RRDTool graph plotting method

Folks,

let me know if anyone has done this. I am able to generate graphs using RRDTool and nagiostat. Here is my qyestion, Suppose there are two data points A and B. To actually plot a line between A and B, RRDTool first draws a horizontal line from data point A to B and then draws a vertical line to B. Is there any way I can draw a direct straight line between A and B ? I am not sure I am asking my question in right way, but I am sure whoever has done it before will understand this. Can we actually change the way a line is drawn between two data points ?

Help me guys!
Thanks

ok…so seems there is nothing much I can do about plotting the graph. Stair-case curves are the default way of graph plotting. The other way is slope method but even that doesn’t make much of a diffrence.