Had to refactor the GameDB to use a list of levels instead of a vector of levels. If you get a _reference_ to an element of a vector, and then resize the vector, you'll get a crash if the realoc moves the data buffer. Using a list is actually what we want.

game_level.cpp

@@ -6,6 +6,7 @@
 #include "components.hpp"
 #include "rituals.hpp"
 #include "textures.hpp"
+#include <list>
 
 using lighting::LightRender;
 using std::shared_ptr, std::make_shared;
@@ -20,11 +21,11 @@ namespace GameDB {
   using std::shared_ptr, std::string, std::make_shared;
 
   struct LevelDB {
-    std::vector<GameDB::Level> levels;
+    std::list<GameDB::Level> levels;
     size_t current_level = 0;
   };
 
-  shared_ptr<LevelDB> LDB;
+  shared_ptr<LevelDB> LDB = nullptr;
   bool initialized = false;
 
   LevelScaling scale_level() {
@@ -46,8 +47,18 @@ namespace GameDB {
     return world;
   }
 
+  void register_level(Level level) {
+    // size BEFORE push to get the correct index
+    level.index = LDB->levels.size();
 
-  size_t new_level(std::shared_ptr<DinkyECS::World> prev_world) {
+    LDB->levels.push_back(level);
+
+    dbc::check(level.index == LDB->levels.size() - 1, "Level index is not the same as LDB->levels.size() - 1, off by one error");
+
+    LDB->current_level = level.index;
+  }
+
+  void new_level(std::shared_ptr<DinkyECS::World> prev_world) {
     dbc::check(initialized, "Forgot to call GameDB::init()");
     auto world = clone_load_world(prev_world);
 
@@ -59,16 +70,16 @@ namespace GameDB {
     WorldBuilder builder(*map, *collision);
     builder.generate(*world);
 
-    size_t index = LDB->levels.size();
+    auto lights = make_shared<LightRender>(map->tiles());
 
     auto player = world->get_the<Player>();
 
-    LDB->levels.emplace_back(index, player.entity, map, world,
-        make_shared<LightRender>(map->tiles()), collision);
-
-    dbc::check(index == LDB->levels.size() - 1, "Level index is not the same as LDB->levels.size() - 1, off by one error");
-
-    return index;
+    register_level({
+      .player=player.entity,
+      .map=map,
+      .world=world,
+      .lights=lights,
+      .collision=collision});
   }
 
   void init() {
@@ -89,18 +100,15 @@ namespace GameDB {
 
   Level& create_level() {
     dbc::check(initialized, "Forgot to call GameDB::init()");
-    dbc::check(LDB->current_level < LDB->levels.size(), "attempt to get next level when at end");
 
-    size_t level = new_level(current_world());
-    dbc::check(level == LDB->current_level + 1, "new level index is wrong");
+    new_level(current_world());
 
-    LDB->current_level++;
-    return LDB->levels.at(LDB->current_level);
+    return LDB->levels.back();
   }
 
   Level &current_level() {
     dbc::check(initialized, "Forgot to call GameDB::init()");
-    return LDB->levels.at(LDB->current_level);
+    return LDB->levels.back();
   }
 
   components::Position& player_position() {