entity animation version demo

CLAUDE.md

@@ -639,10 +639,10 @@ build/
 
 ## Important Notes
 
-- The project uses SFML for graphics/audio and libtcod for roguelike utilities
+- The project uses SFML for graphics/audio (or SDL2 when building for wasm) and libtcod for roguelike utilities
 - Python scripts are loaded at runtime from the `scripts/` directory
 - Asset loading expects specific paths relative to the executable
-- The game was created for 7DRL 2025 as "Crypt of Sokoban"
+- The game was created for 7DRL 2023
 - Iterator implementations require careful handling of C++/Python boundaries
 
 ## Testing Guidelines

shade_sprite/demo.py

@@ -11,6 +11,7 @@ Scenes:
   5 - Layer Compositing: demonstrates CharacterAssembler layered texture building
   6 - Equipment Customizer: procedural + user-driven layer coloring for gear
   7 - Asset Inventory: browse discovered layer categories and files
+  8 - Entity Animation: engine-native Entity.animate() with loop - all formats
 
 Controls shown on-screen per scene.
 """
@@ -90,7 +91,7 @@ if __name__ == "__main__":
         sys.path.insert(0, parent_dir)
 
 from shade_sprite import (
-    AnimatedSprite, Direction, PUNY_24, SLIME,
+    AnimatedSprite, Direction, PUNY_24, PUNY_29, SLIME, CREATURE_RPGMAKER,
     CharacterAssembler,
     AssetLibrary, FactionGenerator,
 )
@@ -130,7 +131,7 @@ def _no_assets_fallback(scene, scene_name):
         pos=(20, 60), fill_color=WARN_COLOR)
     ui.append(msg)
     controls = mcrfpy.Caption(
-        text="[1-7] Switch scenes",
+        text="[1-8] Switch scenes",
         pos=(20, 740), fill_color=DIM_COLOR)
     ui.append(controls)
 
@@ -152,6 +153,7 @@ def _handle_scene_switch(key):
         mcrfpy.Key.NUM_5: "layers",
         mcrfpy.Key.NUM_6: "equip",
         mcrfpy.Key.NUM_7: "inventory",
+        mcrfpy.Key.NUM_8: "entity_anim",
     }
     name = scene_map.get(key)
     if name:
@@ -267,7 +269,7 @@ def _build_scene_viewer():
     ui.append(anim_ref)
 
     controls = mcrfpy.Caption(
-        text="[Q/E] Sheet  [A/D] Animation  [W/S] Direction  [1-7] Scenes",
+        text="[Q/E] Sheet  [A/D] Animation  [W/S] Direction  [1-8] Scenes",
         pos=(20, 740), fill_color=DIM_COLOR)
     ui.append(controls)
 
@@ -415,7 +417,7 @@ def _build_scene_hsl():
     ui.append(explain2)
 
     controls = mcrfpy.Caption(
-        text="[Left/Right] Hue +/-30  [Up/Down] Sat +/-0.1  [Z/X] Lit +/-0.1  [Q/E] Sheet  [1-7] Scenes",
+        text="[Left/Right] Hue +/-30  [Up/Down] Sat +/-0.1  [Z/X] Lit +/-0.1  [Q/E] Sheet  [1-8] Scenes",
         pos=(20, 740), fill_color=DIM_COLOR)
     ui.append(controls)
 
@@ -547,7 +549,7 @@ def _build_scene_gallery():
     ui.append(dir_info)
 
     controls = mcrfpy.Caption(
-        text="[W/S] Direction  [A/D] Animation  [1-7] Scenes",
+        text="[W/S] Direction  [A/D] Animation  [1-8] Scenes",
         pos=(20, 740), fill_color=DIM_COLOR)
     ui.append(controls)
 
@@ -659,7 +661,7 @@ def _build_scene_factions():
     _populate()
 
     controls = mcrfpy.Caption(
-        text="[Space] Re-roll factions  [1-7] Scenes",
+        text="[Space] Re-roll factions  [1-8] Scenes",
         pos=(20, 740), fill_color=DIM_COLOR)
     ui.append(controls)
 
@@ -840,7 +842,7 @@ def _build_scene_layers():
     ui.append(code_lbl4)
 
     controls = mcrfpy.Caption(
-        text="[Q/E] Overlay sheet  [Left/Right] Overlay hue +/-30  [1-7] Scenes",
+        text="[Q/E] Overlay sheet  [Left/Right] Overlay hue +/-30  [1-8] Scenes",
         pos=(20, 740), fill_color=DIM_COLOR)
     ui.append(controls)
 
@@ -1062,7 +1064,7 @@ def _build_scene_equip():
     _generate_variants()
 
     controls = mcrfpy.Caption(
-        text="[Tab] Slot  [Q/E] Sheet  [Left/Right] Hue  [Up/Down] Sat  [Z/X] Lit  [T] Toggle  [R] Randomize  [1-7] Scenes",
+        text="[Tab] Slot  [Q/E] Sheet  [Left/Right] Hue  [Up/Down] Sat  [Z/X] Lit  [T] Toggle  [R] Randomize  [1-8] Scenes",
         pos=(20, 740), fill_color=DIM_COLOR)
     ui.append(controls)
 
@@ -1148,7 +1150,7 @@ def _build_scene_inventory():
             text="The AssetLibrary scans the 'Individual Spritesheets' directory.",
             pos=(20, 90), fill_color=DIM_COLOR)
         ui.append(msg2)
-        controls = mcrfpy.Caption(text="[1-7] Switch scenes",
+        controls = mcrfpy.Caption(text="[1-8] Switch scenes",
                                   pos=(20, 740), fill_color=DIM_COLOR)
         ui.append(controls)
 
@@ -1275,7 +1277,7 @@ def _build_scene_inventory():
     _refresh()
 
     controls = mcrfpy.Caption(
-        text="[W/S] Category  [A/D] Subcategory  [PgUp/PgDn] Scroll files  [1-7] Scenes",
+        text="[W/S] Category  [A/D] Subcategory  [PgUp/PgDn] Scroll files  [1-8] Scenes",
         pos=(20, 740), fill_color=DIM_COLOR)
     ui.append(controls)
 
