The key is that you have to calculate the ascent height of the font. The font ascent as reported by FontFamily.GetCellAscent is in what is called ’Design Units’. The Cell Spacing design unit value of fonts is proportional to the actual height of the font on the device. We use this relationship to calculate cell ascent in device units.
The rendering code has to just ensure that the x, y position passed to DrawString takes care of the ascent.