FF8: Allow to customize card names via an msd direct file (#739)

Changelog.md

@@ -6,6 +6,7 @@
 
 - Ambient: Fix missing Battle ID for battles triggered using field opcodes
 - Ambient: Fix Battle ID detection for random encounters in Field
+- Modding: Allow modding card names hardcoded in exe ( https://github.com/julianxhokaxhiu/FFNx/pull/739 )
 
 # 1.20.3
 

src/exe_data.cpp

@@ -26,13 +26,24 @@
 #include "saveload.h"
 
 uint8_t *ff8_exe_scan_texts = nullptr;
+uint8_t *ff8_exe_card_names = nullptr;
+
+bool ff8_get_exe_path(const char *name, char *target_filename)
+{
+    snprintf(target_filename, MAX_PATH, "%s/exe/%s.msd", direct_mode_path.c_str(), name);
+    normalize_path(target_filename);
+
+    return fileExists(target_filename);
+}
 
 bool ff8_get_battle_scan_texts_filename(char *filename)
 {
-    snprintf(filename, MAX_PATH, "%s/exe/battle_scans.msd", direct_mode_path.c_str());
-    normalize_path(filename);
+    return ff8_get_exe_path("battle_scans", filename);
+}
 
-    return fileExists(filename);
+bool ff8_get_card_names_filename(char *filename)
+{
+    return ff8_get_exe_path("card_names", filename);
 }
 
 void ff8_dump_battle_scan_texts()
@@ -76,19 +87,49 @@ void ff8_dump_battle_scan_texts()
     fclose(f);
 }
 
-uint8_t *ff8_override_battle_scans()
+void ff8_dump_card_names()
 {
-    if (ff8_exe_scan_texts != nullptr) {
-        return ff8_exe_scan_texts;
+    uint8_t *data = *(uint8_t **)ff8_externals.card_name_positions;
+    uint16_t *positions = *(uint16_t **)ff8_externals.card_name_positions;
+    constexpr int text_count = 110;
+    uint16_t old_data_offset = (1 + text_count) * sizeof(uint16_t), new_data_offset = text_count * sizeof(uint32_t);
+    uint32_t offsets_rel_to_start[text_count] = {};
+    int higher_offset = 0;
+
+    for (int i = 0; i < text_count; ++i) {
+        offsets_rel_to_start[i] = positions[i + 1] - old_data_offset + new_data_offset;
+        if (positions[i + 1] > higher_offset) {
+            higher_offset = positions[i + 1];
+        }
+    }
+
+    for (int i = higher_offset; i < higher_offset + 1024; ++i) {
+        if (data[i] == '\0') {
+            higher_offset = i + 1;
+            break;
+        }
     }
 
     char filename[MAX_PATH] = {};
-    if (! ff8_get_battle_scan_texts_filename(filename)) {
-        if (trace_all || trace_direct) ffnx_warning("Direct file not found %s\n", filename);
+    if (ff8_get_card_names_filename(filename)) {
+        ffnx_warning("Save exe file skipped because the file [ %s ] already exists.\n", filename);
 
-        return nullptr;
+        return;
     }
 
+    FILE *f = fopen(filename, "wb");
+
+    if (f == nullptr) {
+        return;
+    }
+
+    fwrite(offsets_rel_to_start, new_data_offset, 1, f);
+    fwrite(data + old_data_offset, higher_offset - old_data_offset, 1, f);
+    fclose(f);
+}
+
+uint8_t *ff8_open_msd(char *filename)
+{
     if (trace_all || trace_direct) ffnx_info("Direct file using %s\n", filename);
 
     FILE *f = fopen(filename, "rb");
@@ -101,18 +142,54 @@ uint8_t *ff8_override_battle_scans()
     long file_size = ftell(f);
     fseek(f, 0, SEEK_SET);
 
-    ff8_exe_scan_texts = (uint8_t *)driver_malloc(file_size); // Allocated once, never freed
+    uint8_t *target_data = (uint8_t *)driver_malloc(file_size); // Allocated once, never freed
 
-    if (ff8_exe_scan_texts == nullptr) {
+    if (target_data == nullptr) {
         return nullptr;
     }
 
-    fread(ff8_exe_scan_texts, file_size, 1, f);
+    fread(target_data, file_size, 1, f);
     fclose(f);
 
+    return target_data;
+}
+
+uint8_t *ff8_override_battle_scans()
+{
+    if (ff8_exe_scan_texts != nullptr) {
+        return ff8_exe_scan_texts;
+    }
+
+    char filename[MAX_PATH] = {};
+    if (! ff8_get_battle_scan_texts_filename(filename)) {
+        if (trace_all || trace_direct) ffnx_warning("Direct file not found %s\n", filename);
+
+        return nullptr;
+    }
+
+    ff8_exe_scan_texts = ff8_open_msd(filename);
+
     return ff8_exe_scan_texts;
 }
 
