Add key-directions and key-wasd procedures.

* 2d/game.scm (key-directions, key-wasd): New procedures.
(arrows, key-arrows): Renamed.

1 files changed, 17 insertions, 11 deletions

diff --git a/2d/game.scm b/2d/game.scm
index 1fb543a..e6c0161 100644
--- a/2d/game.scm
+++ b/2d/game.scm
@@ -43,7 +43,9 @@
             window-size
             key-last-pressed
             key-down?
-            arrows
+            key-directions
+            key-arrows
+            key-wasd
             mouse-position
             mouse-down?
             current-fps))
@@ -195,16 +197,20 @@ time in milliseconds that has passed since the last game update."
   "Return a signal for BUTTON."
   (signal-hash-ref mouse-signals button))
 
-(define arrows (signal-lift4 (lambda (up? down? left? right?)
-                               (let ((up (if up? -1 0))
-                                     (down (if down? 1 0))
-                                     (left (if left? -1 0))
-                                     (right (if right? 1 0)))
-                                 (vector2 (+ left right) (+ up down))))
-                             (key-down? 'up)
-                             (key-down? 'down)
-                             (key-down? 'left)
-                             (key-down? 'right)))
+(define (key-directions up down left right)
+  (signal-lift4 (lambda (up? down? left? right?)
+                  (let ((up (if up? -1 0))
+                        (down (if down? 1 0))
+                        (left (if left? -1 0))
+                        (right (if right? 1 0)))
+                    (vector2 (+ left right) (+ up down))))
+                (key-down? up)
+                (key-down? down)
+                (key-down? left)
+                (key-down? right)))
+
+(define key-arrows (key-directions 'up 'down 'left 'right))
+(define key-wasd (key-directions 'w 's 'a 'd))
 
 (define (handle-event e)
   "Call the relevant callbacks for the event E."