CIGAL Reference Manual, Chapter 6 (RealTime): r_erase
usage: r_erase opflg eflag ltime [Value]
R_ERASE is a REALTIME operator. It sets all pixels in the screen display to a single value. If VALUE is specified, it is used as the new pixel intensity. Otherwise, the current background intensity (see R_COLOR(6) or R_RGBCOLOR(6)) is used.
See Also:
R_COLOR(6),
R_RGBCOLOR(6)