@@ -1321,6 +1323,240 @@ def _build_scene_inventory():
     return scene
 
 
+# ---------------------------------------------------------------------------
+# Scene 8: Entity Animation (engine-native, all formats)
+# ---------------------------------------------------------------------------
+def _format_frame_list(fmt, anim_name, direction):
+    """Convert animation def to flat sprite index list for Entity.animate()."""
+    anim = fmt.animations[anim_name]
+    return [fmt.sprite_index(f.col, direction) for f in anim.frames]
+
+
+def _format_duration(fmt, anim_name):
+    """Total duration in seconds."""
+    anim = fmt.animations[anim_name]
+    return sum(f.duration for f in anim.frames) / 1000.0
+
+
+def _build_scene_entity_anim():
+    scene = mcrfpy.Scene("entity_anim")
+    sheets = _available_sheets()
+    if not sheets:
+        return _no_assets_fallback(scene, "Entity Animation")
+
+    ui = scene.children
+    bg = mcrfpy.Frame(pos=(0, 0), size=(1024, 768), fill_color=BG)
+    ui.append(bg)
+
+    title = mcrfpy.Caption(text="[8] Entity Animation (engine-native loop)",
+                           pos=(20, 10), fill_color=TITLE_COLOR)
+    ui.append(title)
+
+    explain = mcrfpy.Caption(
+        text="Entity.animate('sprite_index', [frames], duration, loop=True) - no Python timer needed",
+        pos=(20, 40), fill_color=LABEL_COLOR)
+    ui.append(explain)
+
+    # Collect all format sections
+    # Each section: format, texture path, available animations, grid + entities
+    sections = []  # (fmt, name, tex, grid, entities, anim_names)
+
+    state = {"anim_idx": 0, "dir_idx": 0}
+
+    section_y = 80
+    grid_w, grid_h = 200, 160
+
+    # --- PUNY_24 ---
+    puny24_lbl = mcrfpy.Caption(text="PUNY_24 (8-dir, free)",
+                                pos=(20, section_y), fill_color=ACCENT_COLOR)
+    ui.append(puny24_lbl)
+
+    fmt24 = PUNY_24
+    tex24 = mcrfpy.Texture(sheets[0], fmt24.tile_w, fmt24.tile_h)
+    grid24 = mcrfpy.Grid(grid_size=(8, 1), texture=tex24,
+                         pos=(20, section_y + 25), size=(grid_w * 2, grid_h))
+    grid24.zoom = 0.25
+    ui.append(grid24)
+
+    entities24 = []
+    anim_names24 = list(fmt24.animations.keys())
+    for i, d in enumerate(Direction):
+        e = mcrfpy.Entity(grid_pos=(i, 0), texture=tex24, sprite_index=0)
+        grid24.entities.append(e)
+        entities24.append(e)
+    sections.append((fmt24, "PUNY_24", tex24, grid24, entities24, anim_names24))
+
+    # Direction labels for compass
+    for i, d in enumerate(Direction):
+        lbl = mcrfpy.Caption(text=d.name, pos=(20 + i * 50, section_y + 25 + grid_h + 2),
+                             fill_color=DIM_COLOR)
+        ui.append(lbl)
+
+    # --- PUNY_29 (if paid sheets exist with 29 cols) ---
+    # PUNY_29 uses 928px wide sheets; check if any available are that size
+    puny29_sheet = None
+    for s in sheets:
+        try:
+            # Try loading as PUNY_29 to check
+            t = mcrfpy.Texture(s, PUNY_29.tile_w, PUNY_29.tile_h)
+            # Check column count via sprite count (29 cols * 8 rows = 232)
+            puny29_sheet = s
+            break
+        except Exception:
+            pass
+
+    section_y2 = section_y + grid_h + 45
+    if puny29_sheet:
+        puny29_lbl = mcrfpy.Caption(text="PUNY_29 (8-dir, paid - extra anims)",
+                                    pos=(20, section_y2), fill_color=ACCENT_COLOR)
+        ui.append(puny29_lbl)
+
+        fmt29 = PUNY_29
+        tex29 = mcrfpy.Texture(puny29_sheet, fmt29.tile_w, fmt29.tile_h)
+        grid29 = mcrfpy.Grid(grid_size=(8, 1), texture=tex29,
+                             pos=(20, section_y2 + 25), size=(grid_w * 2, grid_h))
+        grid29.zoom = 0.25
+        ui.append(grid29)
+
+        entities29 = []
+        anim_names29 = list(fmt29.animations.keys())
+        for i, d in enumerate(Direction):
+            e = mcrfpy.Entity(grid_pos=(i, 0), texture=tex29, sprite_index=0)
+            grid29.entities.append(e)
+            entities29.append(e)
+        sections.append((fmt29, "PUNY_29", tex29, grid29, entities29, anim_names29))
+    else:
+        puny29_lbl = mcrfpy.Caption(text="PUNY_29 (not available - need 928px wide sheet)",
+                                    pos=(20, section_y2), fill_color=DIM_COLOR)
+        ui.append(puny29_lbl)
+
+    # --- SLIME ---
+    section_y3 = section_y2 + grid_h + 45
+    slime_p = _slime_path()
+    if slime_p:
+        slime_lbl = mcrfpy.Caption(text="SLIME (1-dir, non-directional)",
+                                   pos=(20, section_y3), fill_color=ACCENT_COLOR)
+        ui.append(slime_lbl)
+
+        fmt_slime = SLIME
+        tex_slime = mcrfpy.Texture(slime_p, fmt_slime.tile_w, fmt_slime.tile_h)
+        grid_slime = mcrfpy.Grid(grid_size=(2, 1), texture=tex_slime,
+                                 pos=(20, section_y3 + 25), size=(120, grid_h))
+        grid_slime.zoom = 0.25
+        ui.append(grid_slime)
+
+        entities_slime = []
+        anim_names_slime = list(fmt_slime.animations.keys())
+        for i, aname in enumerate(anim_names_slime):
+            e = mcrfpy.Entity(grid_pos=(i, 0), texture=tex_slime, sprite_index=0)
+            grid_slime.entities.append(e)
+            entities_slime.append(e)
+
+        slime_note = mcrfpy.Caption(
+            text="idle / walk", pos=(20, section_y3 + 25 + grid_h + 2),
+            fill_color=DIM_COLOR)
+        ui.append(slime_note)
+
+        sections.append((fmt_slime, "SLIME", tex_slime, grid_slime,
+                         entities_slime, anim_names_slime))
+    else:
+        slime_lbl = mcrfpy.Caption(text="SLIME (not available)",
+                                   pos=(20, section_y3), fill_color=DIM_COLOR)
+        ui.append(slime_lbl)
+
+    # --- Info panel (right side) ---
+    info_x = 500
+    anim_info = mcrfpy.Caption(text="Animation: idle", pos=(info_x, 80),
+                               fill_color=HIGHLIGHT_COLOR)
+    ui.append(anim_info)
+    dir_info = mcrfpy.Caption(text="Direction: S (0)", pos=(info_x, 110),
+                              fill_color=LABEL_COLOR)
+    ui.append(dir_info)
+    frame_info = mcrfpy.Caption(text="", pos=(info_x, 140),
+                                fill_color=ACCENT_COLOR)
+    ui.append(frame_info)
+
+    # Code example
+    code_y = 200
+    code_lines = [
+        "# Engine-native sprite frame animation:",
+        "frames = [fmt.sprite_index(f.col, dir)",
+        "          for f in fmt.animations['walk'].frames]",
+        "entity.animate('sprite_index', frames,",
+        "               duration, loop=True)",
+        "",
+        "# No Python Timer or AnimatedSprite needed!",
+        "# The C++ AnimationManager handles the loop.",
+    ]
+    for i, line in enumerate(code_lines):
+        c = mcrfpy.Caption(text=line, pos=(info_x, code_y + i * 25),
+                           fill_color=mcrfpy.Color(150, 200, 150))
+        ui.append(c)
+
+    # Show all available animation names per format
+    names_y = code_y + len(code_lines) * 25 + 20
+    for fmt, name, _, _, _, anim_names in sections:
+        albl = mcrfpy.Caption(
+            text=f"{name}: {', '.join(anim_names)}",
+            pos=(info_x, names_y), fill_color=DIM_COLOR)
+        ui.append(albl)
+        names_y += 25
+
+    def _apply_anims():
+        """Apply current animation to all entities in all sections."""
+        d = Direction(state["dir_idx"])
+        for fmt, name, tex, grid, entities, anim_names in sections:
+            idx = state["anim_idx"] % len(anim_names)
+            anim_name = anim_names[idx]
+            frames = _format_frame_list(fmt, anim_name, d)
+            dur = _format_duration(fmt, anim_name)
+            is_loop = fmt.animations[anim_name].loop
+
+            for e in entities:
+                e.animate("sprite_index", frames, dur, loop=is_loop)
+
+        # Use first section for info display
+        if sections:
+            fmt0, _, _, _, _, anames0 = sections[0]
+            idx0 = state["anim_idx"] % len(anames0)
+            aname = anames0[idx0]
+            adef = fmt0.animations[aname]
+            nf = len(adef.frames)
+            loop_str = "loop" if adef.loop else "one-shot"
+            chain_str = f" -> {adef.chain_to}" if adef.chain_to else ""
+            anim_info.text = f"Animation: {aname}"
+            frame_info.text = f"Frames: {nf}  ({loop_str}{chain_str})"
+        dir_info.text = f"Direction: {d.name} ({d.value})"
+
+    _apply_anims()
+
+    controls = mcrfpy.Caption(
+        text="[A/D] Animation  [W/S] Direction  [1-8] Scenes",
+        pos=(20, 740), fill_color=DIM_COLOR)
+    ui.append(controls)
+
+    def on_key(key, action):
+        if action != mcrfpy.InputState.PRESSED:
+            return
+        if _handle_scene_switch(key):
+            return
+        if key == mcrfpy.Key.A:
+            state["anim_idx"] -= 1
+            _apply_anims()
+        elif key == mcrfpy.Key.D:
+            state["anim_idx"] += 1
+            _apply_anims()
+        elif key == mcrfpy.Key.W:
+            state["dir_idx"] = (state["dir_idx"] - 1) % 8
+            _apply_anims()
+        elif key == mcrfpy.Key.S:
+            state["dir_idx"] = (state["dir_idx"] + 1) % 8
+            _apply_anims()
+
+    scene.on_key = on_key
+    return scene
+
+
 # ---------------------------------------------------------------------------
 # Main
 # ---------------------------------------------------------------------------
@@ -1338,6 +1574,7 @@ def main():
     _build_scene_layers()
     _build_scene_equip()
     _build_scene_inventory()
+    _build_scene_entity_anim()
 
