Add in slime chunks

mods/ENTITIES/mobs_mc/slime+magma_cube.lua

@@ -60,6 +60,182 @@ local spawn_children_on_die = function(child_mob, spawn_distance, eject_speed)
 	end
 end
 
+local function split_by_char (inputstr, sep, limit)
+	if sep == nil then
+		sep = "%d"
+	end
+	local t = {}
+
+	local i = 0
+	for str in string.gmatch(inputstr, "(["..sep.."])") do
+		i = i --+ 1
+		table.insert(t, tonumber(str))
+		if limit and i >= limit then
+			break
+		end
+	end
+	return t
+end
+
+
+local seed = minetest.get_mapgen_setting("seed")
+--local chunk_size = minetest.get_mapgen_setting("chunksize")
+
+local slime_chunk_match
+local x_modifier
+local z_modifier
+
+--Seed: "16002933932875202103"
+--Seed: "1807191622654296300" == cheese
+--Seed: "1" = 1
+local function process_seed (seed)
+	--minetest.log("chunk_size: " .. chunk_size)
+	minetest.log("seed: " .. seed)
+
+	local split_chars = split_by_char(tostring(seed), nil, 10)
+	minetest.log("Number of chars: " .. tostring(#split_chars))
+
+	slime_chunk_match = split_chars[1]
+	x_modifier = split_chars[2]
+	z_modifier = split_chars[3]
+
+
+	minetest.log("x_modifier: " .. tostring(x_modifier))
+	minetest.log("z_modifier: " .. tostring(z_modifier))
+	minetest.log("slime_chunk_match: " .. tostring(slime_chunk_match))
+	-- floor(x_or_z / chunk_size) + modifier
+end
+local processed = process_seed (seed)
+--process_seed (seed)
+
+
+-- Seed numbers are 0 - 9. Adding 1, and doubling it converts this to 2 - 20 (even numbers).
+-- This averages at roughly 10, so 1 in 10 chunks, or 10% is how frequent slime chunks are
+-- We then multiply by chunk_size * 1.8 (8) to map to co-ords, because if the lowest value is 2, then multiplied by 8 gives a chunk size of 16
+-- 2 * 8 = 16
+-- 4 * 8 = 32
+-- 6 * 8 = 48
+local function convert_to_chunk_value_old (input)
+	local total = 0
+
+	if input then
+		for _, v in pairs(input) do
+			v = (v + 1) * 2 * chunk_size * 1.8
+			total = total + v
+			minetest.log("v: " .. tostring(v))
+		end
+	end
+
+	minetest.log("total: " .. tostring(total))
+	minetest.log("average: " .. tostring(total/10))
+end
+
+local MAPBLOCK_SIZE = 16
+--local MAPBLOCK_SIZE = 3 * chunk_size
+
+local function convert_to_chunk_value (co_ord, modifier)
+	local converted = math.floor(math.abs(co_ord) / MAPBLOCK_SIZE)
+	--minetest.log("co_ord: " .. co_ord)
+
+	if modifier then
+		converted = (converted + modifier) % 10
+		minetest.log("with modifier: " .. converted)
+	else
+		minetest.log("converted: " .. converted)
+	end
+
+	converted = converted % 10
+	minetest.log("converted: " .. converted)
+	return converted
+end
+
+--assert(convert_to_chunk_value(-17) == 2, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(-16) == 1, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(-15) == 0, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(-1) == 0, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(0) == 0, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(1) == 0, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(15) == 0, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(16) == 1, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(31) == 1, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(32) == 2, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(1599) == 9, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(1600) == 0, "Incorrect convert_to_chunk_value result")
+
+assert(convert_to_chunk_value(0,9) == 9, "Incorrect convert_to_chunk_value result")
