rthythm_archor_game/docs/decisions.md

# Migration Decisions

## 2026-07-06 第八轮：视差语义定案（远景天幕，夕阳恒在画面内）

策划澄清视差意图：背景是**远景天幕**，夕阳要时刻在画面内——即背景应
大比例**跟随相机**（远景几乎不动的错觉），而非此前理解的"背景比世界慢
一点"。此前 0.92/0.8 的参数把背景几乎钉在世界上，方向整个反了，这才是
连续几轮"看不出视差"的真因。

1. **参数**：`PARALLAX_SCROLL_SCALE := 0.2`（背景仅以 0.2 倍速随世界滚动，
   80% 跟随相机）；`PARALLAX_ANCHOR_X := 1734.5`（让夕阳——原画 x≈760、
   世界 x≈1656——在出生点镜头可见中心 1340.8 恰好居中）。
2. **验算+截图验证**：相机可见中心全程 [1340.8, 2753.2]，夕阳屏幕位置从
   正中缓移到左 282px，始终在画面内（含光晕）；两端背景覆盖充足
   （极左窗⊂[581.5,2882.5]、极右窗⊂[1711.5,4012.5]）。窗口化实测四点
   截图确认：出生点夕阳居中、中段/封门处缓移仍在画面中央区域，未来
   相位（红色天幕）同样成立；世界物件大幅滚动 vs 天幕缓动的对比即
   视差观感本体。
3. **已知取舍加剧说明**：天幕语义下步道砖（烙在原画里）随镜头大幅跟随
   （奔跑时脚下滑动 176px/s）——单张烙死图的固有代价；美术把"近景步道"
   拆成独立 1:1 层后即可消除，其余层保持现参数。
4. 可视化验证配方（复用）：manage_scene=false + 手动挂 main.tscn +
   start_game()，Title 态直接 _set_state 不行（树暂停 + 标题屏不透明底色）。

## 2026-07-06 第七轮修复（玩家与敌人重叠：冲刺穿人收尾排斥）

策划确认：冲刺穿人机制保留，其余时间玩家不得与小怪/Boss 重叠。

1. **调查结论**：身体碰撞矩阵完整且实测有效（玩家 layer32/mask65，敌人
   layer64/mask33，平移互撞精确挡在半宽和 19px）。重叠的真实来源是
   dash_through 的收尾策略：落点嵌在敌人体内时，恢复碰撞的逻辑"干等分离"
   （07-04 定案，防止嵌入恢复被反推回入口侧）——嵌着就无限期保持幽灵态，
   玩家可长期站在敌人身体里；期间敌人 AI 还会照常向玩家中心走位，把重叠
   "续命"。叠加事实：Godot 的 move_and_slide 对已重叠的双方永不主动分离
   （safe_margin 0.001），所以一旦嵌入只能靠显式排斥。
2. **修复**：MotionExecutor 记录冲刺方向；`_try_restore_collision` 嵌入时
   不再干等，每物理帧沿冲刺方向 `move_and_collide` 推 4px（240px/s，快于
   小怪追击 120px/s），顶到边界墙推不动则反向从入口侧退出；推清后恢复
   碰撞。幽灵掩码只剩 world 位，排斥不可能进入地形。"从远侧穿出"的
   07-04 手感语义保留；cancel 的非物理帧即时恢复路径不变（有测试钉）。
3. **不动的部分**：敌人互相不碰撞（minion/boss mask 无 bit64，成群穿插是
   现状设计）；小怪尸体在死亡动画期间仍挡路（存量怪癖）；Boss 战前
   combat_enabled=false 非实体是有意豁免（test_level1_melee_contact 钉）。
4. 契约测试 test_dash_overlap_separation：嵌入落点 45 帧内推出+恢复碰撞+
   从远侧穿出+间距 ≥ 半宽和；干净落点行为与旧版一致。

## 2026-07-06 第六轮修复（Boss→玩家击退 / 视差加强重启）

**语义澄清**：策划三轮反馈的"Boss 击退"实指 **Boss 攻击玩家时对玩家的击退**
（第三~五轮修的"玩家击退 Boss"方向保留不回退）。

1. **Boss→玩家击退不可见的三个根因**：①Boss 近战沿用默认基准 120，普通
   连段倍率仅 0.4/0.5 → 滑行 2~3px（重击也只 20~37px）；②敌方弹丸基准击退
   恒为 (0,0)（actors_container 只给敌弹注 speed），Boss 未来相位只用远程 →
   整相位击退数学上为零（.tres 里的 0.3/0.5 倍率是死数值）；③相机 1:1 跟随
   玩家——玩家被击退时自己在屏幕上不动，只有背景平移，小位移完全无感。
2. **修复**：boss.tscn DamageEmitter 覆写 `base_knockback = (360, 304.056)`
   （初速 ×3 = 距离 ×9）：连段 20/32px、重击 190/341px；敌方弹丸生成时注入
   `base_knockback = (360, 0)`（不击飞）：Boss 射击 11~32px、女巫 8~15px，
   强弱势归零规则照常生效。Boss 恒强势（is_strong_in_current_time_phase
   恒 true），玩家 Hitstun 0.4s 内不能起手/移动，滑行不受自身动作干扰。
   调参 knob：boss.tscn 的 base_knockback 一处 + actors_container.gd 注入值。
3. **视差加强重启**：0.92 时代偏移峰值仅 ±56px、实战镜头段 ±20px，肉眼难辨
   （策划"看不出视差"两轮反馈的真因；上一轮误判为"脚下打滑"而回退）。现
   `PARALLAX_SCROLL_SCALE := 0.8`，峰值 ±141px、实战段 ±60px。已知取舍：
   步道砖烙在原画里会随镜头轻微滑动（0.8 下奔跑时约 44px/s），策划若不接受
   只能等美术拆层（无伤视差的唯一解，接线半小时）。