     # Start animation timer (20fps animation updates)
     # Keep a reference so the Python cache lookup works and (timer, runtime) is passed

src/3d/Entity3D.cpp

@@ -1141,19 +1141,20 @@ PyObject* Entity3D::py_update_visibility(PyEntity3DObject* self, PyObject* args)
 
 PyObject* Entity3D::py_animate(PyEntity3DObject* self, PyObject* args, PyObject* kwds)
 {
-    static const char* keywords[] = {"property", "target", "duration", "easing", "delta", "callback", "conflict_mode", nullptr};
+    static const char* keywords[] = {"property", "target", "duration", "easing", "delta", "loop", "callback", "conflict_mode", nullptr};
 
     const char* property_name;
     PyObject* target_value;
     float duration;
     PyObject* easing_arg = Py_None;
     int delta = 0;
+    int loop_val = 0;
     PyObject* callback = nullptr;
     const char* conflict_mode_str = nullptr;
 
-    if (!PyArg_ParseTupleAndKeywords(args, kwds, "sOf|OpOs", const_cast<char**>(keywords),
+    if (!PyArg_ParseTupleAndKeywords(args, kwds, "sOf|OppOs", const_cast<char**>(keywords),
                                       &property_name, &target_value, &duration,
-                                      &easing_arg, &delta, &callback, &conflict_mode_str)) {
+                                      &easing_arg, &delta, &loop_val, &callback, &conflict_mode_str)) {
         return NULL;
     }
 
@@ -1216,7 +1217,7 @@ PyObject* Entity3D::py_animate(PyEntity3DObject* self, PyObject* args, PyObject*
     }
 
     // Create the Animation
-    auto animation = std::make_shared<Animation>(property_name, animValue, duration, easingFunc, delta != 0, callback);
+    auto animation = std::make_shared<Animation>(property_name, animValue, duration, easingFunc, delta != 0, loop_val != 0, callback);
 
     // Start on this entity (uses startEntity3D)
     animation->startEntity3D(self->data);

src/Animation.cpp

@@ -33,12 +33,14 @@ Animation::Animation(const std::string& targetProperty,
                      float duration,
                      EasingFunction easingFunc,
                      bool delta,
+                     bool loop,
                      PyObject* callback)
     : targetProperty(targetProperty)
     , targetValue(targetValue)
     , duration(duration)
     , easingFunc(easingFunc)
     , delta(delta)
+    , loop(loop)
     , pythonCallback(callback)
 {
     // Increase reference count for Python callback
@@ -123,7 +125,7 @@ void Animation::start(std::shared_ptr<UIDrawable> target) {
 
     // For zero-duration animations, apply final value immediately
     if (duration <= 0.0f) {
-        AnimationValue finalValue = interpolate(1.0f);
+        AnimationValue finalValue = interpolate(easingFunc(1.0f));
         applyValue(target.get(), finalValue);
         if (pythonCallback && !callbackTriggered) {
             triggerCallback();
@@ -155,12 +157,18 @@ void Animation::startEntity(std::shared_ptr<UIEntity> target) {
                 startValue = target->sprite.getSpriteIndex();
             }
         }
+        else if constexpr (std::is_same_v<T, std::vector<int>>) {
+            // For sprite animation frame lists, get current sprite index
+            if (targetProperty == "sprite_index" || targetProperty == "sprite_number") {
+                startValue = target->sprite.getSpriteIndex();
+            }
+        }
         // Entities don't support other types yet
     }, targetValue);
 
     // For zero-duration animations, apply final value immediately
     if (duration <= 0.0f) {
-        AnimationValue finalValue = interpolate(1.0f);
+        AnimationValue finalValue = interpolate(easingFunc(1.0f));
         applyValue(target.get(), finalValue);
         if (pythonCallback && !callbackTriggered) {
             triggerCallback();
@@ -198,7 +206,7 @@ void Animation::startEntity3D(std::shared_ptr<mcrf::Entity3D> target) {
 
     // For zero-duration animations, apply final value immediately
     if (duration <= 0.0f) {
-        AnimationValue finalValue = interpolate(1.0f);
+        AnimationValue finalValue = interpolate(easingFunc(1.0f));
         applyValue(target.get(), finalValue);
         if (pythonCallback && !callbackTriggered) {
             triggerCallback();
@@ -228,17 +236,20 @@ void Animation::complete() {
     // Jump to end of animation
     elapsed = duration;
 
-    // Apply final value
+    // Apply final value through easing function
+    // For standard easings, easingFunc(1.0) = 1.0 (no change)
+    // For ping-pong easings, easingFunc(1.0) = 0.0 (returns to start value)
+    float finalT = easingFunc(1.0f);
     if (auto target = targetWeak.lock()) {
-        AnimationValue finalValue = interpolate(1.0f);
+        AnimationValue finalValue = interpolate(finalT);
         applyValue(target.get(), finalValue);
     }
     else if (auto entity = entityTargetWeak.lock()) {
-        AnimationValue finalValue = interpolate(1.0f);
+        AnimationValue finalValue = interpolate(finalT);
         applyValue(entity.get(), finalValue);
     }
     else if (auto entity3d = entity3dTargetWeak.lock()) {
-        AnimationValue finalValue = interpolate(1.0f);
+        AnimationValue finalValue = interpolate(finalT);
         applyValue(entity3d.get(), finalValue);
     }
 }
@@ -269,8 +280,9 @@ bool Animation::update(float deltaTime) {
     // Apply final value once before returning
     if (isComplete()) {
         if (!callbackTriggered) {
-            // Apply final value for zero-duration animations
+            // Apply final value through easing function
-            AnimationValue finalValue = interpolate(1.0f);
+            float finalT = easingFunc(1.0f);
+            AnimationValue finalValue = interpolate(finalT);
             if (target) {
                 applyValue(target.get(), finalValue);
             } else if (entity) {
@@ -288,7 +300,11 @@ bool Animation::update(float deltaTime) {
     }
 
     elapsed += deltaTime;
-    elapsed = std::min(elapsed, duration);
+    if (loop && duration > 0.0f) {
+        while (elapsed >= duration) elapsed -= duration;
+    } else {
+        elapsed = std::min(elapsed, duration);
+    }
 
