I'm not at all familiar with advanced charting packages and hope I do not use the wrong terminology.

Is it possible, using EasyLanguage, to define your own draw tool in TradeStation?

I.e the user, via mouse clicks, chooses points 1,2,3 (high, low, retrace) and the charting software draws three diagonal trend lines and automatically adds a couple of horizontal lines on the retrace trendline based on a fib. type relationship.

If TradeStation can't, are there any charting packages that allow you to define your own tool like this?