## 2026-07-06 第五轮修复（击退被反向突进吃掉 / 视差回退）

1. **Boss 实战零击退的真凶：自己的下一拍动作**。裸场景击退管线全通过，但
   真实 stage 里 Boss 被击退 3 帧后就照常起手攻击（attack 态还冻结摩擦衰减），
   随后动作自带的突进位移接管 velocity 以 -375px/s 冲回玩家——实测净位移
   **-24px**（比不击退还近）。修复：**趔趄门禁**——击退残速期
   `can_start_enemy_action` 返回 false（EnemyActionDriver 的 BT/谱面双路径
   都走此钩子），滑行完整播完 AI 才恢复；小怪加同款钩子。Boss 受击链强制
   撤退豁免：`_trigger_hit_chain_escape` 先 `clear_knockback_stray()`（新增
   motor 公开方法）再起手 boss_retreat_dash，否则 4 连击逃脱被门禁拦死。
   真实 stage 探针验证：位移 -24px → **+132px**（≈理论 129.6）。
2. **单层微视差回退**。可行走步道砖烙在关卡原画里，整图 0.92 倍速 =
   角色脚下地砖打滑（策划反馈"视差有问题"即此）。逐像素核查后确认横向
   分层缝也不可行：油灯底座 y495-520、栅栏柱脚 y485-495、锚徽 y495-555、
   步道面 y495-550 相互咬合，任何水平缝都会把显眼物件剪成两截随视差错位；
   左右边界石墙纵贯全高更无法归层。结论：**单张烙死的图做不了无伤视差**，
   已回退到背景钉死，契约改为"背景不得随相机移动"。真视差待美术按
   "天空/远景海船/中景码头道具/近景步道"拆层出带透明通道的 PNG（宽度均
   ≥2301+视差余量），接线约半小时（每层 Sprite2D + 相机可见中心 × 系数，
   勿用 Parallax2D——历史上因 CanvasModulate/wipe 兼容性移除过）。

## 2026-07-05 第四轮修复（Boss 击退加码 ×9 / 小怪击退修复 / 单层微视差）

1. **Boss 击退距离 ×3 → ×9**：首轮 ×3（滑行 43px 级）试玩仍嫌短，策划要求再
   ×3。`boss.knockback_distance_taken_mult()` 3.0→9.0（初速 ×3）。斩波 Lv1
   击退 Boss ≈130px、下砸 ≈634px；嫌多嫌少改这一个返回值即可。
2. **小怪击退修复（结构 bug，与 Boss 同源）**：minion.tscn 挂着 MovementMotor
   但 minion.gd 零引用——击退初速写入后下一帧就被 AI 接管/清零，且 motor 的
   摩擦衰减和假高度积分从不执行。修复：新增 movement_motor 成员；
   handle_air_time 无条件委托 motor（boss 同款）；handle_movement 在相位切换
   hold **之后**加击退残速早退（换相位定身优先）。顺带修掉隐藏 bug：垂直击退
   曾令小怪 ground_state 永久卡 Airborne，从此 allowed_ground_states 拒绝一切
   出招——现在假高度正常积分、落地复位 Grounded。小怪不加距离倍率（基准
   15~70px 滑行），策划试玩后如需加码再走 knockback_distance_taken_mult 钩子。
3. **关卡背景单层微视差**：ground_background.gd 新增 _process——ArtLayer.x =
   基准 + (相机可见中心 − 2047) × 0.08，即背景水平速度为相机的 0.92 倍
   （PARALLAX_SCROLL_SCALE）。锚点 2047 = GroundAnchor = battle_center =
   贴图中心；极限位移 ±56.5px，已验算两端不露边（顺带修掉了原有的极右
   16.5px 潜在露边）。用 get_screen_center_position()（含 limit 夹取）而非
   camera.global_position，玩家贴墙时背景不跟滑；无相机（headless/菜单）
   保持原位。手写每帧位移而非 Parallax2D：历史上 Parallax2D 因
   CanvasModulate/wipe 兼容性已被移除过（见下方历史条目）。真·多层视差
   （天空/远景/近景分速度）等美术拆层素材到位后再升级。
4. **修复存量 flake**：test_rhythm_feedback_and_move_list 的特殊拍断言依赖
   "启动后 0.46s 内跑到检查点"（RhythmManager 墙钟自启动，_upcoming_beat_index
   走实时钟），启动稍慢即越过第 1 拍。按测试纪律钉停时钟（stop_manager），
   走确定性 _last_beat_index 兜底。6 连跑验证。
5. 契约测试 test_round4_fixes 钉住小怪水平滑行/残速自清/垂直击退落地恢复、
   视差公式与无相机兜底；Boss ×9 更新在 test_round3_fixes。

## 2026-07-05 第三轮修复（标题背景重组 / 判定字样 1s 消失 / Boss 击退 ×3）

1. **标题画面重组**：背景弃用烙有 Logo 的整图（start_background_past/future），
   改用无 Logo 的干净关卡原画 `assets/art/ground/past/past.png` 与
   `future/future.png`（与关卡内背景同资产），Logo 由独立悬浮 TextureRect
   （`TITLE_LOGO_RECT` = 390,140,616×300，MOUSE_FILTER_IGNORE）叠加。背景轮换
   周期改为策划口径"2 秒为单位渐入切换"：`TITLE_BG_HOLD_SECONDS` 2.8→2.0、
   `TITLE_BG_FADE_SECONDS` 1.6→0.8。渐变期间 Logo/菜单固定，顶部重叠感消除。
   难度选择页同步换干净未来原画 + 悬浮 Logo。双背景节点名与 `_title_bg_tween`
   变量契约保持不变（test_title_music_and_background 无需改动）。
2. **判定字样 1 秒自动消失**：rhythm_track 新增 `JUDGEMENT_VISIBLE_SECONDS=1.0`
   倒计时；每次 `_show_judgement_art`（普通判定/锚点 held/TIME SHIFT 三条路径）
   重置计时（"顶替"语义），到点把 JudgementArt/JudgementLabel 一并隐藏。倒计时
   期间不动 modulate/text/scale，与脉冲动画及判定色互不干扰。
3. **Boss 击退距离 ×3**：调查发现 Boss（水平）击退位移实际恒为 0——boss.gd
   `handle_movement()` 每物理帧无条件 `velocity.x = 0.0`，击退初速活不过一帧
   （headless 实测 61 帧位移 0.00px）。修复：MovementMotor 暴露
   `has_knockback_stray()`，Boss 在击退残速期跳过清零、交给 480px/s² 摩擦自然
   衰减（与玩家同路径，不用被 test_boss_integration 禁止的本地计时器 hack）。
   距离 ×3 通过受击方鸭子钩子 `knockback_distance_taken_mult()=3.0` 实现，
   CombatManager 按 距离∝初速² 换算为初速 ×√3；只放大水平滑行，击飞不变。
   实测 120 初速滑行 14.4px→43.3px。小怪存在同类清零问题（minion.gd AI 每帧
   接管 velocity.x），策划未提，本轮未动。
4. 契约测试 test_round3_fixes 钉住以上全部行为（背景资产路径、2s/0.8s 常量、
   悬浮 Logo 几何与鼠标穿透、判定 1s 消失+顶替重置、Boss 击退倍率与残速存活）。

