Adapt game input for Switch controllers

game/docs/planning/game_architecture_board.md

@@ -123,11 +123,18 @@ mindmap
 - `core/asset_paths.h`
 - `core/input_state.*`
 - `core/debug_flags.h`
+- `InputStateProvider` 已聚合键盘、SDL GameController 和 Switch 原生 `PadState`。
+
+当前输入映射：
+
+- 移动：键盘 `A/D`、方向键、手柄左摇杆、方向键、Switch 左摇杆/方向键。
+- 跳跃：键盘 `Space/W/Up`、手柄 `A/B`、Switch `A/B`。
+- 攻击：键盘 `J/K`、手柄 `X/Y`、Switch `X/Y`。
 
 下一步：
 
 - 增加 `GameContext`，统一传递全局服务。
-- 输入层支持键盘和手柄统一映射。
+- 增加可配置键位表，让 PC 和 NS 可以分别覆盖默认映射。
 
 ### 2. Scene
 
@@ -312,7 +319,6 @@ mindmap
 
 下一步：
 
-- 将 Switch Joy-Con 输入接入 `InputStateProvider`。
 - 在 Ryujinx 或真机上验证主循环、shader 和角色纹理。
 - 如果 RomFS 不可用，再补 SD 卡外部资源部署脚本。
 
