1 files changed, 114 insertions, 0 deletions
diff --git a/composeApp/src/commonMain/kotlin/coffee/liz/ecs/animation/AnimationComponents.kt b/composeApp/src/commonMain/kotlin/coffee/liz/ecs/animation/AnimationComponents.kt
new file mode 100644
index 0000000..4289eec
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+++ b/composeApp/src/commonMain/kotlin/coffee/liz/ecs/animation/AnimationComponents.kt
@@ -0,0 +1,114 @@
+package coffee.liz.ecs.animation
+
+import coffee.liz.ecs.Component
+import kotlin.jvm.JvmInline
+
+/**
+ * Loop modes for animation playback.
+ */
+enum class LoopMode {
+    /** Play once and stop on last frame */
+    ONCE,
+    /** Repeat from beginning */
+    LOOP,
+    /** Play forward, then backward, repeat */
+    PING_PONG
+}
+
+/**
+ * Type-safe wrapper for animation names.
+ */
+@JvmInline
+value class AnimationName(val value: String)
+
+/**
+ * Type-safe wrapper for frame names.
+ */
+@JvmInline
+value class FrameName(val value: String)
+
+/**
+ * Represents a rectangle region in a sprite sheet.
+ */
+data class Rect(
+    val x: Int,
+    val y: Int,
+    val width: Int,
+    val height: Int
+)
+
+/**
+ * Defines a single animation clip with frames and playback settings.
+ */
+data class AnimationClip(
+    val frameNames: List<FrameName>,
+    val frameDuration: Float,  // seconds per frame
+    val loopMode: LoopMode = LoopMode.LOOP
+)
+
+/**
+ * Component containing sprite sheet data - the image and frame definitions.
+ * This is immutable data that can be shared across entities.
+ */
+data class SpriteSheet(
+    val imagePath: String,
+    val frames: Map<FrameName, Rect>
+) : Component
+
+/**
+ * Component for animation playback state.
+ * Contains animation clips and current playback state.
+ */
+data class Animator(
+    val clips: Map<AnimationName, AnimationClip>,
+    var currentClip: AnimationName,
+    var frameIndex: Int = 0,
+    var elapsed: Float = 0f,
+    var playing: Boolean = true,
+    var direction: Int = 1  // 1 for forward, -1 for backward (used in PING_PONG)
+) : Component {
+
+    /**
+     * Play a specific animation clip by name.
+     * Resets playback state when switching clips.
+     */
+    fun play(clipName: AnimationName, restart: Boolean = true) {
+        if (currentClip != clipName || restart) {
+            currentClip = clipName
+            frameIndex = 0
+            elapsed = 0f
+            direction = 1
+            playing = true
+        }
+    }
+
+    /**
+     * Pause the current animation.
+     */
+    fun pause() {
+        playing = false
+    }
+
+    /**
+     * Resume the current animation.
+     */
+    fun resume() {
+        playing = true
+    }
+
+    /**
+     * Get the current frame name being displayed.
+     */
+    fun getCurrentFrameName(): FrameName? {
+        val clip = clips[currentClip] ?: return null
+        return clip.frameNames.getOrNull(frameIndex)
+    }
+}
+
+/**
+ * Component for entity position in 2D space.
+ */
+data class Position(
+    var x: Float,
+    var y: Float
+) : Component