## 2026-07-05 第二轮需求落地（剑雨放大 / 敌弹降速 / 菜单组件化 / 结算重做 / 受击朝向修复）

依据策划当日九条答复的最终口径：

1. **剑雨放大一倍（伤害不变）**：6 个 jian_yu .tres 的 `range` 140→280（三级判定
   仍相同）；落剑视觉 strike_count `1+level`→`2*(1+level)`（4/6/8 把）、spread
   `90+40*level`→`120+40*level`（Lv3 最远落点 40+240=280 恰与新判定对齐，顺带修复
   旧版"视觉铺 250px 但判定只有 140px"的空气剑）；BLADE_RAIN_TILE_SPECS 四条目
   scale 0.5→1.0（raindrop 跟随）。damage_mult/base_cost 一字未动。
   test_blade_rain_alignment 的 Lv3 数量断言 4→8。
2. **敌弹降速 80%（斩波不变）**：actors_container.gd 新增
   `ENEMY_PROJECTILE_SPEED := 416.0`（520×0.8），非玩家阵营弹丸生成时覆写 speed；
   玩家弹保持 player_projectile.gd 默认 520。销毁按累计飞行距离，降速不缩射程。
3. **受击朝向修复（策划定案：保持受击前朝向）**：双根因双修——
   ① combat_manager._apply_knockback 按受击者与 result["from"]（emitter 位置）的
   x 差把水平击退方向化为"背离攻击者"（dx=0 或缺 from 保留旧 +X）；result dict
   里的 knockback 数值保持 resolver 原值，纯数值契约测试不受影响。
   ② movement_motor 新增 `_knockback_stray_active` 标记：apply_knockback 置位、
   残速衰减到 0 或自主移动接管时清除；set_heading 在标记存活或 life_state !=
   Alive 时不改写 heading。玩家/敌人同语义（受击不转身）。
4. **菜单组件化（废弃整图+透明热区）**：新素材套件入库 assets/ui/menu2/
   （面板 panel_tall + 按钮底两态 button_base_normal/hover + 文字贴图 13 张 +
   Logo title_logo），中文字体 assets/fonts/fzzdhjw.ttf。game_flow_manager 全部
   界面改为"面板 + StyleBoxTexture 双态按钮 + 文字贴图/字体"拼装：标题（Logo+
   三键+当前难度页脚）、难度选择（简单/普通/困难+开始/回标题+页脚，选中=高亮橙
   框）、暂停/确认框/胜负 splash（NinePatch 面板；确认框用 确认/取消 贴图）、
   结算（整面板+游戏结算标题字）。按钮保持 Button 类型 + 旧点击矩形兼容坐标测试；
   过去/未来场景背景轮换保留。素材里的"结束游戏"按策划答复弃用。
5. **结算重做**：统计标签中文化（最大连击/完美/良好/勉强/失误/锚点成功/相位
   切换，fzzdhjw 字体渲染）；RANK 只留等级（"RANK S"，去掉 "(83/100)" 分数），
   失败仍不显示 RANK。胜负停留时间 ×3：VICTORY_SCREEN_DELAY 1.2→3.6s、
   DEFEAT_SCREEN_DELAY 1.6→4.8s；保留两段式（胜负 splash → 查看结算 → 结算）。
6. **胜负合成音效（策划定案：合成音，不引音频文件）**：SfxManager 新增
   &"victory"（C5-E5-G5-C6 上行琶音 1.2s）与 &"defeat"（G4-Eb4-C4-G3 分立下行
   1.3s，与 &"death" 滑音区分）；订阅 EventBus.flow_state_changed，进入
   Victory/Defeat 态时播放（voice 继承 PROCESS_MODE_ALWAYS，暂停树可发声）；
   玩家死亡瞬间的 &"death" 保留叠加。
7. 新契约测试 test_round2_changes（剑雨数值、敌/我弹速、击退方向、朝向门禁、
   延迟常量、结算中文与 RANK 格式、难度页脚联动）。
8. 顺带修复的存量测试问题：①四个对难度敏感的测试（startup_fix / time_phase_adapter /
   ui_animation_regression / v2_core_contracts）此前隐性依赖 menu 测试残留在
   settings.cfg 的 easy 难度，现已显式钉 easy；②三处过时断言改到现口径——相位强势
   倍率实为 ×1.4（资源 07-04 校准）、谱面预告标记已有意停用（钉住"不生成"）、combo
   HUD 脉冲断言改抓命名槽位 Slot1；③test_stage4_movement_physics 的固定秒数等待
   会被 ANCHOR_ACTIVE 起手拉伸打败（偶发 flake），改为物理帧轮询。

