diff options
Diffstat (limited to '2d/game-loop.scm')
| -rw-r--r-- | 2d/game-loop.scm | 35 |
1 files changed, 28 insertions, 7 deletions
diff --git a/2d/game-loop.scm b/2d/game-loop.scm index 0337db0..168f6f7 100644 --- a/2d/game-loop.scm +++ b/2d/game-loop.scm @@ -39,7 +39,11 @@ replace-scene pop-scene run-game - quit-game-loop!)) + quit-game + pause-game + resume-game + game-running? + game-paused?)) ;;; ;;; Constants @@ -53,7 +57,6 @@ ;;; (define game-fps 0) -(define running #f) ;;; ;;; Event Handling @@ -206,7 +209,7 @@ INPUT, OUTPUT, and ERROR ports." "Exit the current scene and resume the previous scene. If there is no previous scene, the game loop will terminate." (if (null? scenes) - (quit-game-loop!) + (quit-game) (begin (set! next-scene (car scenes)) (set! scenes (cdr scenes))))) @@ -231,11 +234,14 @@ the stack." ;;; Game Loop ;;; +(define running? #f) +(define paused? #f) + (define (game-loop last-time accumulator) "Update game state, and render. LAST-TIME is the time in milliseconds of the last iteration of the loop. ACCUMULATOR is the time in milliseconds that has passed since the last game update." - (when running + (when running? (let* ((current-time (SDL:get-ticks)) (dt (- current-time last-time)) (remainder (update (+ accumulator dt)))) @@ -250,12 +256,27 @@ time in milliseconds that has passed since the last game update." (open-window (game-title game) (game-resolution game) (game-fullscreen? game)) - (set! running #t) + (set! running? #t) + (resume-game) (set-initial-scene ((game-first-scene game))) (spawn-server) (game-loop (SDL:get-ticks) 0) (close-window)) -(define (quit-game-loop!) +(define (game-running?) + (running?)) + +(define (game-paused?) + (paused?)) + +(define (pause-game) + "Pauses the game loop. Useful when developing." + (set! paused? #t)) + +(define (resume-game) + "Resumes the game loop." + (set! paused? #f)) + +(define (quit-game) "Finish the current frame and terminate the game loop." - (set! running #f)) + (set! running? #f)) |