuts,
+and all poplar textures:
 	© 2016, Rogier <rogier777@gmail.com>
 	Published under the terms and conditions of CC-BY-SA-3.0 Unported.
 	- Three of the date palm textures are modifications of existing moretrees textures
 	- The green coconuts are a modification of the brown coconut
 	- The date cake batter is a modification of the acorn muffin batter
-All sapling textures (textures/*_sapling.png):
+All other sapling textures (textures/*_sapling.png):
 	© 2013, Tim Huppertz <mitroman@naturalnet.de>
 	Published under the terms and conditions of CC-BY-SA-3.0 Unported.
 All other textures:

biome_defs.lua

@@ -196,6 +196,97 @@ moretrees.cedar_biome = {
 	max_count = 10,
 }
 
+
+-- Poplar requires a lot of water.
+moretrees.poplar_biome = {
+	surface = "default:dirt_with_grass",
+	avoid_nodes = moretrees.avoidnodes,
+	avoid_radius = 6,
+	seed_diff = 341,
+	min_elevation = 0,
+	max_elevation = 50,
+	near_nodes = {"default:water_source"},
+	near_nodes_size = 15,
+	near_nodes_vertical = 5,
+	near_nodes_count = 1,
+	humidity_min = -0.7,
+	humidity_max = -1,
+	rarity = 50,
+	max_count = 15,
+}
+
+-- The humidity requirement it quite restrictive (apparently).
+-- Spawn an occasional poplar elsewhere.
+moretrees.poplar_biome_2 = {
+	surface = "default:dirt_with_grass",
+	avoid_nodes = moretrees.avoidnodes,
+	avoid_radius = 6,
+	seed_diff = 341,
+	min_elevation = 0,
+	max_elevation = 50,
+	near_nodes = {"default:water_source"},
+	near_nodes_size = 15,
+	near_nodes_vertical = 4,
+	near_nodes_count = 10,
+	humidity_min = 0.1,
+	humidity_max = -0.6,
+	rarity = 50,
+	max_count = 1,
+}
+
+-- Subterranean lakes provide enough water for poplars to grow
+moretrees.poplar_biome_3 = {
+	surface = "default:dirt_with_grass",
+	avoid_nodes = moretrees.avoidnodes,
+	avoid_radius = 6,
+	seed_diff = 342,
+	min_elevation = 0,
+	max_elevation = 50,
+	near_nodes = {"default:water_source"},
+	near_nodes_size = 1,
+	near_nodes_vertical = 25,
+	near_nodes_count = 1,
+	humidity_min = -0.5,
+	humidity_max = -1,
+	rarity = 0,
+	max_count = 30,
+}
+
+moretrees.poplar_small_biome = {
+	surface = "default:dirt_with_grass",
+	avoid_nodes = moretrees.avoidnodes,
+	avoid_radius = 4,
+	seed_diff = 343,
+	min_elevation = 0,
+	max_elevation = 50,
+	near_nodes = {"default:water_source"},
+	near_nodes_size = 10,
+	near_nodes_vertical = 5,
+	near_nodes_count = 1,
+	humidity_min = -0.7,
+	humidity_max = -1,
+	rarity = 50,
+	max_count = 10,
+}
+
+moretrees.poplar_small_biome_2 = {
+	surface = "default:dirt_with_grass",
+	avoid_nodes = moretrees.avoidnodes,
+	avoid_radius = 4,
+	seed_diff = 343,
+	min_elevation = 0,
+	max_elevation = 50,
+	near_nodes = {"default:water_source"},
+	near_nodes_size = 10,
+	near_nodes_vertical = 4,
+	near_nodes_count = 5,
+	humidity_min = 0.1,
+	humidity_max = -0.6,
+	rarity = 50,
+	max_count = 3,
+}
+
+
 moretrees.fir_biome = {
 	surface = "default:dirt_with_grass",
 	avoid_nodes = moretrees.avoidnodes,

default_settings.txt

@@ -15,6 +15,7 @@ moretrees.enable_birch			= true
 moretrees.enable_spruce			= true
 moretrees.enable_jungle_tree	= true
 moretrees.enable_fir			= true
+moretrees.enable_poplar			= true
 moretrees.enable_beech			= false
 
