Thank you Yeray. It was helpful.
(BTW I discovered that TFastLine can handle NULL points, I just overlooked properties IgnoreNulls and TreatNulls)

(TeeChart for C++ Builder 2009 ) I need to draw large moving line graph which have "holes" (isn't continuous). Currently I'm using TLineSeries and functions AddXY and AddNullXY but it's too slow. TFastLineSeries is faster but it can't draw "holes" - AddNullXY just add point with value 0. I tried to ...