+assert(convert_to_chunk_value(16,5) == 6, "Incorrect convert_to_chunk_value result")
+
+-- 0, -1, -15
+-- convert_to_chunk_value_2(0)
+--[[
+convert_to_chunk_value(-16)
+convert_to_chunk_value(-15)
+convert_to_chunk_value(-14)
+convert_to_chunk_value(-1)
+convert_to_chunk_value(0)
+convert_to_chunk_value(1)
+convert_to_chunk_value(14)
+convert_to_chunk_value(15)
+convert_to_chunk_value(16)
+convert_to_chunk_value(29)
+convert_to_chunk_value(30)
+convert_to_chunk_value(31)
+convert_to_chunk_value(1500,9)
+convert_to_chunk_value(1501,9)
+convert_to_chunk_value(1516,9)
+convert_to_chunk_value(1531,9)
+convert_to_chunk_value(1649,9)
+]]--
+
+
+local function calculate_chunk_value (pos, x_mod, z_mod)
+	local chunk_val = math.abs(convert_to_chunk_value(pos.x, x_mod) - convert_to_chunk_value(pos.z, z_mod)) % 10
+	minetest.log("chunk_val: " .. tostring(chunk_val))
+	return chunk_val
+end
+
+assert(calculate_chunk_value(vector.new(0,0,0)) == 0, "calculate_chunk_value failed")
+assert(calculate_chunk_value(vector.new(0,0,0), 1, 1) == 0, "calculate_chunk_value failed")
+assert(calculate_chunk_value(vector.new(0,0,0), 2, 1) == 1, "calculate_chunk_value failed")
+assert(calculate_chunk_value(vector.new(64,0,16)) == (4-1), "calculate_chunk_value failed")
+assert(calculate_chunk_value(vector.new(16,0,64)) == (3), "calculate_chunk_value failed")
+assert(calculate_chunk_value(vector.new(-160,0,-160)) == 0, "calculate_chunk_value failed")
+--calculate_chunk_value(vector.new(0,0,16))
+--calculate_chunk_value(vector.new(15,0,31))
+--calculate_chunk_value(vector.new(32,0,32))
+--calculate_chunk_value(vector.new(15,0,15))
+
+
+local function is_slime_chunk(pos)
+	if not pos then return end
+
+	minetest.log("x: " ..pos.x ..  ", z:" .. pos.z)
+
+	local chunk_val = calculate_chunk_value (pos, x_modifier, z_modifier)
+
+	local slime_chunk = chunk_val == slime_chunk_match
+	minetest.log("Is slime chunk: " .. tostring(slime_chunk))
+	return slime_chunk
+end
+
+is_slime_chunk(vector.new(64,0,16))
+is_slime_chunk(vector.new(16,0,64))
+is_slime_chunk(vector.new(0,0,16))
+is_slime_chunk(vector.new(15,0,31))
+is_slime_chunk(vector.new(32,0,32))
+is_slime_chunk(vector.new(15,0,15))
+is_slime_chunk(vector.new(0,0,0))
+is_slime_chunk(vector.new(-150,0,-150))
+
+local check_position = function (pos)
+	minetest.log("Trying to spawn slime at pos: " .. dump(pos))
+
+	local slime_chunk = is_slime_chunk(pos)
+	minetest.log("spawn_position check: " .. dump(slime_chunk))
+
+	return slime_chunk
+end
+
 -- Slime
 local slime_big = {
 	description = S("Slime"),
@@ -112,6 +288,7 @@ local slime_big = {
 	spawn_small_alternative = "mobs_mc:slime_small",
 	on_die = spawn_children_on_die("mobs_mc:slime_small", 1.0, 1.5),
 	use_texture_alpha = true,
+	check_position = check_position,
 }
 mcl_mobs.register_mob("mobs_mc:slime_big", slime_big)
 
@@ -212,7 +389,8 @@ minetest.LIGHT_MAX+1,
 12000,
 4,
 cave_min,
-cave_max)
+cave_max,
+		nil, nil, check_position)
 
 mcl_mobs:spawn_specific(
 "mobs_mc:slime_tiny",
@@ -238,7 +416,8 @@ minetest.LIGHT_MAX+1,
 8500,
 4,
 cave_min,
-cave_max)
+cave_max,
+		nil, nil, check_position)
 
 mcl_mobs:spawn_specific(
 "mobs_mc:slime_small",
@@ -264,7 +443,8 @@ minetest.LIGHT_MAX+1,
 10000,
 4,
 cave_min,
-cave_max)
+cave_max,
+		nil, nil, check_position)
 
 mcl_mobs:spawn_specific(
 "mobs_mc:slime_big",
@@ -278,6 +458,7 @@ swamp_light_max,
 4,
 swamp_min,
 swamp_max)
+
 -- Magma cube
 local magma_cube_big = {
 	description = S("Magma Cube"),