 -- set this to true to make moretrees spawn saplings at mapgen time instead

init.lua

@@ -97,6 +97,8 @@ if moretrees.spawn_saplings then
 	moretrees.spawn_jungletree_object = "moretrees:jungletree_sapling_ongen"
 	moretrees.spawn_fir_object = "moretrees:fir_sapling_ongen"
 	moretrees.spawn_fir_snow_object = "snow:sapling_pine"
+	moretrees.spawn_poplar_object = "moretrees:poplar_sapling_ongen"
+	moretrees.spawn_poplar_small_object = "moretrees:poplar_small_sapling_ongen"
 else
 	moretrees.spawn_beech_object = moretrees.beech_model
 	moretrees.spawn_apple_tree_object = moretrees.apple_tree_model
@@ -113,6 +115,8 @@ else
 	moretrees.spawn_jungletree_object = "moretrees.grow_jungletree"
 	moretrees.spawn_fir_object = "moretrees.grow_fir"
 	moretrees.spawn_fir_snow_object = "moretrees.grow_fir_snow"
+	moretrees.spawn_poplar_object = moretrees.poplar_model
+	moretrees.spawn_poplar_small_object = moretrees.poplar_small_model
 end
 
 if moretrees.enable_beech then
@@ -175,6 +179,14 @@ if moretrees.enable_fir then
 	end
 end
 
+if moretrees.enable_poplar then
+	biome_lib:register_generate_plant(moretrees.poplar_biome, moretrees.spawn_poplar_object)
+	biome_lib:register_generate_plant(moretrees.poplar_biome_2, moretrees.spawn_poplar_object)
+	biome_lib:register_generate_plant(moretrees.poplar_biome_3, moretrees.spawn_poplar_object)
+	biome_lib:register_generate_plant(moretrees.poplar_small_biome, moretrees.spawn_poplar_small_object)
+	biome_lib:register_generate_plant(moretrees.poplar_small_biome_2, moretrees.spawn_poplar_small_object)
+end
+
 -- Code to spawn a birch tree
 
 function moretrees.grow_birch(pos)

node_defs.lua

@@ -12,6 +12,8 @@ moretrees.treelist = {
 	{"date_palm",		"Date Palm Tree",	"date_palm_fruit_trunk",	"Date Palm Tree",		{0, 0, 0, 0, 0, 0},	0.0 },
 	{"spruce",		"Spruce Tree",		"spruce_cone",	"Spruce Cone",	{-0.2, -0.5, -0.2, 0.2, 0, 0.2},	0.8 },
 	{"cedar",		"Cedar Tree",		"cedar_cone",	"Cedar Cone",	{-0.2, -0.5, -0.2, 0.2, 0, 0.2}, 0.8 },
+	{"poplar",		"Poplar Tree"},
+	{"poplar_small",	"Poplar Tree"},
 	{"willow",		"Willow Tree"},
 	{"rubber_tree",	"Rubber Tree"},
 	{"fir",			"Douglas Fir",		"fir_cone",		"Fir Cone",		{-0.2, -0.5, -0.2, 0.2, 0, 0.2},	0.8 },
@@ -72,6 +74,7 @@ for i in ipairs(moretrees.treelist) do
 
 	if treename ~= "jungletree"  -- the default game provides jungle tree, acacia, and pine trunk/planks nodes.
 		and treename ~= "acacia"
+		and treename ~= "poplar_small"
 		and treename ~= "pine" then
 
 		saptex = "moretrees_"..treename.."_sapling.png"
@@ -273,6 +276,43 @@ for i in ipairs(moretrees.treelist) do
 	end
 end
 
