Just a quick follow up to this. You can create a smooth-drag effect by changing the values on the axes rather than modifying the dataset for the chart - this will give a pixel-by-pixel drag effect. See Ely Greenfield's Interactive Bubble Chart at [1] for an example.
There are a few downsides though: 1) Edges are only drawn between points within the chart, so you always have a gap between the last point and the edge of the chart. 2) There's a problem with the default AxisRenderer that this technique exposes. I've made another post about that at [2]. The example in that post uses a BubbleChart, but all the principals apply to LineCharts too. Matt. [1] http://www.quietlyscheming.com/blog/charts/interactive-bubble-chart/ [2] http://tech.groups.yahoo.com/group/flexcoders/message/118194
