Hi Petar, thanks for the reply.
I don't think we've resolved the orignial issue, as it is still an issue for BarSeries even without point templates (see below). Now that we understand it better, it's more an issue with logarithmic axes than any particular type of series, so if you're able to edit the subject please go ahead and rename it to something more appropriate for future searchers.
For my part, I think your explanation is sufficient to close the need for any further discussion. I will open a support ticket instead, since there doen't seem to be a reasonable work-around. Simply not adding 0 data points would be like saying you have to remove data points that are below your "Minimum" value on any of your axes; not reasonable for something working with real data, and certainly not something you'd expect to have to do with toolkit controls. Not drawing points/bars/lines that fall below the minimum value of your axis isn't "simply closing its eyes", it's doing what the control was asked to do by the establishment of a minimum on that axis.
A more reasonable handling of points that fall off the bottom of a log axis would be to "plot" them at double.Epsilon (the smallest positive number), which yields the expected chart (see epsilon.png) for lineseries and pointseries (not actually plotting them at all). This was achieved by substituting the following in my above example for the point generation:
PointSeries.DataPoints.Add(
new
Telerik.Charting.CategoricalDataPoint()
{Category = DateTime.Today.AddDays(i),
Value = i%2 == 0 ?
double
.Epsilon : i/5.0});
LineSeries.DataPoints.Add(
new
Telerik.Charting.CategoricalDataPoint()
{ Category = DateTime.Today.AddDays(i),
Value = Math.Max(
double
.Epsilon,4.0-i/2.0) });
Again, not something that should be necessary in production code.
Interestingly, doing this shows that what's actually happening with BarSeries is that the bars are being drawn from 1 to the desired value, whether that is going up or down. This means any BarSeries on a Log axis with values < 1 will be incorrect. See barseries.png.
Thanks again,
Louis