Store cache data in a separate folder

lib/SDL3_polyfills.h

@@ -0,0 +1,49 @@
+#pragma once
+
+// Put polyfills for stuff we want to use from SDL3. Remove this when we're on SDL3.
+
+#include <SDL.h>
+#include <jni.h>
+
+const char *SDL_GetAndroidCachePath(void)
+{
+    static char *s_AndroidCachePath = NULL;
+
+    if (!s_AndroidCachePath) {
+        JNIEnv* env = (JNIEnv*)SDL_AndroidGetJNIEnv();
+        jobject activity = (jobject)SDL_AndroidGetActivity();
+
+        if (!env || !activity) {
+            SDL_Log("Failed to get JNI environment or Activity.");
+            return NULL;
+        }
+
+        // Get the getCacheDir() method
+        jclass activityClass = (*env)->GetObjectClass(env, activity);
+        jmethodID getCacheDirMethod = (*env)->GetMethodID(env, activityClass, "getCacheDir", "()Ljava/io/File;");
+
+        if (!getCacheDirMethod) {
+            SDL_Log("Failed to get getCacheDir method.");
+            return NULL;
+        }
+
+        jobject cacheDirFile = (*env)->CallObjectMethod(env, activity, getCacheDirMethod);
+        jclass fileClass = (*env)->GetObjectClass(env, cacheDirFile);
+        jmethodID getAbsolutePathMethod = (*env)->GetMethodID(env, fileClass, "getAbsolutePath", "()Ljava/lang/String;");
+
+        if (!getAbsolutePathMethod) {
+            SDL_Log("Failed to get getAbsolutePath method.");
+            return NULL;
+        }
+
+        jstring absolutePath = (jstring)(*env)->CallObjectMethod(env, cacheDirFile, getAbsolutePathMethod);
+        const char* cachePath = (*env)->GetStringUTFChars(env, absolutePath, NULL);
+
+        char* result = SDL_strdup(cachePath);
+
+        (*env)->ReleaseStringUTFChars(env, absolutePath, cachePath);
+
+        s_AndroidCachePath = result;
+    }
+    return s_AndroidCachePath;
+}

src/tms/core/storage.c

@@ -7,6 +7,10 @@
 
 #include <unistd.h>
 
+#ifdef __ANDROID__
+    #include <SDL3_polyfills.h>
+#endif
+
 #ifdef TMS_BACKEND_WINDOWS
     #include <direct.h>
     #define mkdir(dirname, ...) _mkdir(dirname)
@@ -95,7 +99,43 @@ const char *tms_storage_path(void)
 
 const char *tms_storage_cache_path(void)
 {
-    return tms_storage_path();
+#ifdef __ANDROID__
+    return SDL_GetAndroidCachePath();
+#elif defined(__EMSCRIPTEN__)
+    return SDL_GetPrefPath("Bithack", "Principia");
+#elif defined(SCREENSHOT_BUILD)
+    return "/tmp/principia_cache";
+#else
+    static char *cache_path = 0;
+
+    if (cache_path)
+        return cache_path;
+
+    char *path = (char *)malloc(1024);
+
+    if (_storage_portable) { // Portable
+        char* exedir = SDL_GetBasePath();
+        strcpy(path, exedir);
+        strcat(path, "cache");
+    } else { // System
+#ifdef TMS_BACKEND_WINDOWS
+        strcpy(path, getenv("LOCALAPPDATA"));
+        strcat(path, "\\Principia");
+#else
+        const char* xdg_cache_home = getenv("XDG_CACHE_HOME");
+        if (!xdg_cache_home) {
+            strcpy(path, getenv("HOME"));
+            strcat(path, "/.cache/principia");
+        } else {
+            strcpy(path, xdg_cache_home);
+            strcat(path, "/principia");
+        }
+#endif
+    }
+
+    cache_path = path;
+    return cache_path;
+#endif
 }
 
 void tms_storage_create_dirs(void)