Implements control over lua random numbers

bh_random/src/bh_random.cpp

@@ -23,6 +23,7 @@ extern "C" {
 }
 
 static std::mt19937 generator;
+static std::mt19937 map_generator;
 static std::uniform_int_distribution<int> distribution(0, INT_MAX);
 
 extern "C" void
@@ -37,3 +38,16 @@ bh_rand(void)
 {
 	return distribution(generator);
 }
+
+extern "C" void
+bh_map_srand(unsigned int seed)
+{
+	map_generator.seed(seed);
+}
+
+
+extern "C" unsigned int
+bh_map_rand(void)
+{
+	return distribution(map_generator);
+}

bh_random/src/bh_random.h

@@ -23,3 +23,9 @@ bh_srand(unsigned int);
 
 unsigned int
 bh_rand(void);
+
+void
+bh_map_srand(unsigned int);
+
+unsigned int
+bh_map_rand(void);

data/chestgen.lua

@@ -1,6 +1,6 @@
 local room_builder = require "maproombuilder"
 local module = {}
-local random = math.random
+local random = map_random
 
 local textures = {
 	"Items/Chest0.png",

data/mapgen.lua

@@ -5,8 +5,8 @@ local chest_gen = require "chestgen"
 
 -- Setting up some functions
 local time = os.time
-local random = math.random
-local randomseed = math.randomseed
+local random = map_random
+local randomseed = map_randomseed
 
 -- CONSTANTS
 local UP	= 1

data/maproombuilder.lua

@@ -1,5 +1,5 @@
 -- FUNCTIONS
-local random = math.random
+local random = map_random
 
 -- CONSTANTS
 local UP	= 1
@@ -536,7 +536,7 @@ function module.load_textures(map)
 
 	local seed = get_random_seed(CURRENT_LEVEL);
 	info("Map room random seed: " .. seed)
-	math.randomseed(seed)
+	map_randomseed(seed)
 	local xo = (random(3) - 1) * 112
 	local yo = (random(8)) * 48
 

data/monstergen.lua

@@ -1,6 +1,6 @@
 local room_builder = require "maproombuilder"
 local module = {}
-local random = math.random
+local random = map_random
 
 local texturePaths = {
 	aquatic0 = "Characters/Aquatic0.png",

data/trapgen.lua

@@ -1,6 +1,6 @@
 local room_builder = require "maproombuilder"
 local module = {}
-local random = math.random
+local random = map_random
 
 local textures = {
 	"Objects/Trap1.png",

src/map_lua.c

@@ -36,6 +36,7 @@
 #include "item.h"
 #include "item_builder.h"
 #include "random.h"
+#include "bh_random.h"
 
 static
 lua_State* load_lua_state(void)
@@ -475,6 +476,22 @@ l_get_random_seed(lua_State *L)
 	return 1;
 }
 
+static int
+l_set_random_seed(lua_State *L)
+{
+	unsigned int seed = (unsigned int) luaL_checkinteger(L, 1);
+	bh_map_srand(seed);
+	return 0;
+}
+
+static int
+l_get_random(lua_State *L)
+{
+	unsigned int max = (unsigned int) luaL_checkinteger(L, 1);
+	lua_pushnumber(L, (bh_map_rand() % max) + 1);
+	return 1;
+}
+
 static Map*
 generate_map(unsigned int level, const char *file, GameMode gameMode, SDL_Renderer *renderer)
 {
@@ -534,6 +551,12 @@ generate_map(unsigned int level, const char *file, GameMode gameMode, SDL_Render
 	lua_pushcfunction(L, l_get_random_seed);
 	lua_setglobal(L, "get_random_seed");
 
+	lua_pushcfunction(L, l_set_random_seed);
+	lua_setglobal(L, "map_randomseed");
+
+	lua_pushcfunction(L, l_get_random);
+	lua_setglobal(L, "map_random");
+
 	lua_pushinteger(L, level);
 	lua_setglobal(L, "CURRENT_LEVEL");