+-- Add small poplar saplings
+
+local poplar_sapling = minetest.registered_nodes["moretrees:poplar_sapling"]
+local poplar_sapling_ongen = minetest.registered_nodes["moretrees:poplar_sapling_ongen"]
+local poplar_small_sapling = {}
+local poplar_small_sapling_ongen = {}
+for k,v in pairs(poplar_sapling) do
+	poplar_small_sapling[k] = v
+end
+for k,v in pairs(poplar_sapling_ongen) do
+	poplar_small_sapling_ongen[k] = v
+end
+poplar_small_sapling.tiles = {"moretrees_poplar_small_sapling.png"}
+poplar_small_sapling.inventory_image = "moretrees_poplar_small_sapling.png"
+poplar_small_sapling_ongen.tiles_ongen = {"moretrees_poplar_small_sapling.png"}
+poplar_small_sapling_ongen.inventory_image_ongen = "moretrees_poplar_small_sapling.png"
+poplar_small_sapling_ongen.drop = "moretrees:poplar_small_sapling"
+minetest.register_node("moretrees:poplar_small_sapling", poplar_small_sapling)
+minetest.register_node("moretrees:poplar_small_sapling_ongen", poplar_small_sapling_ongen)
+if moretrees.spawn_saplings then
+	table.insert(moretrees.avoidnodes, "moretrees:poplar_sapling")
+	table.insert(moretrees.avoidnodes, "moretrees:poplar_small_sapling_ongen")
+end
+
+local poplar_leaves_drop = minetest.registered_nodes["moretrees:poplar_leaves"].drop
+minetest.override_item("moretrees:poplar_leaves", {
+	drop = {
+		max_items = poplar_leaves_drop.maxitems,
+		items = {
+			{items = {"moretrees:poplar_sapling"}, rarity = 1.33 * poplar_leaves_drop.items[1].rarity },
+			{items = {"moretrees:poplar_small_sapling"}, rarity = 1.33 * poplar_leaves_drop.items[1].rarity },
+			{items = {"moretrees:poplar_leaves"} }
+		}
+	}
+})
+
+
 -- Extra nodes for jungle trees:
 
 local jungleleaves = {"yellow","red"}

tree_biomes.txt

@@ -18,6 +18,7 @@ willow		- 5 to + 5	    n/a		water, 15	   5	dirt_with grass		337		20
 acacia		    n/a		    n/a		  n/a		n/a	dirt_with_grass,
 									desert_sand		n/a		15
 rubber		- 5 to + 5	 above +32	water, 15	  10	dirt_with_grass		338		20
+poplar		    n/a		-10 to +26	water, 15h,5v	   1	dirt_with_grass		341,342,343	10
 
 beech		    n/a		    n/a		  n/a		n/a	dirt_with_grass		2		10
 

tree_models.lua

@@ -43,6 +43,37 @@ moretrees.oak_model={
 	fruit_chance=3,
 }
 
+moretrees.poplar_model={
+	axiom="TTTaaBCCCCCCCCCCCcccBBB[[f]&&G++f++Gf++Gf++Gf++G--]G[[f]&&G++f++Gf++Gf++Gf++G--]Gff",
+	rules_a="T",
+	rules_b="[[T]&&G++f++ff++ff++ff++f--]G",
+	rules_c="[[T]&&G++f++ff++ff++ff++f--G++[d]G[d]G++G[d]G[d]G[d]G++G[d]G[d]G[d]G++G[d]G[d]G[d]G++G[d]G]G",
+	rules_d="f",
+	trunk="air",
+	trunk="moretrees:poplar_trunk",
+	leaves="moretrees:poplar_leaves",
+	angle=45,
+	iterations=0,
+	random_level=0,
+	trunk_type="single",
+	thin_branches=false,
+}
+
+moretrees.poplar_small_model={
+	axiom="TT[T]BCCCCccBBff",
+	rules_a="T",
+	rules_b="[[f]&&G++f++Gf++Gf++Gf++G--]G",
+	rules_c="[[T]&&G++f++[d]Gf++[d]Gf++[d]Gf++[d]G--]G",
+	rules_d="f",
+	trunk="moretrees:poplar_trunk",
+	leaves="moretrees:poplar_leaves",
+	angle=45,
+	iterations=0,
+	random_level=0,
+	trunk_type="single",
+	thin_branches=false,
+}
+
 moretrees.sequoia_model={
 	axiom="FFFFFFFFFFddccA///cccFddcFA///ddFcFA/cFFddFcdBddd/A/ccdcddd/ccAddddcFBcccAccFdFcFBcccc/BFdFFcFFdcccc/B",
 	rules_a="[&&&GGF[++^FFdd][--&Fddd]//Fdd[+^Fd][--&Fdd]]////[&&&GGF[++^FFdd][--&Fddd]//Fdd[+^Fd][--&Fdd]]////[&&&GGF[++^FFdd][--&Fddd]//Fdd[+^Fd][--&Fdd]]",