+uint8_t *ff8_override_card_names()
+{
+    if (ff8_exe_card_names != nullptr) {
+        return ff8_exe_card_names;
+    }
+
+    char filename[MAX_PATH] = {};
+    if (! ff8_get_card_names_filename(filename)) {
+        if (trace_all || trace_direct) ffnx_warning("Direct file not found %s\n", filename);
+
+        return nullptr;
+    }
+
+    ff8_exe_card_names = ff8_open_msd(filename);
+
+    return ff8_exe_card_names;
+}
+
 uint8_t *ff8_battle_get_scan_text(uint8_t target_id)
 {
     uint8_t *direct_data_msd = ff8_override_battle_scans();
@@ -129,6 +206,26 @@ uint8_t *ff8_battle_get_scan_text(uint8_t target_id)
     return ((uint8_t*(*)(uint8_t))ff8_externals.scan_get_text_sub_B687C0)(target_id);
 }
 
+char *ff8_get_card_name(int32_t card_id)
+{
+    if (card_id >= 110) {
+        return nullptr;
+    }
+
+    uint8_t *direct_data_msd = ff8_override_card_names();
+    if (direct_data_msd != nullptr) {
+        uint32_t *positions = (uint32_t *)direct_data_msd;
+
+        if (trace_all) ffnx_trace("%s: get card name card_id=%d\n", __func__, card_id);
+
+        return (char *)direct_data_msd + positions[card_id];
+    }
+
+    uint16_t *positions = *(uint16_t **)ff8_externals.card_name_positions;
+
+    return *(char **)ff8_externals.card_name_positions + positions[card_id + 1];
+}
+
 void dump_exe_data()
 {
     char dirname[MAX_PATH] = {};
@@ -140,6 +237,7 @@ void dump_exe_data()
     if (ff8)
     {
         ff8_dump_battle_scan_texts();
+        ff8_dump_card_names();
     }
 }
 
@@ -153,5 +251,6 @@ void exe_data_init()
     if (ff8)
     {
         replace_call(ff8_externals.sub_84F8D0 + 0x88, ff8_battle_get_scan_text);
+        replace_function(ff8_externals.get_card_name, ff8_get_card_name);
     }
 }

src/ff8.h

@@ -1117,6 +1117,9 @@ struct ff8_externals
 	uint32_t sub_4B3140;
 	uint32_t sub_4BDB30;
 	ff8_menu_callback *menu_callbacks;
+	uint32_t menu_cards_render;
+	uint32_t sub_4EFC00;
+	uint32_t sub_4EFCD0;
 	uint32_t menu_config_controller;
 	uint32_t menu_config_render;
 	uint32_t menu_config_render_submenu;
@@ -1517,6 +1520,8 @@ struct ff8_externals
 	double *time_volume_change_related_1A78BE0;
 	uint32_t* game_mode_obj_1D9CF88;
 	uint32_t field_vars_stack_1CFE9B8;
+	uint32_t get_card_name;
+	uint32_t card_name_positions;
 };
 
 void ff8gl_field_78(struct ff8_polygon_set *polygon_set, struct ff8_game_obj *game_object);

src/ff8_data.cpp

@@ -404,6 +404,9 @@ void ff8_find_externals()
 	ff8_externals.sub_4B3140 = get_relative_call(ff8_externals.sub_4B3310, 0xC8);
 	ff8_externals.sub_4BDB30 = get_relative_call(ff8_externals.sub_4B3140, 0x4);
 	ff8_externals.menu_callbacks = (ff8_menu_callback *)get_absolute_value(ff8_externals.sub_4BDB30, 0x11);
+	ff8_externals.menu_cards_render = get_absolute_value(uint32_t(ff8_externals.menu_callbacks[7].func), 0x5);
+	ff8_externals.sub_4EFC00 = get_relative_call(ff8_externals.menu_cards_render, 0x2B6);
+	ff8_externals.sub_4EFCD0 = get_absolute_value(ff8_externals.sub_4EFC00, 0xB0);
 	ff8_externals.menu_config_render = get_absolute_value(uint32_t(ff8_externals.menu_callbacks[8].func), 0x3);
 	ff8_externals.menu_config_render_submenu = get_relative_call(ff8_externals.menu_config_render, 0x101);
 	ff8_externals.menu_config_controller = get_absolute_value(uint32_t(ff8_externals.menu_callbacks[8].func), 0x8);
@@ -826,6 +829,8 @@ void ff8_find_externals()
 	ff8_externals.battle_entities_1D27BCB = get_absolute_value(ff8_externals.scan_get_text_sub_B687C0, 0x18);
 	ff8_externals.scan_text_positions = get_absolute_value(ff8_externals.scan_get_text_sub_B687C0, 0x20);
 	ff8_externals.scan_text_data = get_absolute_value(ff8_externals.scan_get_text_sub_B687C0, 0x27);
+	ff8_externals.get_card_name = get_relative_call(ff8_externals.sub_4EFCD0, 0x89);
+	ff8_externals.card_name_positions = get_absolute_value(ff8_externals.get_card_name, 0xB);
 
 	ff8_externals.fps_limiter = get_relative_call(ff8_externals.field_main_loop, 0x261);
 	if (JP_VERSION)