## 2026-07-05 new1/new2/new3 需求落地（判定门控 / 左侧出生 / 怪物与 Boss 行为）

依据 docs/new1-3.md 与策划当日答疑的最终口径（new1 原文的"零代价无效输入"
已被策划改为"MISS+锁定"混合方案）：

1. **判定门控（new1 定案）**：RhythmManager 新增 `gate_judged_input` /
   `is_input_locked`（`input_lockout_seconds` 0.5、`consumed_repeat_grace` 1）。
   规则：每个节奏点只能被一次有效输入消耗；同拍第二次按键按双击容错忽略；
   第三次（或超出 BAD 窗的空按）判 MISS——保留原惩罚（无动作、清连击、四拍
   槽写 ∅）并触发 0.5s 输入锁定，锁定期间按键完全无效（不判定、不留痕、不
   刷新锁定）。纯判定接口 judge/get_rating_for_time 保持无副作用；门控只作
   用于**实时判定**的输入（_ensure_judged 打 `live` 标记），测试/AI 的预置
   判定原样绕过。接入点：ActionController.submit_intent 主路径 +
   两个蓄力施放路径。锁定横跨时间锚点拍 = 锚点必破（相位切换），设计确认。
   test_player_combo_input 顺带修复：每次按键前把时钟钉到新拍心，替代旧的
   墙钟判定（~20% flake 消除）。新测试 test_input_gate。
2. **出生点左移（new2）**：stage.tscn 玩家 (2047,560)→(1180,560)，相机初始
   (1180,395)；开场需向右推进约 1000px 才遇预置近战怪（2200 不变，策划确认
   该段路用于熟悉操作）。LevelDirector 的战斗中心/增援锚点不变。标题固定+
   背景轮播本就已实现，未改动。基线测试（x1_visual_baseline /
   rhythm_ui_layout / boss_integration / level1_melee_contact /
   minion_phase_system）中依赖旧出生点的断言改为按门线/停步距离取位。
3. **伤害体系（new3 定案）**：保留"基础攻击 × 相位倍率"。近战小怪基础攻击
   翻倍 25→50（LevelDirector 按 MinionBehavior.role 配置 emitter.damage，
   远程保持 25）；Boss 近战招式倍率翻倍（combo 0.8/0.9→1.6/1.8；重击保守
   放大 combo_3 1.4→2.2、lunging_stab 2.0→3.0，未按字面 ×2 以免单跳 120），
   Boss 远程倍率下调 shoot 0.6→0.4（30×0.4=12 恰合 new3 推荐）、2way
   0.7→0.45。
4. **距离参数（new3）**：近战怪警戒 420→360、停步 110→120、出手距离
   150→120、攻击判定 range 58~74→130（前方 reach≈140）；远程怪危险距离
   150→220、后撤 190→220、后撤完毕按拍停顿 1 拍；**射程上限压到视距内**
   （攻击距离 430→450 ≤ 相机半宽 460——绝不屏幕外开火，new3 的 720 被策划
   否决）。Boss melee_distance 135→180、ranged 260→360、dash 360→460。
5. **远程怪受击脱离（策划定案，取代 new3 §5.5 的单次受击）**：连续受击 4 次
   （2s 链窗）触发闪烁无敌 0.4s + 跳跃形式脱离（escape_speed_scale 3.2；
   minion.gd 的 approach_direction 钳制放宽到 ±4）；无敌走
   FrameCollisionDriver.damage_receiver_enabled（驱动器每帧重申矩阵，直接改
   Area2D 会被覆盖）；3s 冷却防连续触发；贴墙时沿用穿过玩家身位的反向跳。
6. **Boss 霸体（策划定案，取代 new3 §6.5 韧性系统——明确不做韧性）**：
   CombatResolver 新增受击方 `shrugs_off_hit(action)` 钩子；Boss 对
   base_cost≤0 的攻击恒霸体（伤害照常、打断与击退取消），耗能技能可压制。
   所有耗能技能补上击退：dash_slash 1.5、combo_finisher 2.0、ground_smash
   2.2（保留原 y1.8 击飞）、zhan_bo 1.0/1.3/1.6、jian_yu 0.8/y0.6；玩家弹丸
   在 ActorsContainer 注入 base_knockback(120,304)（原为零）。保留"被连打
   4 次后撤逃脱"作为防贴脸兜底。resolve_knockback 顺带修复为跟随伤害判定
   通道（good 0.85），对齐 test_combat_manager_resolvers 既有契约。
7. **Boss 相位行为（new3 §6.4/6.7）**：远程相位被近身（≤240px）优先
   boss_retreat_dash 拉开（后撤无伤害、8 拍冷却）；相位切换后停顿 1 拍再
   决策（以总线最后拍号为基准，兼容测试合成拍号）。stage.tscn 的 Boss
   stationary=true 保持——那是战前木桩状态，BossRoomGate 反锁时已会释放。
   新测试 test_new3_enemy_rules（霸体规则/按职责基础攻击/受击脱离）。

## 2026-07-04 playtest pass 2 (dash pierce / anchor presentation / radial phase wipe)

1. **Dash-through actually pierces now.** Two compounding defects: (a) action
   displacement speed was computed over the full action length while the
   motion only runs from Active start to action end, so every action
   under-travelled by the startup fraction — the 260px dash realized ~195px
   and frequently ENDED inside the boss; (b) the collision mask snapped back
   the moment the action finished, so ending overlapped meant depenetration
   shoved the player back out the entry side ("did not pierce").
   Fixes: `_action_motion_speed` divides by (action_beats - startup_beats);
   MotionExecutor ghosts BOTH directions during dash_through (strips
   player_body|enemy_body bits from mask AND layer so neither side's
   move_and_slide recovery can shove anyone), and restores collision
   deferred — each physics frame it shape-queries the ghosted body layers
   and only snaps back once clear of overlap. Outside physics frames
   (headless tests) restore is immediate, keeping the existing
   test_stage4_movement_physics contract green.
2. **Time anchor presentation follows the upgrade semantics.** The mirrored
   red pair converging every anchor beat read as "recolored beat balls",
   and at high streak tiers (interval 1) it doubled screen elements. Now:
   the beat movers THEMSELVES turn anchor-red when the beat they converge on
   is an anchor (screen element count never exceeds the rhythm grid).
   Follow-up: the extra "herald" ball that parked above the center emblem was
   judged redundant in playtest (the recolored movers + the HUD "ANCHOR Nb"
   countdown carry the information) and was removed entirely — time anchors
   add zero elements to the track. Held/broken feedback unchanged.
3. **Phase switch is a player-centered radial wipe.** Scene tint now lives
   solely on the CanvasModulate (stronger: past warm 1.0/0.94/0.82, future
   cool 0.55/0.72/1.0; the color-mapped ground reads as the other map). On
   time_phase_changed the world gets the NEW tint instantly and a fullscreen
   blend_mul shader multiplies everything OUTSIDE an expanding circle
   (centered on the player, radius 0 → screen diagonal in 0.5s) by
   old_tint/new_tint — the old scene visibly dissolves outward from the
   player, with a bright rim at the wavefront. Works symmetrically in both
   switch directions; the wipe center follows the player each frame.

## 2026-07-04 action feel pass (mirroring / air slam / dash derive / charge gauge / dummy boss)

Fixes driven by playtest feedback against the player_tagged author sheets:

1. **Blade wave cast mirroring.** zhan_bo has no displacement and no left/right
   tag, so the body never turned while the projectile aimed at the nearest
   boss. `_play_action_animation` now faces projectile actions
   (`hit_type == projectile` or `projectile` tag) toward
   `projectile_direction()`; the whole Visual (body + FX overlay) mirrors
   with heading as usual.
2. **Air combo is a ground slam.** The author's 12-Aerial Combo sheets are
   byte-identical to 13-Plunging Strike (PREP / SWING START / FALLING [LOOP] /
   LAND + FX2/3/4): the move is a forward slam, not an in-air slash. atk_air
   gained the falling loop segment + FX3 hold; both atk_air and plunge_start
   now arm `_pending_air_slam_land` at active start — the falling pose holds
   until touchdown, then a shared `air_slam_land` animation (land.png 6f +
   FX4) plays. FX overlay offsets follow the author's bottom-right anchor
   rule `offset = (64 - cell_w, -cell_h)` → FX4 (135x166) = (-71, -166).
   air_attack_l/r data: move_mult_y 0.2 → -1.6, active 0.5 / recovery 0.5.
3. **[A][sp] derive beats the A-charge.** With hold_threshold at 0.25 beats
   (0.125s @120bpm), beat-cadenced [A] then [SP] with A still held had already
   entered Charging, so SP was shelved and the A release cast blade rain.
   New rule in ActionController.submit_intent: a pressed SP while an
   on_release charge hold (A/D) is armed or charging breaks the charge and
   falls through to normal resolution — the four-slot window still holds [A],
   so [A][SP] resolves the dash (dash_through pierces the boss and hits while
   passing). S-charge (on_secondary_key) is untouched.
4. **Blade rain composite.** Falling blades now fall for exactly
   BLADE_RAIN_DROP_FALL_TIME (0.24s @1900px/s) and vanish at ground contact
   as the landing tile starts (its first frames carry the streak + impact);
   tiles are bottom-anchored to the ground line via per-sheet cell_height,
   uniform 0.5 scale, spread grows with charge level (2/3/4 strikes).
5. **Charge gauge = cast level.** ChargeComponent's private 1.1s ramp had
   nothing to do with the beat-quantized cast level in ActionController.
   ActionController now exposes `charge_state()` (MAX_CHARGE_LEVEL 3,
   progress_units 0..max-1) as the single source; the gauge renders
   level-space (ready == top level), pulses the overlay on level-up, and the
   HUD shows "CHARGE LV n / 3" with per-level fill colors. Legacy 1.1s ramp
   remains only as a standalone fallback.
6. **Dummy boss for testing.** Boss export `stationary` (attacks but never
   displaces: no BT dash/retreat — replaced with ranged pressure — no action
   motion, no hit-chain escape). Enabled on the Stage instance only;
   boss.tscn keeps mobile defaults so behavior-tree contract tests still
   exercise retreat/escape (the point-blank test explicitly un-sets it).

## 2026-07-04 time anchor / dual time phase feature pass

Implemented the full AnchorV1.0 chapter 10-12/17/20 feature set following the
incremental plan in `Fighting_Rthythm_game/docs/时间锚点与双相位架构修改方案.md`
(all names below use its reserved terms: `time_anchor` / `time_phase` /
`attack_buff` / `streak`):

- **New autoloads** (registered after CombatManager): `TimePhaseManager`
  (sole writer of `current_time_phase`, broadcasts `time_phase_changed`) and
  `TimeAnchorSystem` (schedules chart-explicit + periodic anchors, resolves
  held/broken from `judgement_made` facts only, routes `force_time_phase`).
  Periodic candidates are computed lazily (origin + current streak tier) and
  lock when they enter the 2-beat lead window; explicit chart anchors win
  same-beat collisions and restart the periodic count.
- **EventBus** gained `time_phase_changed` / `time_anchor_scheduled` /
  `time_anchor_resolved` / `streak_changed` / `attack_buff_changed`.
  `judgement_made(quality, offset_ms, beat_index)` was already extended
  during migration (7.1-A), so everything here is pure increment.
- **EffectContainer** two increments only: stack-aware aggregation for add
  modifiers (`value x stacks`; all pre-existing resources are max_stacks 1,
  audited by test_effect_container) and `set_effect_stacks` (plus a small
  `effect_stacks` reader). Resolvers/CombatManager/RhythmManager untouched.
- **Player** gained `StreakCounter` (+1 on skill_executed, zero on miss /
  chart_reset) and `AttackBuffComponent` (stack storage IS the
  `effect_time_anchor_attack_buff.tres` Effect instance: +10% damage_mult per
  stack, cap 20, halved floor on every actual phase switch, zeroed on
  chart_reset). Damage rides the existing buffs multiplier slot in
  `resolve_damage` — the design formula 1 + 0.10 x stacks emerges from the
  stack-aware aggregation.
- **Boss** gained `TimePhaseAdapter` with the PastStrong profile
  (`resources/time_phase/profile_past_strong_enemy.tres` — past: dmg x1.2 /
  taken x0.8, future: x0.7 / x1.3 via `effect_tp_*` resources; the
  FutureStrong mirror profile exists for future enemies). Damage-taken
  multipliers ride DefenseModifier entries; both phases share all collision.
- **Chart layer**: `ChartEvent.time_phase_mask` (+`matches_time_phase`),
  `ChartTrack.time_phase_mask` (authoring default pushed onto `both` events
  at load), `BeatChart.initial_time_phase`, ChartRunner trigger-time final
  ruling (skipped events are marked triggered and never re-dispatched) and
  initial-phase application on ready/reset. stage9_boss_duel gained a
  time_anchor track (beats 8 / 40).
- **Dual music layers**: `AudioLayerController` (scenes/audio/) runs two
  always-synced players seeded from `RhythmManager.song_position`, crossfades
  volumes on phase switch (0.35s), drift-corrects the *presentation* players
  only (loop-wrap aware), and mutes the clock stream. Placeholder assets:
  both layers use ev_past1.mp3; the future layer goes through a runtime low-pass
  bus so the switch is audible until a real Future loop lands.
- **Presentation placeholders per request**: the second map is ground.png
  color-mapped (Stage tints the ground sprite + a CanvasModulate, warm past /
  cool future, 0.35s tween + white flash under the UI layer); the time anchor
  ball is yellow_ball.png color-mapped crimson in RhythmTrack (mirrored pair
  converging on the center, grows near the hit point, held → green lock
  flash "ANCHOR HELD", broken → magenta "TIME SHIFT!").
- **HUD**: TimePhaseHud (phase name + next-anchor countdown, buff stacks
  /20 with percent, streak) and DebugPanel lines for time phase state and
  armed/last-resolved anchors.
- **Tooling/tests**: `tools/time_anchor_chart_tool.gd` (validate / generate /
  simulate) and seven new SceneTree tests (`test_time_phase_manager`,
  `test_time_anchor_resolution`, `test_time_anchor_scheduling`,
  `test_streak_counter`, `test_attack_buff`, `test_time_phase_adapter`,
  `test_chart_time_phase_mask`). No Godot binary is available on this
  machine, so the suite is authored but not yet executed locally.

Open tuning items deferred (doc chapter 12): anchor-specific window, streak
clear on hurt, on_break punishment effects, conditional anchors (v1.5).

## 2026-07-03 body collision audit

Phase 0 keeps the base physics layer names from the migration manual:
`world`, `player_hurtbox`, `enemy_hurtbox`, `player_hitbox`, and `enemy_hitbox`.

The source project still uses root body collision to let the player and boss block each other:
the player body is on layer 2 with mask 5, while the boss body is on layer 4 with mask 3.
To preserve that feel without mixing body blocking into hurtbox or hitbox layers, the target
project reserves layer 6 as `player_body` and layer 7 as `enemy_body`.

