add vm function to increase the speed of creating own mountains

update

init.lua

@@ -173,19 +173,71 @@ default.cool_lava_source = function()end
 default.cool_lava_flowing = function()end
 
 lavacooling_abm("default:lava_source", WATER, "default:obsidian")
+
+local function cool_wf_vm(pos)
+	local t1 = os.clock()
+	local minp = vector.subtract(pos, 10)
+	local maxp = vector.add(pos, 10)
+	local manip = minetest.get_voxel_manip()
+	local emerged_pos1, emerged_pos2 = manip:read_from_map(minp, maxp)
+	local area = VoxelArea:new({MinEdge=emerged_pos1, MaxEdge=emerged_pos2})
+	local nodes = manip:get_data()
+
+	local basalt = minetest.get_content_id("default:basalt")
+	local cobble = minetest.get_content_id("default:cobble")
+	local lava = minetest.get_content_id("default:lava_flowing")
+
+	for x = minp.x, maxp.x do
+		for y = minp.y, maxp.y do
+			for z = minp.z, maxp.z do
+				local p = {x=x, y=y, z=z}
+				local p_p = area:indexp(p)
+				if nodes[p_p] == lava then
+					if find_coolingnodes(WATER, p) then
+						if y < -10+math.random(5) then
+							nodes[p_p] = basalt
+						else
+							nodes[p_p] = cobble
+						end
+					end
+				end
+			end
+		end
+	end
+				
+
+	manip:set_data(nodes)
+	manip:write_to_map()
+	print(string.format("[lavacooling] cooled at ("..pos.x.."|"..pos.y.."|"..pos.z..") after ca. %.2fs", os.clock() - t1))
+	local t1 = os.clock()
+	manip:update_map()
+	print(string.format("[lavacooling] map updated after ca. %.2fs", os.clock() - t1))
+end
+
+local del1 = 0
+local count = 0
+
 minetest.register_abm ({
 	nodenames = {"default:lava_flowing"},
 	interval = 0,
 	chance = 1,
 	action = function (pos)
-		if find_coolingnodes(WATER, pos) then
+		local del2 = tonumber(os.clock())
+		if del2-del1 < 0.1
+		and count > 10 then
+			cool_wf_vm(pos)
+			count = 0
+		elseif find_coolingnodes(WATER, pos) then
 			if pos.y < -10+math.random(5) then
 				coolnode("default:basalt", pos)
 			else
 				coolnode("default:cobble", pos)
 			end
-
+			if del2-del1 < 0.1 then
+				count = count+1
+			end
 		end
+		del1 = del2
 	end,
 })