     // Calculate easing value (0.0 to 1.0)
     float t = duration > 0 ? elapsed / duration : 1.0f;
@@ -722,8 +738,9 @@ void Animation::triggerCallback() {
         return;
     }
 
-    // Final value (interpolated at t=1.0)
+    // Final value (interpolated through easing function at t=1.0)
-    PyObject* valueObj = animationValueToPython(interpolate(1.0f));
+    // For ping-pong easings, this returns the start value (easingFunc(1.0) = 0.0)
+    PyObject* valueObj = animationValueToPython(interpolate(easingFunc(1.0f)));
     if (!valueObj) {
         Py_DECREF(targetObj);
         Py_DECREF(propertyObj);
@@ -956,6 +973,38 @@ float easeInOutBounce(float t) {
     }
 }
 
+// Ping-pong easing functions (0 -> 1 -> 0)
+// These are designed for looping animations where the value should
+// smoothly return to the start position each cycle.
+
+float pingPong(float t) {
+    // Linear triangle wave: 0 -> 1 -> 0
+    return 1.0f - std::fabs(2.0f * t - 1.0f);
+}
+
+float pingPongSmooth(float t) {
+    // Sine bell curve: smooth acceleration and deceleration
+    return std::sin(static_cast<float>(M_PI) * t);
+}
+
+float pingPongEaseIn(float t) {
+    // Quadratic ease at rest positions (smooth departure/return, sharp peak)
+    float pp = 1.0f - std::fabs(2.0f * t - 1.0f);
+    return pp * pp;
+}
+
+float pingPongEaseOut(float t) {
+    // Ease-out at peak (sharp departure, smooth turnaround)
+    float pp = 1.0f - std::fabs(2.0f * t - 1.0f);
+    return pp * (2.0f - pp);
+}
+
+float pingPongEaseInOut(float t) {
+    // sin^2: smooth everywhere including at loop seam
+    float s = std::sin(static_cast<float>(M_PI) * t);
+    return s * s;
+}
+
 // Get easing function by name
 EasingFunction getByName(const std::string& name) {
     static std::unordered_map<std::string, EasingFunction> easingMap = {
@@ -989,7 +1038,12 @@ EasingFunction getByName(const std::string& name) {
         {"easeInOutBack", easeInOutBack},
         {"easeInBounce", easeInBounce},
         {"easeOutBounce", easeOutBounce},
-        {"easeInOutBounce", easeInOutBounce}
+        {"easeInOutBounce", easeInOutBounce},
+        {"pingPong", pingPong},
+        {"pingPongSmooth", pingPongSmooth},
+        {"pingPongEaseIn", pingPongEaseIn},
+        {"pingPongEaseOut", pingPongEaseOut},
+        {"pingPongEaseInOut", pingPongEaseInOut}
     };
     
     auto it = easingMap.find(name);

src/Animation.h

@@ -49,6 +49,7 @@ public:
               float duration,
               EasingFunction easingFunc = EasingFunctions::linear,
               bool delta = false,
+              bool loop = false,
               PyObject* callback = nullptr);
     
     // Destructor - cleanup Python callback reference
@@ -86,9 +87,10 @@ public:
     std::string getTargetProperty() const { return targetProperty; }
     float getDuration() const { return duration; }
     float getElapsed() const { return elapsed; }
-    bool isComplete() const { return elapsed >= duration || stopped; }
+    bool isComplete() const { return (!loop && elapsed >= duration) || stopped; }
     bool isStopped() const { return stopped; }
     bool isDelta() const { return delta; }
+    bool isLooping() const { return loop; }
 
     // Get raw target pointer for property locking (#120)
     void* getTargetPtr() const {
@@ -106,6 +108,7 @@ private:
     float elapsed = 0.0f;          // Elapsed time
     EasingFunction easingFunc;     // Easing function to use
     bool delta;                    // If true, targetValue is relative to start
+    bool loop;                     // If true, animation repeats from start when complete
     bool stopped = false;          // If true, animation was stopped without completing
     
     // RAII: Use weak_ptr for safe target tracking
@@ -178,6 +181,13 @@ namespace EasingFunctions {
     float easeOutBounce(float t);
     float easeInOutBounce(float t);
 
+    // Ping-pong easing functions (0 -> 1 -> 0, for looping animations)
+    float pingPong(float t);
+    float pingPongSmooth(float t);
+    float pingPongEaseIn(float t);
+    float pingPongEaseOut(float t);
+    float pingPongEaseInOut(float t);
+
     // Get easing function by name
     EasingFunction getByName(const std::string& name);
 }

src/PyAnimation.cpp

@@ -20,17 +20,18 @@ PyObject* PyAnimation::create(PyTypeObject* type, PyObject* args, PyObject* kwds
 }
 
 int PyAnimation::init(PyAnimationObject* self, PyObject* args, PyObject* kwds) {
-    static const char* keywords[] = {"property", "target", "duration", "easing", "delta", "callback", nullptr};
+    static const char* keywords[] = {"property", "target", "duration", "easing", "delta", "loop", "callback", nullptr};
 
     const char* property_name;
     PyObject* target_value;
     float duration;
     PyObject* easing_arg = Py_None;
     int delta = 0;
+    int loop_val = 0;
     PyObject* callback = nullptr;
 
-    if (!PyArg_ParseTupleAndKeywords(args, kwds, "sOf|OpO", const_cast<char**>(keywords),
+    if (!PyArg_ParseTupleAndKeywords(args, kwds, "sOf|OppO", const_cast<char**>(keywords),
-                                      &property_name, &target_value, &duration, &easing_arg, &delta, &callback)) {
+                                      &property_name, &target_value, &duration, &easing_arg, &delta, &loop_val, &callback)) {
         return -1;
     }
     
@@ -107,7 +108,7 @@ int PyAnimation::init(PyAnimationObject* self, PyObject* args, PyObject* kwds) {
     }
 
     // Create the Animation
-    self->data = std::make_shared<Animation>(property_name, animValue, duration, easingFunc, delta != 0, callback);
+    self->data = std::make_shared<Animation>(property_name, animValue, duration, easingFunc, delta != 0, loop_val != 0, callback);
 
     return 0;
 }
@@ -179,6 +180,10 @@ PyObject* PyAnimation::get_is_delta(PyAnimationObject* self, void* closure) {
     return PyBool_FromLong(self->data->isDelta());
 }
 
