I was wondering if there is a way to draw a rectangle in a scrolling graph. What I want to do is start drawing a rectangle when the user presses the spacebar and stop drawiing the rectangle when the user releases the spacebar. I want the rectangle to be filled in with a semitransparent color. I want the rectangle to cover the whole area of the graphing y-axis but only the specified area of the x-axis. This area also needs to scroll with the graph as it moves. Is this even possible?
Yes, it would be possible, though we could not explain how to do it unelss we wrote a complete example to work out the details. That is what our Services group is for, see http://quinn-curtis.com/Services.htm . If you wish to get a quote on what it would take to write such an example you should contact sales@quinn-curtis.com.