Drawing rotated text is surprisingly difficult with System.Drawing because you can't rotate text - you can only rotate the canvas, then draw text at a location. Rotating the canvas changes the pixel coordinates of where you wanted your text to go.

Rather than using trig to figure out where rotated text should go, I translated the canvas so the text position would be (0, 0), then rotated the canvas an arbitrary amount, then drew the text at (0, 0), then reset everything. It's a bit of a hack but it seems to work.

I'll release this on NuGet this weekend! Thanks for the suggestion.

int pointCount = 50;
double[] dataXs = ScottPlot.DataGen.Consecutive(pointCount);
double[] dataSin = ScottPlot.DataGen.Sin(pointCount);
double[] dataCos = ScottPlot.DataGen.Cos(pointCount);

var plt = new ScottPlot.Plot(width, height);
plt.PlotScatter(dataXs, dataSin);
plt.PlotScatter(dataXs, dataCos);

plt.PlotPoint(25, 0.8, color: Color.Green);
plt.PlotText(" important point", 25, 0.8, 
	color: Color.Green);

plt.PlotPoint(30, 0.3, color: Color.Black, markerSize: 15);
plt.PlotText(" default alignment", 30, 0.3, 
	fontSize: 16, bold: true, color: Color.Magenta);

plt.PlotPoint(30, 0, color: Color.Black, markerSize: 15);
plt.PlotText("middle center", 30, 0, 
	fontSize: 16, bold: true, color: Color.Magenta,
	alignment: ScottPlot.TextAlignment.middleCenter);

plt.PlotPoint(30, -0.3, color: Color.Black, markerSize: 15);
plt.PlotText("upper left", 30, -0.3,
	fontSize: 16, bold: true, color: Color.Magenta,
	alignment: ScottPlot.TextAlignment.upperLeft);

plt.PlotPoint(5, -.5, color: Color.Blue, markerSize: 15);
plt.PlotText(" Rotated Text", 5, -.5, 
	fontSize: 16, color: Color.Blue, bold: true, rotation: -30);

plt.SaveFig("demo.png");

PlotText() custom rotation #160

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