+PyObject* PyAnimation::get_is_looping(PyAnimationObject* self, void* closure) {
+    return PyBool_FromLong(self->data->isLooping());
+}
+
 // Helper to convert Python string to AnimationConflictMode
 static bool parseConflictMode(const char* mode_str, AnimationConflictMode& mode) {
     if (!mode_str || strcmp(mode_str, "replace") == 0) {
@@ -356,6 +361,8 @@ PyGetSetDef PyAnimation::getsetters[] = {
      MCRF_PROPERTY(is_complete, "Whether animation is complete (bool, read-only). True when elapsed >= duration or complete() was called."), NULL},
     {"is_delta", (getter)get_is_delta, NULL,
      MCRF_PROPERTY(is_delta, "Whether animation uses delta mode (bool, read-only). In delta mode, the target value is added to the starting value."), NULL},
+    {"is_looping", (getter)get_is_looping, NULL,
+     MCRF_PROPERTY(is_looping, "Whether animation loops (bool, read-only). Looping animations repeat from the start when they reach the end."), NULL},
     {NULL}
 };
 

src/PyAnimation.h

@@ -24,6 +24,7 @@ public:
     static PyObject* get_elapsed(PyAnimationObject* self, void* closure);
     static PyObject* get_is_complete(PyAnimationObject* self, void* closure);
     static PyObject* get_is_delta(PyAnimationObject* self, void* closure);
+    static PyObject* get_is_looping(PyAnimationObject* self, void* closure);
     
     // Methods
     static PyObject* start(PyAnimationObject* self, PyObject* args, PyObject* kwds);
@@ -47,7 +48,7 @@ namespace mcrfpydef {
         .tp_repr = (reprfunc)PyAnimation::repr,
         .tp_flags = Py_TPFLAGS_DEFAULT,
         .tp_doc = PyDoc_STR(
-            "Animation(property: str, target: Any, duration: float, easing: str = 'linear', delta: bool = False, callback: Callable = None)\n"
+            "Animation(property: str, target: Any, duration: float, easing: str = 'linear', delta: bool = False, loop: bool = False, callback: Callable = None)\n"
             "\n"
             "Create an animation that interpolates a property value over time.\n"
             "\n"
@@ -80,22 +81,18 @@ namespace mcrfpydef {
             "        - 'easeInBack', 'easeOutBack', 'easeInOutBack'\n"
             "        - 'easeInBounce', 'easeOutBounce', 'easeInOutBounce'\n"
             "    delta: If True, target is relative to start value (additive). Default False.\n"
-            "    callback: Function(animation, target) called when animation completes.\n"
+            "    loop: If True, animation repeats from start when it reaches the end. Default False.\n"
+            "    callback: Function(target, property, value) called when animation completes.\n"
+            "        Not called for looping animations (since they never complete).\n"
             "\n"
             "Example:\n"
             "    # Move a frame from current position to x=500 over 2 seconds\n"
             "    anim = mcrfpy.Animation('x', 500.0, 2.0, 'easeInOut')\n"
             "    anim.start(my_frame)\n"
             "\n"
-            "    # Fade out with callback\n"
+            "    # Looping sprite animation\n"
-            "    def on_done(anim, target):\n"
+            "    walk = mcrfpy.Animation('sprite_index', [0,1,2,3,2,1], 0.6, loop=True)\n"
-            "        print('Animation complete!')\n"
+            "    walk.start(my_sprite)\n"
-            "    fade = mcrfpy.Animation('fill_color.a', 0, 1.0, callback=on_done)\n"
-            "    fade.start(my_sprite)\n"
-            "\n"
-            "    # Animate through sprite frames\n"
-            "    walk_cycle = mcrfpy.Animation('sprite_index', [0,1,2,3,2,1], 0.5, 'linear')\n"
-            "    walk_cycle.start(my_entity)\n"
         ),
         .tp_methods = PyAnimation::methods,
         .tp_getset = PyAnimation::getsetters,

src/PyEasing.cpp

@@ -43,6 +43,11 @@ static const EasingEntry easing_table[] = {
     {"EASE_IN_BOUNCE", 28, EasingFunctions::easeInBounce},
     {"EASE_OUT_BOUNCE", 29, EasingFunctions::easeOutBounce},
     {"EASE_IN_OUT_BOUNCE", 30, EasingFunctions::easeInOutBounce},
+    {"PING_PONG", 31, EasingFunctions::pingPong},
+    {"PING_PONG_SMOOTH", 32, EasingFunctions::pingPongSmooth},
+    {"PING_PONG_EASE_IN", 33, EasingFunctions::pingPongEaseIn},
+    {"PING_PONG_EASE_OUT", 34, EasingFunctions::pingPongEaseOut},
+    {"PING_PONG_EASE_IN_OUT", 35, EasingFunctions::pingPongEaseInOut},
 };
 
 // Old string names (for backwards compatibility)
@@ -56,7 +61,9 @@ static const char* legacy_names[] = {
     "easeInCirc", "easeOutCirc", "easeInOutCirc",
     "easeInElastic", "easeOutElastic", "easeInOutElastic",
     "easeInBack", "easeOutBack", "easeInOutBack",
-    "easeInBounce", "easeOutBounce", "easeInOutBounce"
+    "easeInBounce", "easeOutBounce", "easeInOutBounce",
+    "pingPong", "pingPongSmooth", "pingPongEaseIn",
+    "pingPongEaseOut", "pingPongEaseInOut"
 };
 
 static const int NUM_EASING_ENTRIES = sizeof(easing_table) / sizeof(easing_table[0]);

src/UIBase.h

@@ -110,7 +110,7 @@ static PyObject* UIDrawable_animate(T* self, PyObject* args, PyObject* kwds)
     UIDRAWABLE_METHODS_BASE, \
     {"animate", (PyCFunction)UIDrawable_animate<PyObjectType>, METH_VARARGS | METH_KEYWORDS, \
      MCRF_METHOD(Drawable, animate, \
-         MCRF_SIG("(property: str, target: Any, duration: float, easing=None, delta=False, callback=None, conflict_mode='replace')", "Animation"), \
+         MCRF_SIG("(property: str, target: Any, duration: float, easing=None, delta=False, loop=False, callback=None, conflict_mode='replace')", "Animation"), \
          MCRF_DESC("Create and start an animation on this drawable's property."), \
          MCRF_ARGS_START \
          MCRF_ARG("property", "Name of the property to animate (e.g., 'x', 'fill_color', 'opacity')") \
@@ -118,7 +118,8 @@ static PyObject* UIDrawable_animate(T* self, PyObject* args, PyObject* kwds)
          MCRF_ARG("duration", "Animation duration in seconds") \
          MCRF_ARG("easing", "Easing function: Easing enum value, string name, or None for linear") \
          MCRF_ARG("delta", "If True, target is relative to current value; if False, target is absolute") \
-         MCRF_ARG("callback", "Optional callable invoked when animation completes") \
+         MCRF_ARG("loop", "If True, animation repeats from start when it reaches the end (default False)") \
+         MCRF_ARG("callback", "Optional callable invoked when animation completes (not called for looping animations)") \
          MCRF_ARG("conflict_mode", "'replace' (default), 'queue', or 'error' if property already animating") \
          MCRF_RETURNS("Animation object for monitoring progress") \
          MCRF_RAISES("ValueError", "If property name is not valid for this drawable type") \

src/UIDrawable.cpp

@@ -1845,19 +1845,20 @@ int UIDrawable::set_on_move(PyObject* self, PyObject* value, void* closure) {
 // Animation shorthand helper - creates and starts an animation on a UIDrawable
 // This is a free function (not a member) to avoid incomplete type issues in UIBase.h template
 PyObject* UIDrawable_animate_impl(std::shared_ptr<UIDrawable> self, PyObject* args, PyObject* kwds) {
-    static const char* keywords[] = {"property", "target", "duration", "easing", "delta", "callback", "conflict_mode", nullptr};
+    static const char* keywords[] = {"property", "target", "duration", "easing", "delta", "loop", "callback", "conflict_mode", nullptr};
 
     const char* property_name;
     PyObject* target_value;
     float duration;
     PyObject* easing_arg = Py_None;
     int delta = 0;
+    int loop_val = 0;
     PyObject* callback = nullptr;
     const char* conflict_mode_str = nullptr;
 
