1 files changed, 14 insertions, 27 deletions

diff --git a/composeApp/src/commonMain/kotlin/coffee/liz/ecs/animation/AnimationSystem.kt b/composeApp/src/commonMain/kotlin/coffee/liz/ecs/animation/AnimationSystem.kt
index 7ae405e..7968250 100644
--- a/composeApp/src/commonMain/kotlin/coffee/liz/ecs/animation/AnimationSystem.kt
+++ b/composeApp/src/commonMain/kotlin/coffee/liz/ecs/animation/AnimationSystem.kt
@@ -1,35 +1,27 @@
 package coffee.liz.ecs.animation
 
-import coffee.liz.ecs.System
+import coffee.liz.ecs.TickedSystem
 import coffee.liz.ecs.World
+import kotlin.time.Duration
 
 /**
- * System that updates animation playback state for all entities with an Animator component.
- *
- * This system:
- * - Updates elapsed time for playing animations
- * - Advances frame indices based on frame duration
- * - Handles loop modes (ONCE, LOOP, PING_PONG)
- * - Stops animations when they complete (for ONCE mode)
+ * Updates animation playback state for all [Animator] components in [World].
  */
-class AnimationSystem : System {
-    override fun update(world: World, deltaTime: Float) {
-        // Query all entities that have both Animator and SpriteSheet
-        world.query(Animator::class, SpriteSheet::class).forEach { entity ->
-            val animator = entity.get(Animator::class) ?: return@forEach
-
-            // Skip if animation is not playing
+class AnimationSystem(animationTickRate: Duration) : TickedSystem(animationTickRate) {
+    override fun update(world: World, ticks: Int) {
+        world.query(Animator::class).forEach { entity ->
+            val animator = entity.get(Animator::class)
             if (!animator.playing) return@forEach
 
             // Get the current animation clip
             val clip = animator.clips[animator.currentClip] ?: return@forEach
 
             // Accumulate elapsed time
-            animator.elapsed += deltaTime
+            animator.elapsedTicks += ticks
 
             // Advance frames while we have enough elapsed time
-            while (animator.elapsed >= clip.frameDuration) {
-                animator.elapsed -= clip.frameDuration
+            while (animator.elapsedTicks >= clip.frameTicks) {
+                animator.elapsedTicks -= clip.frameTicks
                 advanceFrame(animator, clip)
             }
         }
@@ -39,11 +31,10 @@ class AnimationSystem : System {
      * Advances the animation to the next frame based on loop mode.
      */
     private fun advanceFrame(animator: Animator, clip: AnimationClip) {
-        animator.frameIndex += animator.direction
+        animator.frameIndex += animator.direction.step
 
         when (clip.loopMode) {
             LoopMode.ONCE -> {
-                // Play once and stop on last frame
                 if (animator.frameIndex >= clip.frameNames.size) {
                     animator.frameIndex = clip.frameNames.size - 1
                     animator.playing = false
@@ -51,25 +42,21 @@ class AnimationSystem : System {
             }
 
             LoopMode.LOOP -> {
-                // Loop back to beginning
                 if (animator.frameIndex >= clip.frameNames.size) {
                     animator.frameIndex = 0
                 } else if (animator.frameIndex < 0) {
-                    // Handle negative wrap (shouldn't happen in LOOP but be safe)
                     animator.frameIndex = clip.frameNames.size - 1
                 }
             }
 
             LoopMode.PING_PONG -> {
-                // Bounce back and forth
+                // Go to (endFrame - 1) or (beginFrame + 1) ping ponging
                 if (animator.frameIndex >= clip.frameNames.size) {
-                    // Hit the end, reverse direction
                     animator.frameIndex = (clip.frameNames.size - 2).coerceAtLeast(0)
-                    animator.direction = -1
+                    animator.direction = AnimationDirection.BACKWARD
                 } else if (animator.frameIndex < 0) {
-                    // Hit the beginning, reverse direction
                     animator.frameIndex = 1.coerceAtMost(clip.frameNames.size - 1)
-                    animator.direction = 1
+                    animator.direction = AnimationDirection.FORWARD
                 }
             }
         }