Introduced data cache for faster loading

CHANGELOG.txt

@@ -1,3 +1,8 @@
+Version 0.6.2
+- Data for cia version can be loaded from /3ds/lemmings now
+- Introduced cache to reduce start-up time
+- Bugfix
+
 Version 0.6.1
 - Bugfixes (note: multiplayer mode is not compatible with v0.6)
 

Makefile

@@ -34,7 +34,7 @@ RUN_FLAGS :=
 
 VERSION_MAJOR := 0
 VERSION_MINOR := 6
-VERSION_MICRO := 1
+VERSION_MICRO := 2
 
 # 3DS CONFIGURATION #
 

README.md

@@ -8,14 +8,16 @@ To avoid duplicates, you may only fill these folders if you own all Lemmings gam
 orig, ohno, xmas91, xmas92, holi94
 For multiplayer mode, fill the subfolders of /lemmings/2p of the host system.
 
+If you modify level files later, you should delete the CACHE_xx.DAT files in the lemmings folder afterwards.
+
 The game uses the NDSP service to play audio. Thus you need a DSP firm dump to have audio.
 You may want to use your own sound and/or music files.
 Put your wave files into lemmings/audio folder.
 See README.txt in that folder for more details.
 
-\* See README.txt in these folders.
-
 These files are not included (and will never be included),
 because they are protected by copyright law.
 
 For game control, see CONTROL.txt.
+
+\* See README.txt in these folders.

include/data_cache.h

@@ -0,0 +1,9 @@
+#ifndef DAtA_CACHE_H
+#define DAtA_CACHE_H
+#define CACHE_FILE_VERSION 0
+#include <3ds.h>
+
+void update_data_cache(u8 game, u8 multiplayer, const char* level_names);
+u8 read_data_cache(u8 game, u8 multiplayer, char* level_names);
+
+#endif

src/data_cache.c

@@ -0,0 +1,57 @@
+#include <stdio.h>
+#include "data_cache.h"
+#include "gamespecific.h"
+#include "settings.h"
+
+void update_data_cache(u8 game, u8 multiplayer, const char* level_names) {
+	u8 version = CACHE_FILE_VERSION;
+	char cachefilename[64];
+	u16 num_of_levels = 0;
+	if (!level_names) {
+		return;
+	}
+	if (!multiplayer) {
+		num_of_levels = (u16)import[game].num_of_difficulties
+				* (u16)import[game].num_of_level_per_difficulty;
+	}else{
+		return;
+	}
+	sprintf(cachefilename, "%s/CACHE_%02X.DAT",PATH_ROOT, game + (multiplayer?0x80:0));
+	FILE* cachefile = fopen(cachefilename, "wb");
+	if (!cachefile) {
+		return;
+	}
+	fwrite(&version, 1, 1, cachefile);
+	fwrite(level_names, 1, 33*num_of_levels, cachefile);
+	fclose(cachefile);
+}
+
+u8 read_data_cache(u8 game, u8 multiplayer, char* level_names) {
+	u8 version = 0;
+	char cachefilename[64];
+	u16 num_of_levels = 0;
+	if (!level_names) {
+		return 0;
+	}
+	if (!multiplayer) {
+		num_of_levels = (u16)import[game].num_of_difficulties
+				* (u16)import[game].num_of_level_per_difficulty;
+	}else{
+		return 0;
+	}
+	sprintf(cachefilename, "%s/CACHE_%02X.DAT",PATH_ROOT, game + (multiplayer?0x80:0));
+	FILE* cachefile = fopen(cachefilename, "rb");
+	if (!cachefile) {
+		return 0;
+	}
+	fread(&version, 1, 1, cachefile);
+	if (version > CACHE_FILE_VERSION) {
+		return 0;
+	}
+	u16 size = fread(level_names, 1, 33*num_of_levels, cachefile);
+	fclose(cachefile);
+	if (size != 33*num_of_levels) {
+		return 0;
+	}
+	return 1;
+}

src/main.c

@@ -22,6 +22,7 @@
 #include "main.h"
 #include "settings_menu.h"
 #include "network_menu.h"
+#include "data_cache.h"
 
 const char* LEMMINGS_DIRS[] = {"/lemmings", "/3ds/lemmings", 0};
 const char* PATH_ROOT = 0;
@@ -160,7 +161,13 @@ int main() {
 	}
 	u16 offset = 0;
 	for (i=0;i<LEMMING_GAMES;i++) {
-		games[i] = read_level_names(i, level_names + offset);
+		games[i] = read_data_cache(i, 0, level_names + offset);
+		if (!games[i]) {
+			games[i] = read_level_names(i, level_names + offset);
+			if (games[i]) {
+				update_data_cache(i, 0, level_names + offset);
+			}
+		}
 		offset += 33*
 				(u16)import[i].num_of_difficulties *
 				(u16)import[i].num_of_level_per_difficulty;
@@ -240,12 +247,18 @@ int main() {
 	if (num_2p_level[0] || num_2p_level[1]) {
 		name_2p_level = (char*)malloc(33*(u16)(num_2p_level[0]+num_2p_level[1]));
 		if (name_2p_level[0]) {
-			if (!read_level_names_from_path(import_2p[0].level_path, &num_2p_level[0], name_2p_level)) {
+			if (!read_level_names_from_path(
+					import_2p[0].level_path,
+					&num_2p_level[0],
+					name_2p_level)) {
 				name_2p_level[0] = 0;
 			}
 		}
 		if (name_2p_level[1]) {
-			if (!read_level_names_from_path(import_2p[1].level_path, &num_2p_level[1], &name_2p_level[33*(u16)num_2p_level[0]])) {
+			if (!read_level_names_from_path(
+					import_2p[1].level_path,
+					&num_2p_level[1],
+					&name_2p_level[33*(u16)num_2p_level[0]])) {
 				name_2p_level[1] = 0;
 			}
 		}