-    if (!PyArg_ParseTupleAndKeywords(args, kwds, "sOf|OpOs", const_cast<char**>(keywords),
+    if (!PyArg_ParseTupleAndKeywords(args, kwds, "sOf|OppOs", const_cast<char**>(keywords),
                                       &property_name, &target_value, &duration,
-                                      &easing_arg, &delta, &callback, &conflict_mode_str)) {
+                                      &easing_arg, &delta, &loop_val, &callback, &conflict_mode_str)) {
         return NULL;
     }
 
@@ -1961,7 +1962,7 @@ PyObject* UIDrawable_animate_impl(std::shared_ptr<UIDrawable> self, PyObject* ar
     }
 
     // Create the Animation
-    auto animation = std::make_shared<Animation>(property_name, animValue, duration, easingFunc, delta != 0, callback);
+    auto animation = std::make_shared<Animation>(property_name, animValue, duration, easingFunc, delta != 0, loop_val != 0, callback);
 
     // Start on this drawable
     animation->start(self);

src/UIEntity.cpp

@@ -945,19 +945,21 @@ PyMethodDef UIEntity_all_methods[] = {
     UIDRAWABLE_METHODS_BASE,
     {"animate", (PyCFunction)UIEntity::animate, METH_VARARGS | METH_KEYWORDS,
      MCRF_METHOD(Entity, animate,
-         MCRF_SIG("(property: str, target: Any, duration: float, easing=None, delta=False, callback=None, conflict_mode='replace')", "Animation"),
+         MCRF_SIG("(property: str, target: Any, duration: float, easing=None, delta=False, loop=False, callback=None, conflict_mode='replace')", "Animation"),
          MCRF_DESC("Create and start an animation on this entity's property."),
          MCRF_ARGS_START
          MCRF_ARG("property", "Name of the property to animate: 'draw_x', 'draw_y' (tile coords), 'sprite_scale', 'sprite_index'")
-         MCRF_ARG("target", "Target value - float or int depending on property")
+         MCRF_ARG("target", "Target value - float, int, or list of int (for sprite frame sequences)")
          MCRF_ARG("duration", "Animation duration in seconds")
          MCRF_ARG("easing", "Easing function: Easing enum value, string name, or None for linear")
          MCRF_ARG("delta", "If True, target is relative to current value; if False, target is absolute")
-         MCRF_ARG("callback", "Optional callable invoked when animation completes")
+         MCRF_ARG("loop", "If True, animation repeats from start when it reaches the end (default False)")
+         MCRF_ARG("callback", "Optional callable invoked when animation completes (not called for looping animations)")
          MCRF_ARG("conflict_mode", "'replace' (default), 'queue', or 'error' if property already animating")
          MCRF_RETURNS("Animation object for monitoring progress")
          MCRF_RAISES("ValueError", "If property name is not valid for Entity (draw_x, draw_y, sprite_scale, sprite_index)")
-         MCRF_NOTE("Use 'draw_x'/'draw_y' to animate tile coordinates for smooth movement between grid cells.")
+         MCRF_NOTE("Use 'draw_x'/'draw_y' to animate tile coordinates for smooth movement between grid cells. "
+                   "Use list target with loop=True for repeating sprite frame animations.")
      )},
     {"at", (PyCFunction)UIEntity::at, METH_VARARGS | METH_KEYWORDS,
      "at(x, y) or at(pos) -> GridPointState\n\n"
@@ -1136,19 +1138,20 @@ bool UIEntity::hasProperty(const std::string& name) const {
 
 // Animation shorthand for Entity - creates and starts an animation
 PyObject* UIEntity::animate(PyUIEntityObject* self, PyObject* args, PyObject* kwds) {
-    static const char* keywords[] = {"property", "target", "duration", "easing", "delta", "callback", "conflict_mode", nullptr};
+    static const char* keywords[] = {"property", "target", "duration", "easing", "delta", "loop", "callback", "conflict_mode", nullptr};
 
     const char* property_name;
     PyObject* target_value;
     float duration;
     PyObject* easing_arg = Py_None;
     int delta = 0;
+    int loop_val = 0;
     PyObject* callback = nullptr;
     const char* conflict_mode_str = nullptr;
 
-    if (!PyArg_ParseTupleAndKeywords(args, kwds, "sOf|OpOs", const_cast<char**>(keywords),
+    if (!PyArg_ParseTupleAndKeywords(args, kwds, "sOf|OppOs", const_cast<char**>(keywords),
                                       &property_name, &target_value, &duration,
-                                      &easing_arg, &delta, &callback, &conflict_mode_str)) {
+                                      &easing_arg, &delta, &loop_val, &callback, &conflict_mode_str)) {
         return NULL;
     }
 
@@ -1173,7 +1176,7 @@ PyObject* UIEntity::animate(PyUIEntityObject* self, PyObject* args, PyObject* kw
     }
 
     // Convert Python target value to AnimationValue
-    // Entity only supports float and int properties
+    // Entity supports float, int, and list of int (for sprite frame animation)
     AnimationValue animValue;
 
     if (PyFloat_Check(target_value)) {
@@ -1182,8 +1185,23 @@ PyObject* UIEntity::animate(PyUIEntityObject* self, PyObject* args, PyObject* kw
     else if (PyLong_Check(target_value)) {
         animValue = static_cast<int>(PyLong_AsLong(target_value));
     }
+    else if (PyList_Check(target_value)) {
+        // List of integers for sprite animation
+        std::vector<int> indices;
+        Py_ssize_t size = PyList_Size(target_value);
+        for (Py_ssize_t i = 0; i < size; i++) {
+            PyObject* item = PyList_GetItem(target_value, i);
+            if (PyLong_Check(item)) {
+                indices.push_back(PyLong_AsLong(item));
+            } else {
+                PyErr_SetString(PyExc_TypeError, "Sprite animation list must contain only integers");
+                return NULL;
+            }
+        }
+        animValue = indices;
+    }
     else {
-        PyErr_SetString(PyExc_TypeError, "Entity animations only support float or int target values");
+        PyErr_SetString(PyExc_TypeError, "Entity animations support float, int, or list of int target values");
         return NULL;
     }
 
@@ -1210,7 +1228,7 @@ PyObject* UIEntity::animate(PyUIEntityObject* self, PyObject* args, PyObject* kw
     }
 
     // Create the Animation
-    auto animation = std::make_shared<Animation>(property_name, animValue, duration, easingFunc, delta != 0, callback);
+    auto animation = std::make_shared<Animation>(property_name, animValue, duration, easingFunc, delta != 0, loop_val != 0, callback);
 
