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NAMEcmap2rgb, cmap2rgba, rgb2cmap - colors and color mapsSYNOPSIS#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) DESCRIPTIONThese routines convert between `true color' red/green/blue triples and the Plan 9 color map. See 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 and library routines that take colors as arguments. SOURCE/src/libdrawSEE ALSO Visit the GSP FreeBSD Man Page Interface. |