## 2026-07-03 phase 4 character asset migration

Phase 4 copies character art only from the curated `tmp/new` source folders:
`player_tagged` is migrated to `res://assets/art/characters/player/`, and `boss_tagged`
is migrated to `res://assets/art/characters/boss/`. File names are normalized to ASCII
snake_case before animation paths are authored.

The player package README is preserved as `credits_blair_ceradsky.txt`; the package is
CC-BY 4.0 and must credit Blair Ceradsky / @MookaTheCaveman. The boss folder still has
no license file in the source material, so boss art is a development asset until the
license is identified and added.

The old jump-height test is superseded by a no-free-movement/no-jump-input regression:
player movement in this migration comes from ActionData-driven rhythm actions only.

## 2026-07-03 post-migration bug-fix pass

A full audit against `AnchorV1.0.md`, the migration plan/manual, and the character/boss
design doc fixed the following migration defects (tests updated in the same pass):

1. Energy scale: player max energy was 10 while skills cost 15-50, so no skill could
   ever be paid for. Player/EnergyComponent max is now 100 and the energy bar fills
   proportionally.
2. Melee reach: all player melee ActionData had `range = 0`, leaving a 48px centered
   hitbox that body-blocking made unreachable. Every melee action now carries a range.
3. Projectile teams: the shared projectile scene was hard-wired to enemy-hitbox layer /
   player-hurtbox mask, so the player's blade wave hit the player and never the boss.
   `projectile_requested` now carries a context Dictionary (team, action, judgement,
   range); ActorsContainer assigns collision layers per team and injects the ActionData
   and judgement so damage multipliers resolve. Player gained muzzle spawn methods;
   the boss muzzle height was lowered to 55 so bullets actually cross the player hurtbox.
4. Super armor: HealthComponent entered Hitstun on every damaging hit regardless of
   `interrupts`; it now respects the defense resolution (death still always applies).
5. Boss behavior tree: retreat no longer has top priority at melee range (combo first,
   2-way shot punish when melee is on cooldown, retreat only after both), the ranged
   cycle no longer bypasses the 2-way cooldown, and beyond dash range the boss closes
   in instead of shooting forever. Hit-chain escape now needs 4 hits, has a 4s cooldown
   and only fires while grounded. Chart events take priority: an upcoming chart event
   postpones BT decisions and a triggering chart event overrides a BT action.
6. Boss presentation: MotionExecutor is cancelled on action end (no more sliding across
   the arena), animation speed_scale is aligned to the action's beat length, and the
   boss no longer turns to track the player mid-action.
7. Charge levels: level was measured from the initial key press (always level 3);
   it is now measured from time spent in the Charging phase, quantized by
   `charge_level_beats` (1 beat per level). Holding A/D during a chain-cancelled combo
   step now arms the charge gate too.
8. Combo HUD: enemy ComboWindows no longer broadcast to the EventBus, so the player's
   four-slot HUD is not wiped whenever the boss is interrupted.
9. Direction semantics: displacement direction now follows the left/right action tags
   (mirror pairs) and falls back to the current heading for forward actions (W launcher
   no longer forces the player to face right); plunging strike now actually drives the
   fake-height fall (negative move_mult_y maps to height_speed while airborne).
10. Player presentation: hit-stun and death now play (manual sheet animations from
    14_hit_stun / 15_death), the plunge has its falling loop, and the charge FX overlay
    uses the real charging_up_overlay sheet instead of leftover textures.
11. Rhythm track UI reads BPM from RhythmManager (was hard-coded 80 vs the actual 120).
12. Block: parry reduction is graded by the block judgement (perfect 100% / good 80% /
    bad 60%) and only applies to attacks from the front, per AnchorV1.0 section 9.4;
    blocked hits no longer interrupt. block_start active window widened to 0.5 beats
    (total 0.8 beats = 0.4s at 120 BPM, matching the design sheet).

## 2026-07-03 playtest follow-up fixes (bullets / collision / latency / air lock)

Root causes found during the first playtest and their fixes:

1. **Stuck in the air after W then S.** MotionExecutor converted `move_mult_y` into a
   screen-space body velocity; when landing flipped the presentation state to LAND the
   attack-state cleanup never ran, so the plunge left `velocity.y = -220` on the
   CharacterBody and the body ascended forever (vertical motion belongs to the fake
   height system, the body must stay on the ground plane). MotionExecutor is now
   horizontal-only, MovementMotor zeroes `velocity.y` on landing and decays stray
   horizontal knockback velocity (KNOCKBACK_FRICTION 480) whenever no attack owns it.
2. **Bullets looked wrong.** effect_sheet.png is a 6x2 grid of 32px cells (verified by
   alpha scan); the projectile sliced it as 5x2 (38.4px, non-integer) so every frame was
   cut through the middle. The projectile now uses 6x2, loops the four flight frames at
   16 fps, expires by travel range (default 460px, zhan_bo levels 380/460/540) instead
   of a 0.3s animation timer, and flies at 520px/s instead of 1100 so it is readable.
3. **Collision boxes did not match the drawn bodies.** The new art draws both characters
   with their feet ~40px above the node root (player idle rows 24-88 of 128; boss rows
   16-47 with a -67 sprite offset). All body/hurtbox/hitbox shapes still sat at the old
   feet-at-root heights, i.e. ~35px below the visible bodies. Player shapes moved to
   y=-72, boss shapes to y=-70, projectile lanes to -70 on both sides. Player waves now
   also clear enemy bullets (mask includes enemy_hitbox; enemy_projectiles are freed on
   contact) implementing the design's projectile duel.
4. **Blade wave fired away from the boss.** The player heading defaults to left and only
   directional attacks turn it; zhan_bo now aims at the nearest live member of the
   "bosses" group with heading as fallback.
5. **Latency feel.** anchor_grid halved (0.5 -> 0.25 beats) so on-beat presses reach
   Active with no artificial stretch; the four-slot clear display no longer swallows the
   next input (it flushes and consumes immediately); agile input flushing enabled in
   project.godot; player action displacement now follows the S6 rule (move_mult 1.0 =
   100px over the action) instead of a flat 220px/s lunge.

test_boss_integration projectile assertions were rewritten for the new contract
(6x2 grid, flight loop, range expiry, torso-lane spawn heights, moved hurtboxes).

## 2026-07-03 player animation / FX audit vs player_tagged source pack

Audited all 17 tagged action folders against the runtime setup. Root problem: only the
three AnimationPlayer clips (atk_ground_1/2, rising_slash) had FX tracks; every action
running through the manual sheet-animation path had no FX channel at all, and looping
cast animations were being stomped by idle because attack_time_left used the natural
clip length (0.1s for the 2-frame blade rain loop).