     // Start on this entity (uses startEntity, not start)
     animation->startEntity(self->data);

tests/unit/animation_loop_test.py

@@ -0,0 +1,107 @@
+"""Test Animation loop parameter.
+
+Verifies that loop=True causes animations to cycle instead of completing.
+"""
+import mcrfpy
+import sys
+
+PASS = True
+def check(name, condition):
+    global PASS
+    if not condition:
+        print(f"FAIL: {name}")
+        PASS = False
+    else:
+        print(f"  ok: {name}")
+
+
+# --- Setup ---
+scene = mcrfpy.Scene("test")
+mcrfpy.current_scene = scene
+
+# --- Test 1: Default loop=False, animation completes ---
+sprite = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite)
+anim = sprite.animate("x", 100.0, 1.0)
+check("default loop is False", anim.is_looping == False)
+
+# Step past duration
+for _ in range(15):
+    mcrfpy.step(0.1)
+
+check("non-loop animation completes", anim.is_complete == True)
+
+
+# --- Test 2: loop=True, animation does NOT complete ---
+sprite2 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite2)
+anim2 = sprite2.animate("x", 100.0, 0.5, loop=True)
+check("loop=True sets is_looping", anim2.is_looping == True)
+
+# Step well past duration
+for _ in range(20):
+    mcrfpy.step(0.1)
+
+check("looping animation never completes", anim2.is_complete == False)
+check("looping animation has valid target", anim2.hasValidTarget() == True)
+
+
+# --- Test 3: Sprite frame list with loop ---
+sprite3 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite3)
+anim3 = sprite3.animate("sprite_index", [0, 1, 2, 3], 0.4, loop=True)
+check("frame list loop is_looping", anim3.is_looping == True)
+
+# Step through multiple cycles
+for _ in range(20):
+    mcrfpy.step(0.1)
+
+check("frame list loop doesn't complete", anim3.is_complete == False)
+
+
+# --- Test 4: Loop animation can be stopped ---
+sprite4 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite4)
+anim4 = sprite4.animate("x", 200.0, 0.5, loop=True)
+
+for _ in range(10):
+    mcrfpy.step(0.1)
+
+check("loop animation running before stop", anim4.is_complete == False)
+anim4.stop()
+check("loop animation stopped", anim4.is_complete == True)
+
+
+# --- Test 5: Loop animation can be replaced ---
+sprite5 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite5)
+anim5a = sprite5.animate("x", 100.0, 0.5, loop=True)
+
+for _ in range(5):
+    mcrfpy.step(0.1)
+
+# Replace with non-looping
+anim5b = sprite5.animate("x", 200.0, 0.5)
+check("replacement anim is not looping", anim5b.is_looping == False)
+
+for _ in range(10):
+    mcrfpy.step(0.1)
+
+check("replacement anim completes", anim5b.is_complete == True)
+
+
+# --- Test 6: Animation object created with loop=True via constructor ---
+anim6 = mcrfpy.Animation("x", 100.0, 1.0, loop=True)
+check("Animation constructor loop=True", anim6.is_looping == True)
+
+anim7 = mcrfpy.Animation("x", 100.0, 1.0)
+check("Animation constructor default loop=False", anim7.is_looping == False)
+
+
+# --- Summary ---
+if PASS:
+    print("PASS")
+    sys.exit(0)
+else:
+    print("FAIL")
+    sys.exit(1)

tests/unit/entity_framelist_test.py

@@ -0,0 +1,103 @@
+"""Test Entity.animate() with list of int frame indices.
+
+Verifies that Entity supports sprite frame list animation,
+including with loop=True.
+"""
+import mcrfpy
+import sys
+
+PASS = True
+def check(name, condition):
+    global PASS
+    if not condition:
+        print(f"FAIL: {name}")
+        PASS = False
+    else:
+        print(f"  ok: {name}")
+
+
+# --- Setup ---
+scene = mcrfpy.Scene("test")
+mcrfpy.current_scene = scene
+
+# Create a grid with an entity
+tex = mcrfpy.Texture("assets/kenney_tinydungeon.png", 16, 16)
+grid = mcrfpy.Grid(grid_size=(10, 10), texture=tex, pos=(0, 0), size=(320, 320))
+scene.children.append(grid)
+
+entity = mcrfpy.Entity(grid_pos=(1, 1), texture=tex, sprite_index=0)
+grid.entities.append(entity)
+
+
+# --- Test 1: Entity.animate with list target ---
+anim = entity.animate("sprite_index", [0, 1, 2, 3], 0.4)
+check("entity animate with list returns Animation", anim is not None)
+check("entity frame list anim has valid target", anim.hasValidTarget() == True)
+
+# Step to complete
+for _ in range(10):
+    mcrfpy.step(0.1)
+
+check("entity frame list anim completes", anim.is_complete == True)
+
+
+# --- Test 2: Entity.animate with list + loop=True ---
+entity2 = mcrfpy.Entity(grid_pos=(2, 2), texture=tex, sprite_index=0)
+grid.entities.append(entity2)
+
+anim2 = entity2.animate("sprite_index", [10, 11, 12, 13], 0.4, loop=True)
+check("entity loop frame list is_looping", anim2.is_looping == True)
+
+# Step well past duration
+for _ in range(20):
+    mcrfpy.step(0.1)
+
+check("entity loop frame list doesn't complete", anim2.is_complete == False)
+
+# The sprite_index should be one of the frame values
+idx = entity2.sprite_index
+check(f"entity sprite_index is valid frame ({idx})", idx in [10, 11, 12, 13])
+
+
+# --- Test 3: Invalid list items raise TypeError ---
+try:
+    entity.animate("sprite_index", [1, 2, "bad", 4], 0.5)
+    check("invalid list item raises TypeError", False)
+except TypeError:
+    check("invalid list item raises TypeError", True)
+
+
+# --- Test 4: Entity.animate with int still works (no regression) ---
+entity3 = mcrfpy.Entity(grid_pos=(3, 3), texture=tex, sprite_index=0)
+grid.entities.append(entity3)
+
+anim3 = entity3.animate("sprite_index", 5, 0.2)
+check("entity animate with int still works", anim3 is not None)
+
+for _ in range(5):
+    mcrfpy.step(0.1)
+
+check("entity int anim completes", anim3.is_complete == True)
+check("entity sprite_index set to target", entity3.sprite_index == 5)
+
+
+# --- Test 5: Entity.animate with float still works (no regression) ---
+entity4 = mcrfpy.Entity(grid_pos=(4, 4), texture=tex, sprite_index=0)
+grid.entities.append(entity4)
+
+anim4 = entity4.animate("draw_x", 5.0, 0.3)
+check("entity animate with float still works", anim4 is not None)
+
+for _ in range(10):
+    mcrfpy.step(0.1)
+
+check("entity float anim completes", anim4.is_complete == True)
+
+
+# --- Summary ---
+if PASS:
+    print("PASS")
+    sys.exit(0)
+else:
+    print("FAIL")
+    sys.exit(1)

