Improve engine error handling, add unload call, reset atoms

src/engine.clj

@@ -18,14 +18,19 @@
       (println e))))
 
 (defn run-game!
-  [{:keys [title width height config-path init input update draw watch-fn]
+  [{:keys [title width height config-path init input update draw unload watch-fn]
     :or   {title "Untitled" width 1200 height 900 watch-fn (constantly nil)}}]
   (rl/set-trace-log-level! rl/log-warning)
   (rl/init-window! width height title)
   (rl/set-target-fps! 60)
-  (let [config (edn/read-string (slurp config-path))]
+  (let [config (if config-path
+                 (edn/read-string (slurp config-path))
+                 {})]
     (reset! game-config {:config-path config-path :config config})
+    (try
       (reset! game-state (init config))
+      (catch Throwable t
+        (println t)))
     (while (not (rl/window-should-close?))
       (if @last-error
         (Thread/sleep 50)
@@ -40,4 +45,12 @@
                 (println t)
                 (reset! last-error t)
                 (w/watch! (merge (watch-fn config @game-state) {:error t}))))))))
-    (rl/close-window!)))
+    (try
+      (when unload
+        (unload @game-state))
+      (catch Throwable t
+        (println t)))
+    (rl/close-window!)
+    (reset! last-error nil)
+    (reset! game-state nil)
+    (reset! game-config nil)))