/// <summary>Tweens a 2D Toolkit Sprite's color using the given gradient
/// (NOTE 1: only uses the colors of the gradient, not the alphas - NOTE 2: creates a Sequence, not a Tweener).
/// Also stores the image as the tween's target so it can be used for filtered operations</summary>
/// <param name="gradient">The gradient to use</param><param name="duration">The duration of the tween</param>
public static Sequence DOGradientColor(this tk2dBaseSprite target, Gradient gradient, float duration)
{
Sequence s = DOTween.Sequence();
GradientColorKey[] colors = gradient.colorKeys;
int len = colors.Length;
for (int i = 0; i < len; ++i)
{
GradientColorKey c = colors[i];
if (i == 0 && c.time <= 0)
{
target.color = c.color;
continue;
}
float colorDuration = i == len - 1
? duration - s.Duration(false) // Verifies that total duration is correct
: duration * (i == 0 ? c.time : c.time - colors[i - 1].time);
s.Append(target.DOColor(c.color, colorDuration).SetEase(Ease.Linear));
}
return(s);
}