Added stringifying escape & F keys; add sound, sys FFI; unconflict time.h and timer.h

source/scripts/engine.scm

@@ -32,4 +32,15 @@
 (define (win_fulltoggle w) (win_cmd w 0))
 (define (win_fullscreen w) (win_cmd w 1))
 (define (win_unfullscreen w) (win_cmd w 2))
+(define (win_title s) (win_cmd 0 3 s))
 
+(define (load_level s) (gen_cmd 0 s))
+(define (load_prefab s) (gen_cmd 1 s))
+(define (quit) (sys_cmd 0))
+(define (exit) (quit))
+
+
+(define (sound_play sound) (sound_cmd sound 0))
+(define (sound_pause sound) (sound_cmd sound 1))
+(define (sound_stop sound) (sound_cmd sound 2))
+(define (sound_restart sound) (sound_cmd sound 3))