blink(3G)

NAME
     blink - changes a color map entry at a selectable rate

FORTRAN 77 SPECIFICATION
     subroutine blink(rate, i, red, green, blue)
     integer*4 rate, i, red, green, blue

PARAMETERS
     rate    expects the number of vertical retraces per blink.  On the
             standard monitor, there are 60 vertical retraces per second.

     i       expects an index into the current color map.  The color defined
             at that index is the color that is blinked (alternated).

     red     expects the red value of the alternate color that blinks against
             the color selected from the color map by the i parameter.

     green   expects the green value of the alternate color that blinks
             against the color selected from the color map by the i parameter.

     blue    expects the blue value of the alternate color that blinks against
             the color selected from the color map by the i parameter.

DESCRIPTION
     blink alternates the color located at index i in the current color map
     with the color defined by the parameters red, green, and blue. The rate
     at which the two colors are alternated is set by the rate parameter. The
     maximum number of color map entries that can be blinking simultaneously
     on a screen is returned by the getgde inquiry GBNBLI.

     The length of time between retraces varies according to the monitor used.
     On the standard monitor, there are 60 retraces per second, so a rate of
     60 would cause the color to change once every second.

     To terminate blinking and restore the original color for a single color
     map entry, call blink for that entry with rate set to 0.

     To terminate all blinking colors simultaneously, call blink with rate set
     to -1.  When rate is -1, the other parameters are ignored.

SEE ALSO
     getgde, mapcol

NOTES
     This routine is available only in immediate mode.

BUGS
     blink always operates on the colormap of the normal framebuffer,
     regardless of the current drawmode.  It is not possible to blink overlay
     or underlay colors.