Restructure default/nodes.lua

mods/default/functions.lua

@@ -298,3 +298,42 @@ minetest.register_abm({
 	end
 })
 
+--
+-- Grass growing
+--
+
+minetest.register_abm({
+	nodenames = {"default:dirt"},
+	interval = 2,
+	chance = 200,
+	action = function(pos, node)
+		local above = {x=pos.x, y=pos.y+1, z=pos.z}
+		local name = minetest.get_node(above).name
+		local nodedef = minetest.registered_nodes[name]
+		if nodedef and (nodedef.sunlight_propagates or nodedef.paramtype == "light")
+				and nodedef.liquidtype == "none"
+				and (minetest.get_node_light(above) or 0) >= 13 then
+			if name == "default:snow" or name == "default:snowblock" then
+				minetest.set_node(pos, {name = "default:dirt_with_snow"})
+			else
+				minetest.set_node(pos, {name = "default:dirt_with_grass"})
+			end
+		end
+	end
+})
+
+minetest.register_abm({
+	nodenames = {"default:dirt_with_grass"},
+	interval = 2,
+	chance = 20,
+	action = function(pos, node)
+		local above = {x=pos.x, y=pos.y+1, z=pos.z}
+		local name = minetest.get_node(above).name
+		local nodedef = minetest.registered_nodes[name]
+		if name ~= "ignore" and nodedef
+				and not ((nodedef.sunlight_propagates or nodedef.paramtype == "light")
+				and nodedef.liquidtype == "none") then
+			minetest.set_node(pos, {name = "default:dirt"})
+		end
+	end
+})