Awesome code you've sent, thank you! it gave me some ideas to another problem that I'll be facing in the future
I've thought of that, but wanted to see if there was something that I was missing.
I was studying TAChart code and seems to me that makes more sense to update the tachart package, at least for the TLineSeries the TAreaSeries is a little more complex, will take a litte more time.
I've made TLineSeries work like a charm with minimal changes (wouldn't break any compatibility).
Now I'll try to figure out how can I send a suggestion of improvement to the official Dev team, maybe they can include this to the official release so more people can benefit from this functionality.
If you know how to do this kind of suggestion, I'd appreciate also.