- Manual animation system now supports per-segment fps and a parallel FX timeline
  driving Visual/FxOverlay. All overlay offsets were computed by aligning the author's
  embedded frame-0 idle reference against the idle sheet (method reproduces the two
  hand-calibrated offsets exactly): 01/02/03/05 slash (-147,-191), 04 dash (-98,-128),
  07 rising (-111,-156), 08 prep ring (-64,-305), 11 cast (-115,-172),
  12/13 FX2/FX3 (-107,-198).
- FX wired: atk_ground_3 + combo_finisher slash overlays, dash_slash speed-line overlay
  (frame 1 is the author's intentional blank), atk_air FX2, plunge FX2 + FX3 falling
  hold, blade_wave cast overlay, blade_rain launch ring (prep overlay frames 17-19).
- Charge visuals split per entry: A/D charge plays the MAGIC CAST prep body animation
  (hold last frame) with the sword-ring overlay forming (frames 1-16, hold); S charge
  keeps idle stance with CHARGING UP overlay at the author's 50fps.
- Mode C: ContactFxSpawner script added (was a script-less placeholder node) — spawns
  the per-attack ENEMY CONTACT bursts on the target for melee and the projectile
  contact burst for blade waves. Mode D: ground_smash chains three SHOCKWAVE tiles
  along the ground; jian_yu spawns raindrops plus 2-4 RAIN LANDING TILE pillars scaled
  by charge level. One-shot world FX use scenes/combat/one_shot_fx.gd.
- Blade wave projectiles now use the author's PROJECTILE sheet (5 frames, 33fps loop);
  enemy bullets keep the effect_sheet placeholder.
- Smoothness: attack presentation window extended to the action's beat length (idle no
  longer cuts off casts), same-name animations restart on chain (player and boss), and
  starting any new action clears stale FX overlay state. Idle now plays all 8 frames
  (test updated to [0..7]).

## 2026-07-04 full UI reskin (ui_and_ground asset pack) + harbor stage backdrop

The placeholder rhythm-track art (rod/blue_ball stitching, center.png emblem,
yellow_ball movers) was replaced wholesale by the authored pack in ui_and_ground/,
and the stage gained a three-layer harbor backdrop. Map A (past phase) uses the
purple/gold set, map B (future phase) the red "d" set; the world itself still
renders map B via the existing CanvasModulate color mapping + radial wipe.

- RhythmTrack re-skins entirely from `TRACK_SKINS[time_phase]`
  (rhythm_track.gd): background b/bd (single stretched piece — no more rod
  stitching, the line sits centered in the frame), long axis line/lined, center
  emblem anchor01/anchor01d, movers star/stard, special (time anchor) beats swap
  the mover texture to sanchor/sanchord — still zero extra track elements.
- Hit feedback per the art spec: a judged normal beat flips the emblem to the
  own-phase anchor02 variant and fires the own-phase c01 flash; a held special
  beat flips the emblem to the CROSS-phase anchor02 variant with the own-phase
  c02 flash (A: anchor02d + c02, B: anchor02 + c02d). The emblem reverts to
  idle after 0.45s. A latch keeps the follow-up judgement readout from
  overwriting anchor feedback (held resolutions arrive nested inside the same
  judgement_made dispatch; deadline breaks pass an empty judgement dict and
  don't latch).
- Beat ticks now pulse the flash at 0.35 peak alpha so full brightness reads as
  "you hit something"; test_ui_animation_regression asserts visibility > 0.2.
- Stage backdrop: long.png (sunset sea, Parallax2D scroll 0.12, scaled 1.4378 to
  exactly fill the 982px-tall view) and mid.png (lighthouse/ship/crane cluster,
  scroll 0.4, scaled 0.92, bases tucked 17px below the sea horizon at y≈383)
  render behind the ground scene; both are plain-canvas Parallax2D so the
  CanvasModulate phase tint and the radial wipe cover them too.
- ground.png (stone dock with chain railing + end pillars) replaces the old
  strip at uniform scale 1.7979: the walk surface in the art (texture y 570)
  lands exactly on the gameplay ground plane y=366 and the art spans precisely
  boundary-to-boundary (-21.5..4115.5, pillars at the walls). A dark
  StreetUnderfill polygon backfills below the art so the bottom of the frame
  never shows void, and Camera2D got limit_left/right (-22/4116) so the view
  can no longer slide past the artwork at the arena edges.

## 2026-07-04 (later) disaster recovery + WYSIWYG authored view + panel HUD + per-frame collision matrices

Context: at ~05:11 an incomplete Mac zip (Baidu sync had not finished uploading
scenes/assets — the *.baiduyun.uploading.cfg markers) was extracted over the
tree and the merge wiped scenes/, scripts/, tools/, most of resources/ and
assets/. The repo had zero commits, so nothing was recoverable from git. The
tree was rebuilt from four sources: (1) the three session transcripts (every
file ever read/written, replayed Write+Edit chains, most files verified
byte-exact against the surviving .git/index SHA-1s), (2) the old project
(assets, addon, byte-identical UI scenes, the tagged author packs under
assets/art/characters/tmp/new/), (3) ui_and_ground/ + playbossui/ art packs,
(4) the three newer test files carried by the zip (test_rhythm_ui_layout,
test_boss_integration, test_stage4_player_scene), which numerically encode the
newer authored-view state and were treated as the binding spec. A survivor
backup was kept at ../Rthythm_archor_game_survivor_backup_0542. THIS commit
history now exists precisely so this can never happen again.

WYSIWYG (editor == game), per the newer tests:
- Stage exports use_authored_camera_view (default true): the editor-authored
  Camera2D pose IS the runtime view — position (2229.63, 97.38), zoom 0.82,
  no player follow, no zoom overwrite. false restores the legacy follow rig.
- MainUI moved out of CanvasLayer into the world canvas: Main/UI is a Control
  positioned at the camera world-rect origin (1527.191, -297.742) at scale
  1/0.82, sized 1152x648 — the editor shows UI over world exactly as rendered.
- Backgrounds are plain Node2D containers (names LongParallax/MidParallax kept
  for test paths): long.png sunset at (791.6, -335) x1.25, mid.png regions as
  moored ship (1230, -250) and lighthouse (2650, -303); CanvasModulate is
  authored in stage.tscn so the phase tint previews in the editor.
- Ground sprite crops to region Rect2(0, 90, 2301, 593), offset (-1150.5,
  -480) — walk line stays texture y570 = world y366. Actor grounding is
  authored: Visual position (0, 32) with player.gd visual_ground_offset 32.
- Player Visual scale ±2, boss Visual scale ±4 (flip preserves magnitude);
  all scaled sprites use TEXTURE_FILTER_LINEAR.

