Don't save and load maps, save and load seeds of maps. Load via command line option.

[plomrogue] / roguelike.c

diff --git a/roguelike.c b/roguelike.c
index 532ae70ec08993b5b8666773e3f725f10a3e1614..7abc32337e876e671993e29c6924c3b0db29f218 100644 (file)
--- a/roguelike.c
+++ b/roguelike.c
@@ -1,12 +1,50 @@
 #include <stdlib.h>
+//#include <limits.h>
 #include <stdint.h>
 #include <ncurses.h>
 #include <string.h>
+#include <time.h>
+#include <unistd.h>
 #include "windows.h"
 #include "draw_wins.h"
 #include "roguelike.h"
 #include "keybindings.h"
 
+uint16_t rrand(char use_seed, uint32_t new_seed) {
+// Pseudo-random number generator (LGC algorithm). Use instead of rand() to ensure portable predictability.
+  static uint32_t seed = 0;
+  if (0 != use_seed)
+    seed = new_seed;
+  seed = ((seed * 1103515245) + 12345) % 2147483648;   // Values as recommended by POSIX.1-2001 (see rand(3)).
+  return (seed / 65536); }                         // Ignore least significant 16 bits (they are less random).
+
+uint32_t load_seed() {
+// Load seed integer from seed file.
+  uint32_t seed;
+  const uint16_t nchar = 256;
+  FILE * file = fopen("seed", "r");
+  unsigned char a = fgetc(file);
+  unsigned char b = fgetc(file);
+  unsigned char c = fgetc(file);
+  unsigned char d = fgetc(file);
+  seed = (a * nchar * nchar * nchar) + (b * nchar * nchar) + (c * nchar) + d;
+  fclose(file);
+  return seed; }
+
+void save_seed(uint32_t seed) {
+// Save seed integer to seed file.
+  const uint16_t nchar = 256;
+  unsigned char a = seed / (nchar * nchar * nchar);
+  unsigned char b = (seed - (a * nchar * nchar * nchar)) / (nchar * nchar);
+  unsigned char c = (seed - ((a * nchar * nchar * nchar) + (b * nchar * nchar))) / nchar;
+  unsigned char d = seed % nchar;
+  FILE * file = fopen("seed", "w");
+  fputc(a, file);
+  fputc(b, file);
+  fputc(c, file);
+  fputc(d, file);
+  fclose(file); }
+
 void toggle_window (struct WinMeta * win_meta, struct Win * win) {
 // Toggle display of window win.
   if (0 != win->curses)
@@ -29,8 +67,9 @@ void growshrink_active_window (struct WinMeta * win_meta, char change) {
       width++;
     resize_active_window (win_meta, height, width); } }
 
-struct Map init_map () {
+struct Map init_map (uint32_t seed) {
 // Initialize map with some experimental start values.
+  rrand(1, seed);
   struct Map map;
   map.width = 96;
   map.height = 32;
@@ -42,7 +81,7 @@ struct Map init_map () {
   for (y = 0; y < map.height; y++)
     for (x = 0; x < map.width; x++) {
       terrain = '.';
-      ran = rand();
+      ran = rrand(0, 0);
       if (   0 == ran % ((x*x) / 3 + 1)
           || 0 == ran % ((y*y) / 3 + 1)
           || 0 == ran % ((map.width - x - 1) * (map.width - x - 1) / 3 + 1)
@@ -65,7 +104,7 @@ void map_scroll (struct Map * map, char dir) {
 void next_turn (struct World * world) {
 // Increment turn and move enemy.
   world->turn++;
-  char d = rand() % 5;
+  char d = rrand(0, 0) % 5;
   char ty = world->monster->y;
   char tx = world->monster->x;
   if (1 == d)
@@ -143,18 +182,28 @@ void move_player (struct World * world, char d) {
   prev = success * d;
   next_turn (world); }
 
-void player_wait(struct World * world) {
+void player_wait (struct World * world) {
 // Make player wait one turn.
   next_turn (world);
   update_log (world, "\nYou wait."); }
 
-int main () {
+int main (int argc, char *argv[]) {
+  uint32_t seed = time(NULL);
+  int opt;
+  while ((opt = getopt(argc, argv, "l")) != -1) {
+    switch (opt) {
+      case 'l':
+       seed = load_seed();
+        break;
+      default:
+        exit(EXIT_FAILURE); } }
+
   struct World world;
   init_keybindings(&world);
   world.turn = 0;
   world.log = calloc(1, sizeof(char));
   update_log (&world, "Start!");
-  struct Map map = init_map();
+  struct Map map = init_map(seed);
   world.map = &map;
   struct Player player;
   player.y = 16;
@@ -218,6 +267,8 @@ int main () {
       keyswin_move_selection (&world, 'd');
     else if (key == get_action_key(world.keybindings, "keys mod"))
       keyswin_mod_key (&world, &win_meta);
+    else if (key == get_action_key(world.keybindings, "save seed"))
+      save_seed(seed);
     else if (key == get_action_key(world.keybindings, "map up"))
       map_scroll (&map, 'n');
     else if (key == get_action_key(world.keybindings, "map down"))