private void PutDown(TreapNode child) { if (child == null) { return; } child.yOffset += this.yOffsetTag; child.yOffsetTag += this.yOffsetTag; //this.yOffsetTag = 0; if (animationStartTimeTag != DateTime.MinValue) { child.AppendAnimation(animationStartTimeTag, animationOffsetTag); //animationStartTimeTag = DateTime.MinValue; } }