cpack(3G)

NAME
     cpack - specifies RGBA color with a single packed 32-bit integer

C SPECIFICATION
     void cpack(pack)
     unsigned long pack;

PARAMETERS
     pack   expects a packed integer containing the RGBA (red, green, blue,
            alpha) values you want to assign as the current color. Expressed
            in hexadecimal, the format of the packed integer is 0xaabbggrr,
            where:

               aa   is the alpha value,
               bb   is the blue value,
               gg   is the green value, and
               rr   is the red value.

            RGBA component values range from 0 to 0xFF (255).

DESCRIPTION
     cpack sets the red, green, blue, and alpha color components of the
     currently active GL framebuffer, one of normal, popup, overlay, or
     underlay (see drawmode).  The current framebuffer must be in RGB mode
     (see RGBmode) for the cpack command to be applicable.  Most drawing
     commands copy the current RGBA color components into the color bitplanes
     of the current framebuffer.  Color components are retained in each draw
     mode, so when a draw mode is re-entered, red, green, blue, and alpha are
     reset to the last value specified in that draw mode.

     Color component values range from 0, specifying no intensity, through
     255, specifying maximum intensity.  For example, cpack(0xFF004080) sets
     red to 0x80 (half intensity), green to 0x40 (quarter intensity), blue to
     0 (off), and alpha to 0xFF (full intensity).

     It is an error to call cpack while the current framebuffer is in color
     map mode.

     The color components of all framebuffers in RGB mode are set to zero when
     gconfig is called.

SEE ALSO
     c, drawmode, gRGBcolor, lmcolor

NOTE
     cpack can also be used to modify the current material while lighting is
     active (see lmcolor).

     Because only the normal framebuffer currently supports RGB mode, cpack
     should be called only while draw mode is NORMALDRAW.  Use getgdesc to
     determine whether RGB mode is available in draw mode NORMALDRAW.