+
+/*
+ PerlinNoise
+ */
+
+class LuaPerlinNoise
+{
+private:
+ int seed;
+ int octaves;
+ double persistence;
+ double scale;
+ static const char className[];
+ static const luaL_reg methods[];
+
+ // Exported functions
+
+ // garbage collector
+ static int gc_object(lua_State *L)
+ {
+ LuaPerlinNoise *o = *(LuaPerlinNoise **)(lua_touserdata(L, 1));
+ delete o;
+ return 0;
+ }
+
+ static int l_get2d(lua_State *L)
+ {
+ LuaPerlinNoise *o = checkobject(L, 1);
+ v2f pos2d = read_v2f(L,2);
+ lua_Number val = noise2d_perlin(pos2d.X/o->scale, pos2d.Y/o->scale, o->seed, o->octaves, o->persistence);
+ lua_pushnumber(L, val);
+ return 1;
+ }
+ static int l_get3d(lua_State *L)
+ {
+ LuaPerlinNoise *o = checkobject(L, 1);
+ v3f pos3d = read_v3f(L,2);
+ lua_Number val = noise3d_perlin(pos3d.X/o->scale, pos3d.Y/o->scale, pos3d.Z/o->scale, o->seed, o->octaves, o->persistence);
+ lua_pushnumber(L, val);
+ return 1;
+ }
+
+public:
+ LuaPerlinNoise(int a_seed, int a_octaves, double a_persistence,
+ double a_scale):
+ seed(a_seed),
+ octaves(a_octaves),
+ persistence(a_persistence),
+ scale(a_scale)
+ {
+ }
+
+ ~LuaPerlinNoise()
+ {
+ }
+
+ // LuaPerlinNoise(seed, octaves, persistence, scale)
+ // Creates an LuaPerlinNoise and leaves it on top of stack
+ static int create_object(lua_State *L)
+ {
+ int seed = luaL_checkint(L, 1);
+ int octaves = luaL_checkint(L, 2);
+ double persistence = luaL_checknumber(L, 3);
+ double scale = luaL_checknumber(L, 4);
+ LuaPerlinNoise *o = new LuaPerlinNoise(seed, octaves, persistence, scale);
+ *(void **)(lua_newuserdata(L, sizeof(void *))) = o;
+ luaL_getmetatable(L, className);
+ lua_setmetatable(L, -2);
+ return 1;
+ }
+
+ static LuaPerlinNoise* checkobject(lua_State *L, int narg)
+ {
+ luaL_checktype(L, narg, LUA_TUSERDATA);
+ void *ud = luaL_checkudata(L, narg, className);
+ if(!ud) luaL_typerror(L, narg, className);
+ return *(LuaPerlinNoise**)ud; // unbox pointer
+ }
+
+ static void Register(lua_State *L)
+ {
+ lua_newtable(L);
+ int methodtable = lua_gettop(L);
+ luaL_newmetatable(L, className);
+ int metatable = lua_gettop(L);
+
+ lua_pushliteral(L, "__metatable");
+ lua_pushvalue(L, methodtable);
+ lua_settable(L, metatable); // hide metatable from Lua getmetatable()
+
+ lua_pushliteral(L, "__index");
+ lua_pushvalue(L, methodtable);
+ lua_settable(L, metatable);
+
+ lua_pushliteral(L, "__gc");
+ lua_pushcfunction(L, gc_object);
+ lua_settable(L, metatable);
+
+ lua_pop(L, 1); // drop metatable
+
+ luaL_openlib(L, 0, methods, 0); // fill methodtable
+ lua_pop(L, 1); // drop methodtable
+
+ // Can be created from Lua (PerlinNoise(seed, octaves, persistence)
+ lua_register(L, className, create_object);
+ }
+};
+const char LuaPerlinNoise::className[] = "PerlinNoise";
+const luaL_reg LuaPerlinNoise::methods[] = {
+ method(LuaPerlinNoise, get2d),
+ method(LuaPerlinNoise, get3d),
+ {0,0}
+};
+