Engine: implemented "max_save" override option in config

This option is purposed to increase number of save slots available when playing older games. It affects standard save/restore dialogs filled with list of saves. It won't (and technically cannot) affect any custom made save system.

Author: ivan-mogilko

Engine/ac/game.cpp

@@ -426,11 +426,16 @@ ScriptDateTime* Game_GetSaveSlotTime(int slnum)
     return sdt;
 }
 
-void restore_game_dialog() {
+void restore_game_dialog()
+{
     restore_game_dialog2(1, LEGACY_TOP_BUILTINDIALOGSAVESLOT);
 }
 
-void restore_game_dialog2(int min_slot, int max_slot) {
+void restore_game_dialog2(int min_slot, int max_slot)
+{
+    // Optionally override the max slot
+    max_slot = usetup.max_save_slot > 0 ? usetup.max_save_slot : max_slot;
+
     can_run_delayed_command();
     if (thisroom.Options.SaveLoadDisabled == 1) {
         DisplayMessage(983);
@@ -443,7 +448,8 @@ void restore_game_dialog2(int min_slot, int max_slot) {
     do_restore_game_dialog(min_slot, max_slot);
 }
 
-bool do_restore_game_dialog(int min_slot, int max_slot) {
+bool do_restore_game_dialog(int min_slot, int max_slot)
+{
     setup_for_dialog();
     int toload = loadgamedialog(min_slot, max_slot);
     restore_after_dialog();
@@ -452,11 +458,16 @@ bool do_restore_game_dialog(int min_slot, int max_slot) {
     return toload >= 0;
 }
 
-void save_game_dialog() {
+void save_game_dialog()
+{
     save_game_dialog2(1, LEGACY_TOP_BUILTINDIALOGSAVESLOT);
 }
 
-void save_game_dialog2(int min_slot, int max_slot) {
+void save_game_dialog2(int min_slot, int max_slot)
+{
+    // Optionally override the max slot
+    max_slot = usetup.max_save_slot > 0 ? usetup.max_save_slot : max_slot;
+
     if (thisroom.Options.SaveLoadDisabled == 1) {
         DisplayMessage(983);
         return;

Engine/ac/gamesetup.h

@@ -121,6 +121,8 @@ struct GameSetup
     // is not implemented (or does not work correctly).
     int   key_save_game = 0;
     int   key_restore_game = 0;
+    // Optional override for the max save slot
+    int   max_save_slot = 0;
 
     // Accessibility settings and overrides;
     // these are meant to make playing the game easier, by modifying certain

Engine/ac/listbox.cpp

@@ -17,6 +17,7 @@
 #include <allegro.h> // find files
 #include "ac/common.h"
 #include "ac/game.h"
+#include "ac/gamesetup.h"
 #include "ac/gamesetupstruct.h"
 #include "ac/gamestate.h"
 #include "ac/global_game.h"
@@ -163,6 +164,9 @@ int ListBox_GetSaveGameSlots(GUIListBox *listbox, int index) {
 
 int ListBox_FillSaveGameList2(GUIListBox *listbox, int min_slot, int max_slot)
 {
+  // Optionally override the max slot
+  max_slot = usetup.max_save_slot > 0 ? usetup.max_save_slot : max_slot;
+
   max_slot = std::min(max_slot, TOP_SAVESLOT);
   min_slot = std::min(max_slot, std::max(0, min_slot));
 

Engine/main/config.cpp

@@ -412,6 +412,7 @@ void apply_config(const ConfigTree &cfg)
         usetup.override_upscale = CfgReadBoolInt(cfg, "override", "upscale", usetup.override_upscale);
         usetup.key_save_game = CfgReadInt(cfg, "override", "save_game_key", 0);
         usetup.key_restore_game = CfgReadInt(cfg, "override", "restore_game_key", 0);
+        usetup.max_save_slot = CfgReadInt(cfg, "override", "max_save", 0);
 
         // Accessibility settings
         usetup.access_speechskip = parse_speechskip_style(CfgReadString(cfg, "access", "speechskip"));

OPTIONS.md

@@ -128,6 +128,7 @@ Locations of two latter files differ between running platforms:
     * mac - MacOS.
   * legacysave_assume_dataver = \[integer\] - when restoring a save of a legacy format, lets engine assume certain game data version ID. This may be necessary because of a mistake in pre-3.5.0 save formats, where contents depended on a game data version rather than a save version.
   * legacysave_let_gui_diff = \[0; 1\] - when restoring a save of a legacy format, lets engine read less gui elements than are registered by the current game. This was a (possibly unintended) effect in pre-3.5.0 save format.
+  * max_save = \[integer\] - topmost save slot that may be used in a standard save/restore dialog in game. This affects only built-in dialogs and listboxes filled by FillSaveGameList() script command. This does not and cannot affect any other custom scripted save systems.
   * restore_game_key = \[integer\] - key for calling built-in restore game dialog. Key value corresponds to the [AGS script keycode](https://github.com/adventuregamestudio/ags-manual/wiki/Keycodes).
   * save_game_key = \[integer\] - key for calling built-in save game dialog.
   * upscale = \[0; 1\] - run game in the "upscale mode". The earlier versions of AGS provided support for "upscaling" low-res games to hi-res. The script API has means for detecting if the game is running upscaled, and game developer could use this opportunity to setup game accordingly (e.g. assign hi-res fonts, etc). This options works **only** for games created before AGS 3.1.0 with low-res native resolution, such as 320x200 or 320x240, and it may somewhat improve