diff options
Diffstat (limited to '2d')
| -rw-r--r-- | 2d/animation.scm | 28 |
1 files changed, 13 insertions, 15 deletions
diff --git a/2d/animation.scm b/2d/animation.scm index 2c9e9f0..c1b71d7 100644 --- a/2d/animation.scm +++ b/2d/animation.scm @@ -63,33 +63,26 @@ ;; The <animator> type encapsulates the state for playing an ;; animation. (define-record-type <animator> - (%make-animator animation frame time) + (%make-animator animation frame time playing) animator? (animation animator-animation) (frame animator-frame set-animator-frame!) - (time animator-time set-animator-time!)) + (time animator-time set-animator-time!) + (playing animator-playing? set-animator-playing!)) (define (make-animator animation) "Creates a new animation state object." - (%make-animator animation 0 0)) + (%make-animator animation 0 0 #t)) (define (animator-frame-complete? state) (>= (animator-time state) (animation-frame-duration (animator-animation state)))) -(define (animator-playing? state) - "Return true if animation STATE is not done playing the -animation. This will always return #t if the animation loops." - (not (= (animator-frame state) -1))) - (define (animator-next-frame state) "Return the next frame index for the animation STATE. Return -1 when the animation is complete." - (let ((frame (1+ (animator-frame state))) - (animation (animator-animation state))) - (cond ((< frame (animation-length animation)) frame) - ((animation-loop? animation) 0) - (else -1)))) + (modulo (1+ (animator-frame state)) + (animation-length (animator-animation state)))) (define (animator-texture state) "Returns the texture for the animation at the current frame index." @@ -98,8 +91,13 @@ the animation is complete." (define (animator-next! state) "Advance to the next animation frame for the given animation STATE." - (set-animator-time! state 0) - (set-animator-frame! state (animator-next-frame state))) + (let ((next-frame (animator-next-frame state))) + (define (keep-playing?) + (or (not (= 0 next-frame)) + (animation-loop? (animator-animation state)))) + (set-animator-time! state 0) + (set-animator-frame! state next-frame) + (set-animator-playing! state (keep-playing?)))) (define (animator-update! state) "Increments the frame time for the animation STATE and advances to |