cms_grays.h

操作系统SunOS 4.1.3版本的源码

/*	@(#)cms_grays.h 1.1 92/07/30 SMI	*/

/*
 * Copyright (c) 1983 by Sun Microsystems, Inc.
 */

/*
 * Definition of the colormap segment CMS_GRAYS, a collection of grays.
 */

#define	CMS_GRAYS	"grays"
#define	CMS_GRAYSSIZE	8

#define	WHITE	0
#define	GRAY(i)	((BLACK)*(i)/100)
#define	BLACK	7

#define	cms_grayssetup(r,g,b) \
	{ unsigned char v = 0, vi; \
	  int	i, gi; \
	  vi = 255/BLACK; \
	  for (i=BLACK-1;i>WHITE;i--) { /* Dark (small v)->light (large v) */ \
		v += vi; \
		gi = GRAY(100/8*i); \
		(r)[gi] = v; (g)[gi] = v; (b)[gi] = v;  \
	  } \
	  (r)[WHITE] = 255;	(g)[WHITE] = 255;	(b)[WHITE] = 255; \
	  (r)[BLACK] = 0;	(g)[BLACK] = 0;		(b)[BLACK] = 0; \
	}