BACKGROUND_COLOR(3G)

NAME

background_color − set the background color by color table index or color value. Background color is painted by clear_view_surface.

SYNOPSIS

C SYNTAX

void background_color_index(fildes,index);
int fildes,index;

void background_color(fildes,red,green,blue);
int fildes;
float red,green,blue;

FORTRAN77 SYNTAX

        subroutine background_color_index(fildes,index)
        integer*4 fildes,index

        subroutine background_color(fildes,red,green,blue)
        integer*4 fildes
        real red,green,blue

PASCAL SYNTAX

procedure background_color_index(fildes,index:integer);

procedure background_color(fildes:integer;
red,green,blue:real);

HP-UX COMPATIBILITY

Level: HP-UX/STANDARD

Origin: HP

DESCRIPTION

INPUT PARAMETERS

fildes
an integer file descriptor returned by gopen when an I/O path to a graphic device is opened.
index
an integer index into the device color table. The background color is the red, green and blue values specified at this table location.
red,green,blue
are the color values (in the range of 0.0 to 1.0) to be used for the background color. Zero (0.0) indicates no color and one (1.0) indicates full color. Monochrome devices use the equation I=0.30*red+0.59*green+0.11*blue to determine the intensity.

DISCUSSION

When the background color is specified with red, green and blue parameters, the color table is searched for an index which points to the closest color in RGB space to the one specified. The background will be repainted with the specified index by subsequent clear_view_surface commands. The area repainted is selected by clear_control and can be either:

      the Virtual Device Coordinate area

      the clip rectangle area

      the entire display

If fildes specifies a hard copy device, the background color cannot be changed.

DEFAULTS

Color index 0 (zero).

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