Hi @StendProg, thanks for this fix!

I identified a rendering issue that caused downward sloping lines to appear too thick. I figured out it was because LineTo() was drawing extra pixels as it jumped from the top of one vertical bar to the bottom of the next. I think I fixed it in a reasonable way, but I always welcome your input!

I'll merge this in now and we can create a new PR to improve or refine this code if needed 👍

Before

After

Hi @swharden,

Yes, it does look better with your extra fix. But we can find a counterexample for it too. For example, when neighboring pixel columns do not overlap by Y, then they will be unconnected.

If we continue these improvements, we can do what SignalXY draws for a single column:

1. Line (Column[i-1].Right, Column[i].Left)
2. Line (Column[i].Top, Column[i].Bottom)
3. Line (Column[i].Right, Column[i+1].Left)
   

The blue color indicates the original signal.
Rectangles mark the pixel column.
Green color indicates the lines to be drawn.

Thanks for the feedback @StendProg!

when neighboring pixel columns do not overlap by Y, then they will be unconnected

I'm having trouble demonstrating this with code... do you have a similar code example I can use to check that the issue is present and confirm when it has been fixed?

Here's my attempt so far:

[Test]
public void Test_Signal_VerticalGap()
{
    double[] data = Generate.Sin(10_000, oscillations: 100);
    for (int i = (int)(data.Length * .3); i < (int)(data.Length * .7); i++)
    {
        data[i] = data[i] + 10;
    }

    ScottPlot.Plot plt = new();
    var sig = plt.Add.Signal(data);
    sig.LineStyle.AntiAlias = false;
    plt.Grids.Clear();
    plt.SaveTestImage();
}

In theory the artifact you describe with the green squares makes sense, but in practice it's pretty hard to demonstrate

using ScottPlot;
using ScottPlot.WinForms;

double[] data = Generate.Sin(10_000, oscillations: 100);
for (int i = (int)(data.Length * .3); i < (int)(data.Length * .7); i++)
    data[i] = data[i] + 10;

Plot plot = new();
plot.Add.Signal(data);

Form form = new()
{
    Width = 600,
    Height = 400,
    StartPosition = FormStartPosition.CenterScreen
};

FormsPlot formsPlot1 = new()
{
    Dock = DockStyle.Fill
};

formsPlot1.Reset(plot);
formsPlot1.Refresh();
form.Controls.Add(formsPlot1);
form.ShowDialog();

If we continue these improvements, we can do what SignalXY draws for a single column:

This is probably the best solution, and it would be nice to share code between Signal and SignalXY

I'll work on that in a new issue/PR #2949

I was able to get this on the latest version:

I think the code will need a lot of reworking, but you're right that it should be a separate task.

You failed to reproduce the effect I described earlier because the X ranges for the pixel columns overlap (which should not be the case) and the data points can be included in both columns.
The overlap is most likely due to rounding in these rows: