diff options
Diffstat (limited to 'world.scm')
| -rw-r--r-- | world.scm | 35 |
1 files changed, 35 insertions, 0 deletions
@@ -80,4 +80,39 @@ (define (scene-find-all-tagged scene tag) (filter (lambda (e) (member tag (entity-ref e #:tags '()))) (scene-entities scene))) + + ;; First wins: one origin entity per #:group-id (for lookup). + (define (group-origin-alist entities) + (let loop ((es entities) (acc '())) + (if (null? es) + acc + (let ((e (car es))) + (if (and (entity-ref e #:group-origin? #f) + (entity-ref e #:group-id #f)) + (let ((gid (entity-ref e #:group-id))) + (if (assq gid acc) + (loop (cdr es) acc) + (loop (cdr es) (cons (cons gid e) acc)))) + (loop (cdr es) acc)))))) + + ;; Snap member #:x/#:y to origin + #:group-local-x/y. Call after moving origins (tweens, etc.). + (define (scene-sync-groups! scene) + (let* ((ents (scene-entities scene)) + (origins (group-origin-alist ents))) + (scene-entities-set! scene + (map (lambda (e) + (if (and (entity-ref e #:group-id #f) + (not (entity-ref e #:group-origin? #f))) + (let* ((gid (entity-ref e #:group-id)) + (o (assq gid origins))) + (if o + (let ((origin (cdr o))) + (entity-set (entity-set e #:x (+ (entity-ref origin #:x 0) + (entity-ref e #:group-local-x 0))) + #:y (+ (entity-ref origin #:y 0) + (entity-ref e #:group-local-y 0)))) + e)) + e)) + ents)) + scene)) ) |