Bug Report

Issue: an "OutOfMemoryException" is fired whenever the SweepAngle property in any of the gauges's is equal or below 0.01.

Explanation: according to this post it seems that DrawArc doesn't handle very well the combination of pen width and small sweep angles.

Reproducing: using these values, the DrawArc function fails for sweep angles equal of below 0.01. However, using less values (less gauges, which result in a wider pen width does modify the 0.01 threshold limit.

var plt = new ScottPlot.Plot(600, 400);
double[] values = { 505, 590, 0.005, 0.005, 0.0005, 0.005, 0.005, 0.0005 };
plt.AddRadialGauge(values);

Solution: either check for values lower than 0.01 when creating the plot's RadialGauge instances

SweepAngle = sweepAngles[index] <= 0.01 ? 0 :  sweepAngles[index],

or make the checking when calling DrawArc inside the RenderGaugeForeground function (it might be wiser to do the same inside RenderBackground):

gfx.DrawArc(
                pen,
                (center.X - radius),
                (center.Y - radius),
                (radius * 2),
                (radius * 2),
                (float)StartAngle,
                SweepAngle <= 0.01 ? 0 : (float)SweepAngle);

These suggestions are GDI+ dependant, meaning that they might not be needed whenever ScottPlot is ported to other graphics library.

System Details

• ScottPlot Version: 4.1.27
• Operating System: Windows 11
• Application Type: WinForms
• .NET Version: .NET 6.0