[example] including rotation in collision handling

1 files changed, 9 insertions, 6 deletions

diff --git a/examples/09-ghoulspree.lisp b/examples/09-ghoulspree.lisp
index d0e5ca1..ffeb324 100644
--- a/examples/09-ghoulspree.lisp
+++ b/examples/09-ghoulspree.lisp
@@ -40,7 +40,7 @@
   (with-accessors ((dr dr) (dx dx) (dy dy) (x ww::x) (y ww::y) (r ww::rotation)) thing
     (incf x dx)
     (incf y dy)
-    (incf r dr))) ;; rotation diminishes every round, just aesthetic.
+    (incf r dr))) 
 
 (defun clamp (lo val hi)
   "Returns VAL if (< LO VAL HI), otherwise returns LO or HI depending
@@ -58,14 +58,17 @@ on which boundary VAL is outside of."
       (loop for ,b in ,more-a do (progn ,@body)) )))
 
 (defun handle-collision (g1 g2 &optional (friction 0.99))
-  (with-slots ((dx1 dx) (dy1 dy)) g1
-    (with-slots ((dx2 dx) (dy2 dy)) g2
+  (with-slots ((dx1 dx) (dy1 dy) (dr1 dr)) g1
+    (with-slots ((dx2 dx) (dy2 dy) (dr2 dr)) g2
       (let ((tdx (* friction dx1))
-            (tdy (* friction dy1)))
+            (tdy (* friction dy1))
+            (tdr (* friction dr1)))
         (setf dx1 (* friction dx2)
               dy1 (* friction dy2)
+              dr1 (* friction dr2)
               dx2 tdx
-              dy2 tdy)))))
+              dy2 tdy
+              dr2 tdr)))))
 
 (ww:defhandler moveghouls
     (ww:on-perframe (app)
@@ -74,7 +77,7 @@ on which boundary VAL is outside of."
         (with-pairs
             (g1 g2) (ww:container-units app)
             (when (ww:units-intersect-p g1 g2)
-              (handle-collision g1 g2 0.99)
+              (handle-collision g1 g2 1.0)
               ;; need a "bounce" 
               (advance-pos g1)
               (advance-pos g1)