When you zoom in so that the graph does not contain any points, nothing is drawn. However if you zoom in to one point the lines are drawn to the points outside the GDI's clipping region. In the LinePlot.cs file I found the following code:
// do horizontal clipping here, to speed up
if ((dx1 < leftCutoff || rightCutoff < dx1) &&
(dx2 < leftCutoff || rightCutoff < dx2))
{
continue;
}
This code does not draw any lines if one point is on the left and the other is on the right. In this case you would want the line to be drawn. Here is an update to that clipping code that takes into account that scenario:
if (dx1 < leftCutoff && dx2 < leftCutoff)
{
// Both points are to the left of the clipping region.
continue;
}
else if (dx1 > rightCutoff && dx2 > rightCutoff)
{
// Both points are to the right of the clipping region.
continue;
}
If you have further questions, please feel free to contact me.
Bob Cravens (bob.cravens@gmail.com)