缓动函数

缓动函数指定动画效果在执行时的速度，使其看起来更加真实。

现实物体照着一定节奏移动，并不是一开始就移动很快的。当我们打开抽屉时，首先会让它加速，然后慢下来。当某个东西往下掉时，首先是越掉越快，撞到地上后回弹，最终才又碰触地板。

• 缓动函数概览参考博客:

• EaseIn、EaseOut、EaseInOut:对于一个缓动函数，EaseIn是在开始是缓冲，即开始时变化较慢，EaseOut是在结束是缓冲，即结束时变化较慢，而EaseInOut是两者兼有。
• 更多缓动函数细节可参照msdn介绍
• 缓动函数图示可参照Easings缓动函数速查表

SetEase方法

SetEase(Ease easeType \ AnimationCurve animCurve \ EaseFunction customEase)

设置动画的缓动。

如果应用于一个序列而不是Tweener，这个ease将被应用到整个序列，就好像它是一个单一的动画时间轴。序列总是有缓动。默认情况下是线性的，独立于全局默认设置.

You can pass it either a default ease (Ease – to see how default ease curves look, check out easings.net), an AnimationCurve or a custom ease function (see example).

此外，还可以设置以下可选参数:它们只在Back和Elastic的eases中工作。

• overshoot Eventual overshoot to use with Back ease (default is 1.70158), or number of flashes to use with Flash ease.
• amplitude Eventual amplitude to use with Elastic ease (default is 1.70158).

• period Eventual period to use with Elastic ease (default is 0), or power to use with Flash ease.

  特例

  Flash, InFlash, OutFlash,InOutFlash:这些缓动会对动画应用一个闪烁效果，下面的图片很清楚地表明了这点

• overshoot: Indicates the total number of flashes to apply. An even number will end the tween on the starting value, while an odd one will end it on the end value.

• period: Indicates the power in time of the ease, and must be between -1 and 1.
  0 is balanced, 1 fully weakens the ease in time, -1 starts the ease fully weakened and gives it power towards the end.

EXTRA: EaseFactory

EaseFactory.StopMotion 是一个额外的Layer，你可以添加到你的easings，使他们的行为就好像他们是在停止运动

EaseFactory.StopMotion(int fps, Ease\AnimationCurve\EaseFunction ease)

transform.DOMoveX(4, 1).SetEase(EaseFactory.StopMotion(5, Ease.InOutQuint));

DOTWeen缓动枚举

public enum Ease{Unset = 0,Linear = 1,InSine = 2,OutSine = 3,InOutSine = 4,InQuad = 5,OutQuad = 6,InOutQuad = 7,InCubic = 8,OutCubic = 9,InOutCubic = 10,InQuart = 11,OutQuart = 12,InOutQuart = 13,InQuint = 14,OutQuint = 15,InOutQuint = 16,InExpo = 17,OutExpo = 18,InOutExpo = 19,InCirc = 20,OutCirc = 21,InOutCirc = 22,InElastic = 23,OutElastic = 24,InOutElastic = 25,InBack = 26,OutBack = 27,InOutBack = 28,InBounce = 29,OutBounce = 30,InOutBounce = 31,Flash = 32,InFlash = 33,OutFlash = 34,InOutFlash = 35,//// 摘要://     Don't assign this! It's assigned automatically when creating 0 duration tweensINTERNAL_Zero = 36,//// 摘要://     Don't assign this! It's assigned automatically when setting the ease to an AnimationCurve//     or to a custom ease functionINTERNAL_Custom = 37}