Draw a single pixel dot

Once again GDI+ resolution independence jumps up to bite you in the soft and tender parts. There is no PlotPixel function in GDI+ that allows you to draw directly on the GDI Graphics surface as we used to be able to in GDI..

To draw a dot of a specific colour on your screen you must resort to the following shenanigans.

Create a 1x1 bitmap image
Set its only pixel to the colour you desire using Bitmap.SetPixel
use Graphics.DrawImageUnscaled(...) to draw the dot in the correct place

The following example assume that they are in a Paint event handler.

[C#]

Bitmap bm=new Bitmap(1,1);

bm.SetPixel(0,0,Color.Red);

e.Graphics.DrawImageUnscaled(bm,<xPosition>,<yPosition>);

[VB]

Dim bm as new Bitmap(1,1)

bm.SetPixel(0,0,Color.Red)

e.Graphics.DrawImageUnscaled(bm,<xPosition>,<yPosition>)

Remember that you don't have to create the bitmap every time you draw it. You can store a 1 pixel bitmap for the lifetime of the application and just copy it over and over.

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