NAME
    SetRGB4CM -- Set one color register for this ColorMap.
SYNOPSIS
    SetRGB4CM(  cm,  n,   r,    g,    b)
                a0  d0  d1:4  d2:4  d3:4
    void SetRGB4CM( struct ColorMap *, SHORT, UBYTE, UBYTE, UBYTE );
INPUTS
    cm = colormap
    n = the number of the color register to set. Ranges from 0 to 31
         on current amiga displays.
    r = red level (0-15)
    g = green level (0-15)
    b = blue level (0-15)
RESULT
    Store the (r,g,b) triplet at index n of the ColorMap structure.
    This function can be used to set up a ColorMap before before
    linking it into a viewport.
BUGS
SEE ALSO
    GetColorMap() GetRGB4() SetRGB4() graphics/view.h