More asteroids.

diff --git a/games/asteroids/asteroids.scm b/games/asteroids/asteroids.scm
index 0ce6832165538e33c6b4392da6fafb823059c407..3b45d99f343f19f0fd26cca8ae6070e2f58ab473 100644 (file)
--- a/games/asteroids/asteroids.scm
+++ b/games/asteroids/asteroids.scm
@@ -15,17 +15,19 @@
 (define-mob (asteroid
             (image (load-texture "Asteroid.png"))
             (x 0) (y 0) (angle 0) (dir 0) (size 100))
-  (let ((r (degrees-to-radians (- dir))))
-    (set! x (+ x (sin r)))
-    (set! y (+ y (cos r))))
-  (set! angle (+ angle 1))
-
-  (cond ((or (> x max-x) (< x min-x))
-        (set! dir (* -1 dir))))
-  (cond ((or (> y max-y) (< y min-y))
-        (set! dir (- 180 dir))))
+  (cond ((asteroid-killed?)
+        (kill-me))
+       (else
+        (let ((r (degrees-to-radians (- dir))))
+          (set! x (+ x (sin r)))
+          (set! y (+ y (cos r))))
+        (set! angle (+ angle 1))
+
+        (cond ((or (> x max-x) (< x min-x))
+               (set! dir (* -1 dir))))
+        (cond ((or (> y max-y) (< y min-y))
+               (set! dir (- 180 dir))))))
   
-  (if (asteroid-killed?) (kill-me))
   (translate x y)
   (rotate angle)
   (draw-texture image))
@@ -55,15 +57,25 @@
   (rotate angle)
   (draw-texture (if moving ship2 ship1)))
 
+(define-macro (shot-killed?)
+  `(> (apply +
+            (map-mobs
+             (lambda (a) (if (< (distance-between-points (list (assoc-ref a 'x) (assoc-ref a 'y)) (list x y)) (assoc-ref a 'size)) 1 0))
+             'asteroid))
+      0))
+
 (define-mob (shot (x 0) (y 0) (angle 0))
-  (let ((r (degrees-to-radians (- angle))))
-    (set! x (+ x (* 10 (sin r))))
-    (set! y (+ y (* 10 (cos r))))
-    (cond ((or (> x max-x)
-              (< x min-x)
-              (> y max-y)
-              (< y min-y))
-          (kill-me))))
+  (cond ((shot-killed?)
+        (kill-me))
+       (else
+        (let ((r (degrees-to-radians (- angle))))
+          (set! x (+ x (* 10 (sin r))))
+          (set! y (+ y (* 10 (cos r))))
+          (cond ((or (> x max-x)
+                     (< x min-x)
+                     (> y max-y)
+                     (< y min-y))
+                 (kill-me))))))
 
   (translate x y)
   (rotate angle)