NAME

colortab, colorn - define color lookup table for MEGAPIC graphic

SYNOPSIS

#include <mpict_p.h>

colortab(carg)
struct color carg[NCOLOR];

colorn(cnum, red, green, blue)
int cnum;
unsigned red, green, blue;

DESCRIPTION

colortab
colortab defines the entries in the color lookup table for the megapic graphics facility. The color lookup table proviedes up to 16 different colors (with the current Megatek hardware only the even numbered entries are available, limiting the number of different colors to 8). Each color is defined by a mix of red, green and blue intensities ranging from 0 to 15. carg is a pointer to an array of NCOLOR(16) color structures of the following form:
struct color {
  unsigned red;
  unsigned blue;
  unsigned green;
};
Each field specifies a value of red, blue or green intensity. Each element of the array specifies one entry in the color lookup table. On initialization, the color lookup table contains the following:
0,0,0
1,1,1
2,2,2
3,3,3
4,4,4
5,5,5
6,6,6
7,7,7
8,8,8
9,9,9
10,10,10
11,11,11
12,12,12
13,13,13
14,14,14
15,15,15
colorn
colorn defines a single entry of the color lookup table, indexed by cnum. red, green, blue specify the intensities for the red, green, and blue components ranging from 0 to 15.

SEE ALSO

chpar(3U)

DIAGNOSTICS

colortab and colorn both print an error message and return -1 if given an illegal intensity. colorn prints an error message and returns -1 if given an illegal color index.