now has separation between compiled and interpreted contexts

- use cond-expand to load raylib if the snek.scm is interpreted
- .gambini added to automatically add gambit-raylib to search order
- game now starts in background when interpreted
  - this makes it easier to incrementally develop in emacs
- game starts in foreground when compiled

1 files changed, 30 insertions, 9 deletions

diff --git a/snek.scm b/snek.scm
index d92d43f..c748c5d 100644
--- a/snek.scm
+++ b/snek.scm
@@ -1,3 +1,9 @@
+(cond-expand ((and (compilation-target (_))
+				   (not raylib))
+			  (import (raylib))
+			  (define-cond-expand-feature raylib))
+			 (else #t))
+
 (define-syntax with-drawing
   (syntax-rules ()
     ((with-drawing body ...)
@@ -9,6 +15,7 @@
 (define BLACK (raylib#make-color 0 0 0 255))
 (define WHITE (raylib#make-color 255 255 255 255))
 (define RED   (raylib#make-color 255 0 0 255))
+(define GREEN (raylib#make-color 0 255 0 255))
 
 (define KEY_ESC 256)
 (define KEY_RIGHT 262)
@@ -152,15 +159,29 @@
 			  0
 			  'right))
 
+(define (run-game)
+  (dynamic-wind
+	(lambda () (begin
+				 (raylib#set-target-fps 60)
+				 (raylib#init-window VP_WIDTH VP_HEIGHT "snek")
+				 (raylib#set-exit-key KEY_ESC)
+				 (set! game-running #t)
+				 (display "GAME ON!")))
+	(lambda () (let ((state (init)))
+				 (place-apple! state)
+				 (main-loop state)))
+	(lambda () (raylib#close-window))))
+
+(define (run-game-bg)
+  (thread-start! (make-thread (lambda () (run-game)) "game-loop")))
+
 (define (main arg)
-  (raylib#set-target-fps 60)
-  (raylib#init-window VP_WIDTH VP_HEIGHT "snek")
-  (raylib#set-exit-key KEY_ESC)
-  (set! game-running #t)
-  (display "GAME ON!")
-  (let ((state (init)))
-	(place-apple! state)
-	(main-loop state))
-  (raylib#close-window))
+  ;; compilation-target (_) denotes the interpreter !
+  (cond-expand ((compilation-target (_))
+				(display "BG-RUN")
+				(run-game-bg))
+			   (else
+				(display "FG-RUN")
+				(run-game))))
 
 (main '())