public Matrix GetAbsoluteTransformAtTime(float time)
{
Matrix parentTransform = Matrix.Identity;
if (Parent != null)
{
parentTransform = Parent.GetAbsoluteTransformAtTime(time);
}
Matrix transform = Transform;
if (Keyframes.Any())
{
var framesBefore = Keyframes.Where(x => x.Time < time);
var framesAfter = Keyframes.Where(x => x.Time > time);
var frame1 = framesBefore.Any() ? framesBefore.Last() : Keyframes.First();
var frame2 = framesAfter.Any() ? framesAfter.First() : Keyframes.Last();
transform = Matrix.Lerp(frame1.Transform, frame2.Transform, Math.Min((time - frame1.Time) / (float)(frame2.Time - frame1.Time), 1f)) * Transform;
}
return(transform * parentTransform);
}