@@ -320,7 +326,7 @@ mindmap
 
 ```text
 输入
-  SDL Keyboard / Controller
+  SDL Keyboard / Controller / Switch PadState
     -> InputStateProvider
       -> InputState
         -> PlayerActor
@@ -401,11 +407,11 @@ mindmap
 下一步建议按这个顺序做：
 
 1. `BattleZone`：做清版推进的核心框架。
-2. `SwitchInput`：把 Joy-Con/手柄输入接入 `InputStateProvider`。
-3. `EnemyActor`：做第一个敌人占位。
-4. `CombatSystem`：把 hitbox/hurtbox 真正跑起来。
-5. `SpriteAnimator`：把玩家动画从硬编码改成组件。
-6. `StageLayer`：把白盒视觉层扩展为背景、tiles 和 props。
+2. `EnemyActor`：做第一个敌人占位。
+3. `CombatSystem`：把 hitbox/hurtbox 真正跑起来。
+4. `SpriteAnimator`：把玩家动画从硬编码改成组件。
+5. `StageLayer`：把白盒视觉层扩展为背景、tiles 和 props。
+6. `InputConfig`：把默认键位/手柄映射迁移到可配置数据。
 
 ## 素材协作提示
 

game/src/core/input_state.cpp

@@ -1,34 +1,141 @@
 #include "input_state.h"
 
 #include <SDL2/SDL.h>
+#include <algorithm>
+
+#ifdef __SWITCH__
+#include <switch.h>
+#endif
 
 namespace ns_game {
 
 namespace {
 
+constexpr Sint16 kControllerAxisDeadZone = 10000;
+
 bool isDown(const Uint8* keys, SDL_Scancode key) {
   return keys && keys[key] != 0;
 }
 
+bool controllerButtonDown(SDL_GameController* controller,
+                          SDL_GameControllerButton button) {
+  return controller &&
+         SDL_GameControllerGetButton(controller, button) == SDL_PRESSED;
+}
+
+Sint16 controllerAxis(SDL_GameController* controller,
+                      SDL_GameControllerAxis axis) {
+  if (!controller) {
+    return 0;
+  }
+  return SDL_GameControllerGetAxis(controller, axis);
+}
+
+#ifdef __SWITCH__
+PadState& switchPad() {
+  static PadState pad;
+  static bool initialized = false;
+  if (!initialized) {
+    padInitializeDefault(&pad);
+    initialized = true;
+  }
+  return pad;
+}
+#endif
+
 } // namespace
 
+InputStateProvider::InputStateProvider() {
+  ensureController();
+}
+
+InputStateProvider::~InputStateProvider() {
+  if (controller_) {
+    SDL_GameControllerClose(controller_);
+    controller_ = nullptr;
+  }
+}
+
+void InputStateProvider::ensureController() {
+  if (controller_) {
+    return;
+  }
+
+  const int joystickCount = SDL_NumJoysticks();
+  for (int i = 0; i < joystickCount; ++i) {
+    if (!SDL_IsGameController(i)) {
+      continue;
+    }
+
+    controller_ = SDL_GameControllerOpen(i);
+    if (controller_) {
+      SDL_Log("InputStateProvider opened controller: %s",
+              SDL_GameControllerName(controller_));
+      return;
+    }
+  }
+}
+
 InputState InputStateProvider::Sample() {
+  ensureController();
+
   const Uint8* keys = SDL_GetKeyboardState(nullptr);
   InputState state;
+  bool moveLeftHeld = false;
+  bool moveRightHeld = false;
 
   if (isDown(keys, SDL_SCANCODE_A) || isDown(keys, SDL_SCANCODE_LEFT)) {
-    state.moveX -= 1.0f;
+    moveLeftHeld = true;
   }
   if (isDown(keys, SDL_SCANCODE_D) || isDown(keys, SDL_SCANCODE_RIGHT)) {
-    state.moveX += 1.0f;
+    moveRightHeld = true;
   }
 
-  const bool jumpHeld =
+  bool jumpHeld =
       isDown(keys, SDL_SCANCODE_SPACE) || isDown(keys, SDL_SCANCODE_W) ||
       isDown(keys, SDL_SCANCODE_UP);
-  const bool attackHeld =
+  bool attackHeld =
       isDown(keys, SDL_SCANCODE_J) || isDown(keys, SDL_SCANCODE_K);
 
+  if (controller_) {
+    const Sint16 leftX =
+        controllerAxis(controller_, SDL_CONTROLLER_AXIS_LEFTX);
+    moveLeftHeld = moveLeftHeld ||
+                   leftX < -kControllerAxisDeadZone ||
+                   controllerButtonDown(controller_,
+                                        SDL_CONTROLLER_BUTTON_DPAD_LEFT);
+    moveRightHeld = moveRightHeld ||
+                    leftX > kControllerAxisDeadZone ||
+                    controllerButtonDown(controller_,
+                                         SDL_CONTROLLER_BUTTON_DPAD_RIGHT);
+    jumpHeld = jumpHeld ||
+               controllerButtonDown(controller_, SDL_CONTROLLER_BUTTON_A) ||
+               controllerButtonDown(controller_, SDL_CONTROLLER_BUTTON_B);
+    attackHeld = attackHeld ||
+                 controllerButtonDown(controller_, SDL_CONTROLLER_BUTTON_X) ||
+                 controllerButtonDown(controller_, SDL_CONTROLLER_BUTTON_Y);
+  }
+
+#ifdef __SWITCH__
+  PadState& pad = switchPad();
+  padUpdate(&pad);
+  const u64 buttons = padGetButtons(&pad);
+  moveLeftHeld = moveLeftHeld || (buttons & HidNpadButton_AnyLeft) != 0;
+  moveRightHeld = moveRightHeld || (buttons & HidNpadButton_AnyRight) != 0;
+  jumpHeld = jumpHeld ||
+             (buttons & (HidNpadButton_A | HidNpadButton_B)) != 0;
+  attackHeld = attackHeld ||
+               (buttons & (HidNpadButton_X | HidNpadButton_Y)) != 0;
+#endif
+
+  if (moveLeftHeld) {
+    state.moveX -= 1.0f;
+  }
+  if (moveRightHeld) {
+    state.moveX += 1.0f;
+  }
+  state.moveX = std::clamp(state.moveX, -1.0f, 1.0f);
+
   state.jumpPressed = jumpHeld && !jumpHeldLastFrame_;
   state.attackPressed = attackHeld && !attackHeldLastFrame_;
 

game/src/core/input_state.h

@@ -1,5 +1,7 @@
 #pragma once
 
+#include <SDL2/SDL_gamecontroller.h>
+
 namespace ns_game {
 
 struct InputState {
@@ -10,9 +12,18 @@ struct InputState {
 
 class InputStateProvider {
 public:
+  InputStateProvider();
+  ~InputStateProvider();
+
+  InputStateProvider(const InputStateProvider&) = delete;
+  InputStateProvider& operator=(const InputStateProvider&) = delete;
+
   InputState Sample();
 
 private:
+  void ensureController();
+
+  SDL_GameController* controller_ = nullptr;
   bool jumpHeldLastFrame_ = false;
   bool attackHeldLastFrame_ = false;
 };