NEAREST API CALL
When the BkMode is set to OPAQUE, the color that SETBKCOLOR sets is the
color that will be used as the background color for
the box that is the background to text.
the color that shows through the transparent areas of hatched brushes and
styled (dashed) lines.
and for the background color when converting bitmaps to monochrome and
vice versa, though i havent figured out if this last point has any revelence
to a metafile converter.