移动与冲刺系统 (Movement & Dash System)

Velocity(t) = DashSpeed * (1 - (t / DashDuration)^Power)

其中:
- DashSpeed: 初始爆发速度
- DashDuration: 冲刺总时长
- Power: 衰减指数 (通常 > 1，如 2 或 3，使速度快速下降)

[System.Serializable]
public class MovementConfig
{
    [Header("基础移动")]
    public float moveSpeed = 8.0f;
    public float acceleration = 50.0f; // 起步加速度
    public float deceleration = 60.0f; // 停止摩擦力
    
    [Header("冲刺参数")]
    public float dashDistance = 6.0f;
    public float dashDuration = 0.3f;
    public AnimationCurve dashSpeedCurve; // 速度变化曲线
    
    [Header("冷却与资源")]
    public int maxDashCharges = 2;
    public float dashCooldown = 1.2f; // 充能恢复时间
    public float dashInternalCooldown = 0.15f; // 连续冲刺最小间隔
    
    [Header("高级机制")]
    public float iframeDuration = 0.2f; // 无敌时间
    public bool canDashThroughEnemies = true;
    public LayerMask obstacleLayer; // 阻挡层（墙壁、塔基）
}

public class PlayerMovement : MonoBehaviour
{
    public MovementConfig config;
    private CharacterController cc;
    private Vector3 velocity;
    private float currentDashTime;
    private Vector3 dashDirection;
    
    private enum State { Normal, Dashing, Stunned }
    private State currentState;
    
    void Update()
    {
        switch (currentState)
        {
            case State.Normal:
                HandleNormalMovement();
                HandleDashInput();
                break;
            case State.Dashing:
                HandleDashMovement();
                break;
        }
    }
    
    void HandleNormalMovement()
    {
        Vector3 input = GetInputVector();
        
        // 简单的加减速处理
        if (input.magnitude > 0.1f)
        {
            // 加速向目标速度
            Vector3 targetVel = input * config.moveSpeed;
            velocity = Vector3.MoveTowards(velocity, targetVel, config.acceleration * Time.deltaTime);
        }
        else
        {
            // 减速至静止
            velocity = Vector3.MoveTowards(velocity, Vector3.zero, config.deceleration * Time.deltaTime);
        }
        
        cc.Move(velocity * Time.deltaTime);
        
        // 朝向移动方向
        if (velocity.sqrMagnitude > 0.1f)
            transform.forward = velocity.normalized;
    }
    
    void StartDash()
    {
        if (dashCharges <= 0) return;
        
        dashCharges--;
        currentState = State.Dashing;
        currentDashTime = 0f;
        
        // 确定冲刺方向：如果有输入则按输入方向，否则按角色朝向
        Vector3 input = GetInputVector();
        dashDirection = input.magnitude > 0.1f ? input.normalized : transform.forward;
        
        // 开启无敌
        StartCoroutine(IFrameRoutine());
        
        // 播放特效和音效
        PlayDashEffects();
    }
    
    void HandleDashMovement()
    {
        currentDashTime += Time.deltaTime;
        float progress = currentDashTime / config.dashDuration;
        
        if (progress >= 1f)
        {
            EndDash();
            return;
        }
        
        // 采样速度曲线
        float speedMultiplier = config.dashSpeedCurve.Evaluate(progress);
        float currentSpeed = (config.dashDistance / config.dashDuration) * speedMultiplier;
        
        cc.Move(dashDirection * currentSpeed * Time.deltaTime);
    }
}

IEnumerator IFrameRoutine()
{
    // 1. 开启无敌状态（免疫伤害逻辑在 Health 组件中检查此标志）
    isInvincible = true;
    
    // 2. 忽略与敌人的物理碰撞（防止被卡住）
    Physics.IgnoreLayerCollision(LayerMask.NameToLayer("Player"), LayerMask.NameToLayer("Enemy"), true);
    
    yield return new WaitForSeconds(config.iframeDuration);
    
    // 3. 恢复碰撞
    Physics.IgnoreLayerCollision(LayerMask.NameToLayer("Player"), LayerMask.NameToLayer("Enemy"), false);
    isInvincible = false;
}

// 简单的转角修正逻辑示意
void HandleCornerSliding(Vector3 moveDir)
{
    if (Physics.Raycast(transform.position, moveDir, out RaycastHit hit, 1f, obstacleLayer))
    {
        // 如果撞墙角度很小（擦边），则修正移动方向沿墙面滑动
        Vector3 slideDir = Vector3.ProjectOnPlane(moveDir, hit.normal).normalized;
        cc.Move(slideDir * speed * Time.deltaTime);
    }
}