public override float GetFrameValue(float frame, float startFrame = 0)
{
if (InterpolationType == STInterpoaltionType.Constant)
{
return(Constant);
}
if (KeyFrames.Count == 0)
{
return(0);
}
if (KeyFrames.Count == 1)
{
return(KeyFrames[0].Value);
}
STKeyFrame LK = KeyFrames.First();
STKeyFrame RK = KeyFrames.Last();
float Frame = frame - startFrame;
foreach (STKeyFrame keyFrame in KeyFrames)
{
if (keyFrame.Frame <= Frame)
{
LK = keyFrame;
}
if (keyFrame.Frame >= Frame && keyFrame.Frame < RK.Frame)
{
RK = keyFrame;
}
}
if (LK.Frame != RK.Frame)
{
float FrameDiff = Frame - LK.Frame;
float Weight = FrameDiff / (RK.Frame - LK.Frame);
switch (InterpolationType)
{
case STInterpoaltionType.Constant: return(LK.Value);
case STInterpoaltionType.Step: return(LK.Value);
case STInterpoaltionType.Linear: return(InterpolationHelper.Lerp(LK.Value, RK.Value, Weight));
case STInterpoaltionType.Bezier:
{
return(InterpolationHelper.Lerp(LK.Value, RK.Value, Weight));
STBezierKeyFrame bezierKeyLK = (STBezierKeyFrame)LK;
STBezierKeyFrame bezierKeyRK = (STBezierKeyFrame)RK;
float length = RK.Frame - LK.Frame;
return(InterpolationHelper.BezierInterpolate(frame,
bezierKeyLK.Frame,
bezierKeyRK.Frame,
bezierKeyLK.SlopeIn,
bezierKeyRK.SlopeOut,
bezierKeyLK.Value,
bezierKeyRK.Value));
}
case STInterpoaltionType.Hermite:
{
STHermiteKeyFrame hermiteKeyLK = (STHermiteKeyFrame)LK;
STHermiteKeyFrame hermiteKeyRK = (STHermiteKeyFrame)RK;
float length = RK.Frame - LK.Frame;
return(InterpolationHelper.HermiteInterpolate(frame,
hermiteKeyLK.Frame,
hermiteKeyRK.Frame,
hermiteKeyLK.TangentIn,
hermiteKeyLK.TangentOut,
hermiteKeyLK.Value,
hermiteKeyRK.Value));
}
}
}
return(LK.Value);
}