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 NAME     
 |  |  |  | cmap2rgb, cmap2rgba, rgb2cmap – colors and color maps 
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 SYNOPSIS     
 |  |  |  | #include <u.h> #include <libc.h>
 #include <draw.h> 
    
    
    int    rgb2cmap(int red, int green, int blue) 
    
    
    int    cmap2rgb(int col) 
    
    
    int    cmap2rgba(int col)
 
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 DESCRIPTION     
 |  |  |  | These routines convert between ‘true color’ red/green/blue triples
    and the Plan 9 color map. See color(7) for a description of RGBV,
    the standard color map. 
    
    
    Rgb2cmap takes a trio of color values, scaled from 0 (no intensity)
    to 255 (full intensity), and returns the index of the color in
    RGBV closest to that represented by those values. 
    
    
    Cmap2rgb decomposes the color of RGBV index col and returns a
    24-bit integer with the low 8 bits representing the blue value,
    the next 8 representing green, and the next 8 representing red.
    Cmap2rgba decomposes the color of RGBV index col and returns a
    32-bit integer with the low 8 bits representing an alpha value,
    defined to be 255, and the next
    8 representing blue, then green, then red, as for cmap2rgba shifted
    up 8 bits. This 32-bit representation is the format used by draw(3)
    and memdraw(3) library routines that take colors as arguments. 
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 SOURCE     
 SEE ALSO    
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