游戏中的曲线艺术

public static class Easing {
    // 1. Sine (正弦) - 柔和
    public static float EaseInSine(float t) => 1 - Mathf.Cos((t * Mathf.PI) / 2);
    public static float EaseOutSine(float t) => Mathf.Sin((t * Mathf.PI) / 2);

    // 2. Power Curves (Quad, Cubic, Quart, Quint) - 力度递增
    public static float EaseInQuad(float t) => t * t;
    public static float EaseOutQuad(float t) => 1 - (1 - t) * (1 - t);

    public static float EaseInCubic(float t) => t * t * t;
    public static float EaseOutCubic(float t) => 1 - Mathf.Pow(1 - t, 3);

    public static float EaseInQuart(float t) => t * t * t * t;
    public static float EaseOutQuart(float t) => 1 - Mathf.Pow(1 - t, 4);

    public static float EaseInQuint(float t) => t * t * t * t * t;
    public static float EaseOutQuint(float t) => 1 - Mathf.Pow(1 - t, 5);

    // 3. Expo (指数) - 爆发
    public static float EaseInExpo(float t) => t == 0 ? 0 : Mathf.Pow(2, 10 * t - 10);
    public static float EaseOutExpo(float t) => t == 1 ? 1 : 1 - Mathf.Pow(2, -10 * t);

    // 4. Circ (圆形) - 突然
    public static float EaseInCirc(float t) => 1 - Mathf.Sqrt(1 - Mathf.Pow(t, 2));
    public static float EaseOutCirc(float t) => Mathf.Sqrt(1 - Mathf.Pow(t - 1, 2));

    // 5. Back (回弹) - 预备/过冲
    public static float EaseInBack(float t) {
        float c1 = 1.70158f; float c3 = c1 + 1;
        return c3 * t * t * t - c1 * t * t;
    }
    public static float EaseOutBack(float t) {
        float c1 = 1.70158f; float c3 = c1 + 1;
        return 1 + c3 * Mathf.Pow(t - 1, 3) + c1 * Mathf.Pow(t - 1, 2);
    }

    // 6. Elastic (弹簧) - 弹性
    public static float EaseOutElastic(float t) {
        float c4 = (2 * Mathf.PI) / 3;
        return t == 0 ? 0 : t == 1 ? 1 : Mathf.Pow(2, -10 * t) * Mathf.Sin((t * 10 - 0.75f) * c4) + 1;
    }

    // 7. Bounce (弹跳) - 撞击
    public static float EaseOutBounce(float t) {
        float n1 = 7.5625f; float d1 = 2.75f;
        if (t < 1 / d1) return n1 * t * t;
        else if (t < 2 / d1) return n1 * (t -= 1.5f / d1) * t + 0.75f;
        else if (t < 2.5f / d1) return n1 * (t -= 2.25f / d1) * t + 0.9375f;
        else return n1 * (t -= 2.625f / d1) * t + 0.984375f;
    }
}

// 二阶贝塞尔
public static Vector3 GetPoint(Vector3 p0, Vector3 p1, Vector3 p2, float t) {
    t = Mathf.Clamp01(t);
    float oneMinusT = 1f - t;
    return oneMinusT * oneMinusT * p0 +
           2f * oneMinusT * t * p1 +
           t * t * p2;
}

float Remap(float value, float from1, float to1, float from2, float to2) {
    return (value - from1) / (to1 - from1) * (to2 - from2) + from2;
}