2 files changed, 45 insertions(+), 3 deletions(-)

M fairy.lisp
M tiled.lisp

@@ 2,6 2,7 @@
   (:use :cl)
   (:export draw
            defdraw
+           update
            element
            origin
            scale


@@ 21,6 22,8 @@
 (defgeneric draw (element)
   (:documentation "Draw the element on the screen"))
 
+(defgeneric update (element dt)
+  (:documentation "Update the element after ~dt~ ms."))
 
 (defclass element ()
   ((origin :initarg :origin


@@ 33,6 36,9 @@
             :initform t
             :accessor visible)))
 
+(defmethod update ((el element) dt)
+  ())
+
 (defmacro defdraw ((el class) &rest body)
   `(defmethod draw ((,el ,class))
      (with-slots (origin scale visible) ,el


@@ 95,6 101,11 @@
             (cdr (assoc key (children el))))
         value))
 
+(defmethod update ((el layer) dt)
+  (dolist (e (children el))
+    (update (cdr e) dt))
+  (call-next-method))
+
 (defmethod delete-child ((el layer) child)
   (setf (children el) (remove child (children el) :key #'cdr)))
 

@@ 1,6 1,9 @@
 (defpackage :fairy/tiled
   (:use :cl)
-  (:export tile))
+  (:export tile
+           current
+           start-frame-animation
+           stop-frame-animation))
 
 (cl:in-package :fairy/tiled)
 


@@ 11,10 14,29 @@
             :writer (setf change-tileset))
    (current :initarg :current
             :initform 0
-            :accessor :current)
+            :accessor current)
+   (frames :initform nil
+           :accessor frames)
+   (animation-period :initform 0
+                     :accessor animation-period)
+   (animation-started-since :initform 0
+                            :accessor animation-started-since)
    (get-resource :initarg :get-resource
                  :initform 'alexandria:make-keyword
-                 :reader :get-resource)))
+                 :reader get-resource)))
+
+(defmethod start-frame-animation ((el tile) seq period)
+  (when (car seq)
+    (setf (frames el) seq)
+    (setf (animation-period el) period)
+    (setf (animation-started-since el) 0)
+    (setf (current el) (car seq))))
+
+(defmethod stop-frame-animation ((el tile) new-current)
+  (setf (frames el) nil)
+  (setf (animation-period el) 0)
+  (setf (animation-started-since el) 0)
+  (setf (current el) new-current))
 
 (defmethod initialize-instance :after ((el tile) &key)
   (let ((tileset (cl-tiled:load-tileset (tileset el))))


@@ 44,3 66,12 @@
                                                   (* line tile-height))
                             :width tile-width
                             :height tile-height))))
+
+(defmethod fairy:update ((el tile) dt)
+  (with-slots (animation-period frames animation-started-since) el
+    (when frames
+      (let* ((time (+ (animation-started-since el) dt))
+             (frame-duration (/ animation-period (length frames)))
+             (new-current (mod (truncate time frame-duration) (length frames))))
+        (setf (current el) (nth new-current frames))
+        (setf (animation-started-since el) time)))))