Pack and parse wall data from map files.

modules/game/actors.scm

@@ -1,5 +1,6 @@
 (define-module (game actors)
   #:use-module (goblins core)
+  #:use-module (hoot bytevectors)
   #:use-module (ice-9 match)
   #:export (^cell
             ^level))
@@ -67,7 +68,7 @@
     (('wire-state) #f)
     (('describe) '(player))))
 
-(define (^level bcom width height)
+(define (^level bcom width height objects)
   (define player (spawn ^player))
   (define player-coords (spawn ^cell))
   (define (make-grid)
@@ -176,9 +177,19 @@
   ;; TODO: actually write levels
   (warp-player 10 8)
 
-  ($ (grid-ref grid 3 7) (spawn ^exit))
+  ;; Parsed packed object data and spawn objects.
+  (let ((len (bytevector-length objects)))
+    (let lp ((i 0))
+      (when (< i len)
+        (let ((x (bytevector-u8-ref objects i))
+              (y (bytevector-u8-ref objects (+ i 1)))
+              (obj (match (bytevector-u8-ref objects (+ i 2))
+                     (1 (spawn ^wall 'brick))
+                     (id (error "invalid level object" id)))))
+          ($ (grid-ref grid x y) obj))
+        (lp (+ i 3)))))
 
-  ($ (grid-ref grid 4 4) (spawn ^wall 'brick))
+  ($ (grid-ref grid 3 7) (spawn ^exit))
 
   ($ (grid-ref grid 4 3) (spawn ^clock-emitter 3))
   ($ (grid-ref grid 5 3) (spawn ^wall 'copper))