Generate igloos on snow blocks

mods/MAPGEN/mcl_mapgen_core/init.lua

@@ -891,6 +891,7 @@ local perlin
 minetest.register_on_generated(function(minp, maxp, seed)
 	local chunk_has_desert_well = false
 	local chunk_has_desert_temple = false
+	local chunk_has_igloo = false
 	if maxp.y >= 2 and minp.y <= 0 then
 		-- Generate clay
 		-- Assume X and Z lengths are equal
@@ -988,6 +989,15 @@ minetest.register_on_generated(function(minp, maxp, seed)
 									end
 								end
 							end
+						elseif not chunk_has_igloo and nn == "mcl_core:snowblock" then
+							if math.random(1, 4400) == 1 then
+								-- Check surface
+								local surface = minetest.find_nodes_in_area({x=p.x,y=p.y-1,z=p.z}, {x=p.x+9, y=p.y-1, z=p.z+9}, "mcl_core:snowblock")
+								if #surface >= 63 then
+									mcl_structures.call_struct(p, "igloo")
+									chunk_has_igloo = true
+								end
+							end
 						end
 					end
 				end

mods/MAPGEN/mcl_structures/init.lua

@@ -171,7 +171,7 @@ end
 mcl_structures.generate_igloo_top = function(pos)
 	-- FIXME: This spawns bookshelf instead of furnace. Fix this!
 	-- Furnace does ot work atm because apparently meta is not set. :-(
-	local newpos = {x=pos.x,y=pos.y-2,z=pos.z}
+	local newpos = {x=pos.x,y=pos.y-1,z=pos.z}
 	local path = minetest.get_modpath("mcl_structures").."/build/igloo_top.mts"
 	minetest.place_schematic(newpos, path, "random", nil, true)
 end