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_SetBkColor Procedure
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Argument
color Specifies background color
Description
The _SetBkColor procedure sets the current background color to the
color specified in the LongInt parameter color. The background color
cannot be changed in _HResBW or _OResColor modes.
In a text mode (such as _TextC80), _SetBkColor accepts and
_GetBkColor returns a color index. For example, _SetBkColor( 2 )
sets the background color to color index 2. The actual color
displayed depends on the palette mapping for color index 2. The
default color value for color index 2 is green in a color text
mode.
In a color graphics mode (such as _EResColor), _SetBkColor
accepts and _GetBkColor returns a color value (as used in
_RemapPalette). The value for the background color can be given
by the color constants defined in MSGraph. For example,
_SetBkColor( _Green ) sets the background color in a color graphics
mode to green. These constants are provided for convenience in
working with the most common colors. The actual range of colors
available is generally much greater. Other constants are available
for the monochrome graphics mode, _EResNoColor. In _EResNoColor mode,
only 0 through 8 are valid background color values. See MSGraph for
definitions of these constants.
When a color argument is of type LongInt, it generally refers to a
color value, and when it is of type Integer, it refers to an
attribute or color index. _SetBkColor and _GetBkColor are
exceptions: the argument is a color index in text modes and
a color value in graphics modes. A more complete discussion of
colors is given in the description of the _RemapPalette function.
_RemapPalette can also be used to set the background color in
graphics modes. The background color has a color index of 0.
Unlike _RemapPalette, however, _SetBkColor does not require an
EGA, MCGA, or VGA environment.
In a text mode, _SetBkColor affects subsequent output, but does not
change the current display. In a graphics mode, it immediately
changes the appearance of all background pixels.
_GrStatus Returns
_GrInvalidParameter, _GrParameterAltered