This topic provides examples that demonstrate how to draw a single pixel and how to draw a point with a pen three-pixels wide.
Use Plot() to draw a single point in the center of the screen. 
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TPoint screenCenterPoint=rect.Center(); // the center of the screen
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// draw a single pixel point in the center of the screen
gc.Plot(screenCenterPoint);
... Define a size for the pen tip as a TSize. 
Use SetPenSize() to increase the pen width from the default (single pixel). This shows how a plotted point three pixels wide is much easier to see than a single pixel. It is in fact drawn as a "+" shape. 
Use Plot() to draw a point in the center of the screen. 
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TPoint screenCenterPoint=rect.Center(); // the center of the screen
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// Set up a "bold" size for the pen tip to (default is 1,1)
TSize penSizeBold(3,3);
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// draw a "bold" point 3 pixels across
gc.SetPenSize(penSizeBold);
gc.Plot(screenCenterPoint);
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