Panel HUD (playbossui pack): StatusBars at (20.74, 35.64) wraps playerui.png
(x1.5) with HealthBar/EnergyBar/ChargeBar overlaying the baked wells
(player_red_ui/player_blue_ui fills); BossStatus right edge 1123.2 wraps
boss_ui.png with BossHealthBar (boss_red_ui fill) + DREAD HARBINGER name;
ComboWindow centered at y 278.64; TimePhaseHud and DebugPanel ship hidden.

Per-frame collision/damage matrices (frame_collision_driver.gd, on player and
boss): every physics tick the driver re-derives all three matrices from the
frame actually displayed —
- body: base layer/mask re-asserted, composed with MotionExecutor ghost bits;
- damage-receive: DamageReceiver rect follows the opaque pixel bounds of the
  current frame (per-sheet bounds cached from texture alpha), margins via
  hurt_margin, mirrored automatically through the Visual transform;
- damage-send: DamageEmitter only monitors during ACTIVE-phase frames whose
  native-forward extent reaches HIT_REACH_GATE (0.72) of the sheet's max —
  the hit window is the weapon-extended frames, not the whole active phase;
  the shape is rebuilt per frame from pose reach vs action range.
DamageEmitter gained per-swing dedup (_already_hit_ids) since per-frame
windows can re-trigger area_entered within one swing. New headless test:
tests/test_frame_collision_driver.gd (synthetic 4-frame sheet: pose-following
hurtbox, reach-gated hitbox, mirror flip, matrix re-assertion, swing dedup).

Verification pass (9 static-analysis agents over all 39 tests + cross-refs)
confirmed the rebuild and surfaced fixes that were applied:
- grounding: player CharacterSprite/FxOverlay moved to node position (0, 40)
  (visible feet at world 398, camera-frame ratio 0.88; FX stays glued since
  both sprites shift together and all test-pinned offsets are untouched);
  boss.gd gained the set_sprite_height_position override so the authored
  Visual (0, 32) survives physics ticks — boss visible feet land at 398 too.
- driver: forward reach is now facing-derived (boss art is native RIGHT-
  facing, player native LEFT — the mirror sign of basis_x times heading picks
  the correct native side); a late-ACTIVE fallback window guarantees a plain
  range hit if no frame of a swing passes the reach gate (art timing can no
  longer whiff a beat-anchored swing); frame bounds use per-frame
  get_region().get_used_rect() (C++-side, no first-swing hitch).
- test isolation: chart_runner and TimeAnchorSystem resolve bus/manager/clock
  via reverse root-child scan, and only the real TimeAnchorSystem autoload
  self-drives from the global clock (test instances are inert).
- player.gd no longer contains get_parent() (architecture test contract).
Known pre-existing flake (left as-is, documented): test_player_combo_input
judges through the RhythmManager wall clock headless, so ~20% of beat phase
lands in the miss window and the run can abort; other suites pin judgements.
The `libraries/ =` AnimationPlayer serialization was flagged and verified
VALID (per-library subpath form, matches the editor-saved old project), and
hash-verified load_steps miscounts in old .tres files were intentionally kept
(historical bytes, self-healing on editor save).

## 2026-07-04 final Level 1 and menu UI migration baseline

The playable baseline was restored to the `rthythm_archor_game_player`
reference for camera, HUD canvas, actor/background scale, and authored stage
proportions. Level migration is scoped to Level 1 flow, spawn logic, gate state,
and combat sequencing; it must not resize the player, minions, Boss,
background, HUD, or camera.

- `GameFlowManager` now follows the `Rthythm_archor_game` menu implementation
  byte-for-byte and uses the authored menu textures under `assets/ui/menu`.
  Difficulty options apply immediately on click, the difficulty page exposes
  the reference start/back commands, and no current-value label is drawn over
  the command area.
- Stage runtime returns to the player reference view: `UILayer/UI` remains a
  CanvasLayer-hosted HUD, the camera starts at `(2047, 395)` with zoom
  `(1.25, 1.25)`, and camera follow is retained.
- Root ground anchors for player, the initial minion, and Boss stay at
  `y = 560`; the visible sprite feet line is verified at `y = 520` for all
  three actors. Boss uses `visual_ground_offset = -40` and the first active
  minion uses `visual_ground_offset = -32` so the runtime walk/dash frame lines
  up with the same visible baseline without changing actor scale.

## 2026-07-05 charge release facing, blade rain ground line, projectile hit circles

Three combat-feel fixes reported from play: the S-charge release auto-aimed at
the nearest enemy (waves went right whenever a target stood to the right), the
blade rain landing FX rendered 40px below where the player visibly stands, and
enemy bullets carried a hit circle far larger than the drawn bolt.

- Player `projectile_direction` now returns the current facing only (left
  heading releases left); the nearest-enemy auto-aim helper was removed along
  with the projectile-turn branch in `_play_action_animation` (a release no
  longer flips the player toward a target behind them). Regression:
  `tests/test_zhan_bo_release_facing.gd`.
- World-FX ground anchoring: actor origins sit on `y = 560` but the visible
  feet line is `y = 520` (40px transparent margin under the authored player
  frames; minions/boss match via `visual_ground_offset`). Blade rain raindrops
  and landing tiles now anchor to `Player.VISIBLE_GROUND_LINE_OFFSET = -40` so
  the lowest visible pixel of every landing tile shares the player's visible
  ground line instead of sinking into the pier. `tests/test_blade_rain_alignment.gd`
  asserts against the constant.
- Projectile collision must stay inside the visible art: `VISUAL_PROFILES`
  gained `collision_radius` (bullet 9.0 — the effect_sheet bolt is ~32x18px at
  scale 2; wave keeps 32.0, inside its ~66px smallest frame) and
  `_apply_visual_profile` duplicates the scene's shared `CircleShape2D` before
  resizing so bullet/wave instances never overwrite each other. Layer audit
  found emitter/receiver/projectile team masks already correct (player
  projectile also keeps enemy_hitbox in its mask on purpose — wave clears
  enemy bullets). Melee hitboxes untouched: jian_yu keeps its 140px range,
  which stays narrower than the FX spread at every level.
- Known stale test: `test_stage4_player_scene.gd` expects the old 2x-scaled
  player Visual with a `(0, 32)` editor feet preview; it fails against the
  current 1x `player.tscn` regardless of these changes (verified by reverting).