tests/unit/ping_pong_easing_test.py

@@ -0,0 +1,203 @@
+"""Test ping-pong easing functions.
+
+Verifies that ping-pong easings oscillate (0 -> 1 -> 0) and that
+complete()/stop() on ping-pong animations returns to the start value.
+"""
+import mcrfpy
+import sys
+
+PASS = True
+def check(name, condition):
+    global PASS
+    if not condition:
+        print(f"FAIL: {name}")
+        PASS = False
+    else:
+        print(f"  ok: {name}")
+
+
+# --- Setup ---
+scene = mcrfpy.Scene("test")
+mcrfpy.current_scene = scene
+
+
+# --- Test 1: Ping-pong easing enum members exist ---
+check("PING_PONG exists", hasattr(mcrfpy.Easing, "PING_PONG"))
+check("PING_PONG_SMOOTH exists", hasattr(mcrfpy.Easing, "PING_PONG_SMOOTH"))
+check("PING_PONG_EASE_IN exists", hasattr(mcrfpy.Easing, "PING_PONG_EASE_IN"))
+check("PING_PONG_EASE_OUT exists", hasattr(mcrfpy.Easing, "PING_PONG_EASE_OUT"))
+check("PING_PONG_EASE_IN_OUT exists", hasattr(mcrfpy.Easing, "PING_PONG_EASE_IN_OUT"))
+
+# Check enum values are sequential from 31
+check("PING_PONG value is 31", int(mcrfpy.Easing.PING_PONG) == 31)
+check("PING_PONG_EASE_IN_OUT value is 35", int(mcrfpy.Easing.PING_PONG_EASE_IN_OUT) == 35)
+
+
+# --- Test 2: Ping-pong animation reaches midpoint then returns ---
+sprite = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite)
+anim = sprite.animate("x", 100.0, 1.0, mcrfpy.Easing.PING_PONG)
+check("ping-pong anim created", anim is not None)
+
+# Step to midpoint (t=0.5)
+for _ in range(5):
+    mcrfpy.step(0.1)
+
+midpoint_x = sprite.x
+check(f"at midpoint x ({midpoint_x:.1f}) is near 100", midpoint_x > 80.0)
+
+# Step to end (t=1.0)
+for _ in range(5):
+    mcrfpy.step(0.1)
+
+final_x = sprite.x
+check(f"at end x ({final_x:.1f}) returns near 0", final_x < 20.0)
+check("ping-pong anim completes", anim.is_complete == True)
+
+
+# --- Test 3: Ping-pong smooth animation oscillates ---
+sprite2 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite2)
+anim2 = sprite2.animate("x", 200.0, 1.0, mcrfpy.Easing.PING_PONG_SMOOTH)
+
+# Step to midpoint
+for _ in range(5):
+    mcrfpy.step(0.1)
+mid_x2 = sprite2.x
+check(f"smooth midpoint x ({mid_x2:.1f}) is near 200", mid_x2 > 150.0)
+
+# Step to end
+for _ in range(5):
+    mcrfpy.step(0.1)
+final_x2 = sprite2.x
+check(f"smooth end x ({final_x2:.1f}) returns near 0", final_x2 < 20.0)
+
+
+# --- Test 4: Ping-pong with loop=True cycles continuously ---
+sprite3 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite3)
+anim3 = sprite3.animate("x", 100.0, 0.5, mcrfpy.Easing.PING_PONG, loop=True)
+check("ping-pong loop is_looping", anim3.is_looping == True)
+
+# Step through 2 full cycles
+for _ in range(20):
+    mcrfpy.step(0.1)
+
+check("ping-pong loop doesn't complete", anim3.is_complete == False)
+check("ping-pong loop has valid target", anim3.hasValidTarget() == True)
+
+
+# --- Test 5: complete() on ping-pong returns to start value ---
+sprite4 = mcrfpy.Sprite(pos=(50, 0))
+scene.children.append(sprite4)
+anim4 = sprite4.animate("x", 200.0, 1.0, mcrfpy.Easing.PING_PONG)
+
+# Step partway through
+for _ in range(3):
+    mcrfpy.step(0.1)
+
+# Now complete - should return to start (50), not go to target (200)
+anim4.complete()
+completed_x = sprite4.x
+check(f"complete() returns to start ({completed_x:.1f})", abs(completed_x - 50.0) < 5.0)
+
+
+# --- Test 6: stop() on ping-pong freezes at current value (no jump) ---
+sprite5 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite5)
+anim5 = sprite5.animate("x", 100.0, 1.0, mcrfpy.Easing.PING_PONG_SMOOTH)
+
+# Step to ~midpoint
+for _ in range(5):
+    mcrfpy.step(0.1)
+
+pre_stop_x = sprite5.x
+anim5.stop()
+
+# Step more - value shouldn't change
+for _ in range(5):
+    mcrfpy.step(0.1)
+
+post_stop_x = sprite5.x
+check(f"stop() freezes value ({pre_stop_x:.1f} == {post_stop_x:.1f})",
+      abs(pre_stop_x - post_stop_x) < 1.0)
+
+
+# --- Test 7: Callback receives start value for ping-pong ---
+callback_values = []
+def on_complete(target, prop, value):
+    callback_values.append(value)
+
+sprite6 = mcrfpy.Sprite(pos=(10, 0))
+scene.children.append(sprite6)
+anim6 = sprite6.animate("x", 300.0, 0.5, mcrfpy.Easing.PING_PONG, callback=on_complete)
+
+# Step to completion
+for _ in range(10):
+    mcrfpy.step(0.1)
+
+check("callback was triggered", len(callback_values) == 1)
+if callback_values:
+    # Callback value should be near start value (10), not target (300)
+    check(f"callback value ({callback_values[0]:.1f}) is near start (10)",
+          abs(callback_values[0] - 10.0) < 5.0)
+
+
+# --- Test 8: EaseInOut ping-pong (sin^2) is smooth at boundaries ---
+sprite7 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite7)
+anim7 = sprite7.animate("x", 100.0, 1.0, mcrfpy.Easing.PING_PONG_EASE_IN_OUT)
+
+# Capture values at several timesteps
+values = []
+for _ in range(10):
+    mcrfpy.step(0.1)
+    values.append(sprite7.x)
+
+# First value should be small (accelerating from 0)
+check(f"easeInOut starts slow ({values[0]:.1f} < 30)", values[0] < 30.0)
+# Middle values should be larger
+check(f"easeInOut peaks in middle ({max(values):.1f} > 70)", max(values) > 70.0)
+# Last value should be near 0 again
+check(f"easeInOut returns to start ({values[-1]:.1f} < 10)", values[-1] < 10.0)
+
+
+# --- Test 9: Legacy string names work for ping-pong ---
+sprite8 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite8)
+anim8 = sprite8.animate("x", 100.0, 0.5, "pingPong")
+check("legacy string 'pingPong' works", anim8 is not None)
+
+for _ in range(10):
+    mcrfpy.step(0.1)
+check("legacy string anim completes", anim8.is_complete == True)
+check(f"legacy string returns to start ({sprite8.x:.1f})", abs(sprite8.x) < 5.0)
+
+
+# --- Test 10: Standard easing complete() is unaffected (regression) ---
+sprite9 = mcrfpy.Sprite(pos=(0, 0))
+scene.children.append(sprite9)
+anim9 = sprite9.animate("x", 500.0, 1.0, mcrfpy.Easing.EASE_IN_OUT)
+
+# Step partway
+for _ in range(3):
+    mcrfpy.step(0.1)
+
+anim9.complete()
+check(f"standard easing complete() goes to target ({sprite9.x:.1f})",
+      abs(sprite9.x - 500.0) < 5.0)
+
+
+# --- Test 11: Animation constructor with ping-pong easing ---
+anim10 = mcrfpy.Animation("x", 100.0, 1.0, mcrfpy.Easing.PING_PONG, loop=True)
+check("Animation constructor with PING_PONG", anim10 is not None)
+check("Animation constructor loop=True", anim10.is_looping == True)
+
+
+# --- Summary ---
+if PASS:
+    print("PASS")
+    sys.exit(0)
+else:
+    print("FAIL")
+    sys.exit(1)