diff options
| -rw-r--r-- | 2d/game-loop.scm | 34 |
1 files changed, 16 insertions, 18 deletions
diff --git a/2d/game-loop.scm b/2d/game-loop.scm index 8352fdd..d8554db 100644 --- a/2d/game-loop.scm +++ b/2d/game-loop.scm @@ -137,32 +137,30 @@ is the unused accumulator time." (update (- accumulator frame-interval))) accumulator)) +(define (time-left current-time next-time) + (max (floor (- next-time (SDL:get-ticks))) 0)) + ;;; ;;; Game Loop ;;; (define (run-game-loop) "Runs event handling, update, and render loop." - (define (game-loop time last-time fps-time accumulator fps) + (define (game-loop last-time next-time fps-time accumulator fps) (handle-events) - (let* ((dt (- time last-time)) + (let* ((time (SDL:get-ticks)) + (dt (- time last-time)) (accumulator (+ accumulator dt)) (current-fps-time (+ fps-time dt)) - (current-time (SDL:get-ticks))) - ;; Update and render when the accumulator reaches the threshold. - (if (>= accumulator frame-interval) - (let ((remainder (update accumulator))) - (render) - (game-loop current-time - time - (modulo current-fps-time 1000) - remainder - (increment-fps fps current-fps-time))) - (game-loop current-time - time - current-fps-time - accumulator - fps)))) + (remainder (update accumulator))) + (render) + ;; Sleep for a bit if there's time in between frames + (SDL:delay (time-left (SDL:get-ticks) next-time)) + (game-loop time + (+ next-time frame-interval) + (modulo current-fps-time 1000) + remainder + (increment-fps fps current-fps-time)))) (let ((time (SDL:get-ticks))) - (game-loop time time 0 0 0))) + (game-loop time (+ time frame-interval) 0 0 0))) |