/* $OpenBSD: colour.c,v 1.14 2016/07/15 00:42:56 nicm Exp $ */ /* * Copyright (c) 2008 Nicholas Marriott * Copyright (c) 2016 Avi Halachmi * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include #include #include #include #include "tmux.h" static int colour_dist_sq(int R, int G, int B, int r, int g, int b) { return ((R - r) * (R - r) + (G - g) * (G - g) + (B - b) * (B - b)); } static int colour_to_6cube(int v) { if (v < 48) return (0); if (v < 114) return (1); return ((v - 35) / 40); } /* * Convert an RGB triplet to the xterm(1) 256 colour palette. * * xterm provides a 6x6x6 colour cube (16 - 231) and 24 greys (232 - 255). We * map our RGB colour to the closest in the cube, also work out the closest * grey, and use the nearest of the two. * * Note that the xterm has much lower resolution for darker colors (they are * not evenly spread out), so our 6 levels are not evenly spread: 0x0, 0x5f * (95), 0x87 (135), 0xaf (175), 0xd7 (215) and 0xff (255). Greys are more * evenly spread (8, 18, 28 ... 238). */ int colour_find_rgb(u_char r, u_char g, u_char b) { static const int q2c[6] = { 0x00, 0x5f, 0x87, 0xaf, 0xd7, 0xff }; int qr, qg, qb, cr, cg, cb, d, idx; int grey_avg, grey_idx, grey; /* Map RGB to 6x6x6 cube. */ qr = colour_to_6cube(r); cr = q2c[qr]; qg = colour_to_6cube(g); cg = q2c[qg]; qb = colour_to_6cube(b); cb = q2c[qb]; /* If we have hit the colour exactly, return early. */ if (cr == r && cg == g && cb == b) return ((16 + (36 * qr) + (6 * qg) + qb) | COLOUR_FLAG_256); /* Work out the closest grey (average of RGB). */ grey_avg = (r + g + b) / 3; if (grey_avg > 238) grey_idx = 23; else grey_idx = (grey_avg - 3) / 10; grey = 8 + (10 * grey_idx); /* Is grey or 6x6x6 colour closest? */ d = colour_dist_sq(cr, cg, cb, r, g, b); if (colour_dist_sq(grey, grey, grey, r, g, b) < d) idx = 232 + grey_idx; else idx = 16 + (36 * qr) + (6 * qg) + qb; return (idx | COLOUR_FLAG_256); } /* Join RGB into a colour. */ int colour_join_rgb(u_char r, u_char g, u_char b) { return ((((int)((r) & 0xff)) << 16) | (((int)((g) & 0xff)) << 8) | (((int)((b) & 0xff))) | COLOUR_FLAG_RGB); } /* Split colour into RGB. */ void colour_split_rgb(int c, u_char *r, u_char *g, u_char *b) { *r = (c >> 16) & 0xff; *g = (c >> 8) & 0xff; *b = c & 0xff; } /* Convert colour to a string. */ const char * colour_tostring(int c) { static char s[32]; u_char r, g, b; if (c & COLOUR_FLAG_RGB) { colour_split_rgb(c, &r, &g, &b); xsnprintf(s, sizeof s, "#%02x%02x%02x", r, g, b); return (s); } if (c & COLOUR_FLAG_256) { xsnprintf(s, sizeof s, "colour%u", c & 0xff); return (s); } switch (c) { case 0: return ("black"); case 1: return ("red"); case 2: return ("green"); case 3: return ("yellow"); case 4: return ("blue"); case 5: return ("magenta"); case 6: return ("cyan"); case 7: return ("white"); case 8: return ("default"); case 90: return ("brightblack"); case 91: return ("brightred"); case 92: return ("brightgreen"); case 93: return ("brightyellow"); case 94: return ("brightblue"); case 95: return ("brightmagenta"); case 96: return ("brightcyan"); case 97: return ("brightwhite"); } return (NULL); } /* Convert colour from string. */ int colour_fromstring(const char *s) { const char *errstr; const char *cp; int n; u_char r, g, b; if (*s == '#' && strlen(s) == 7) { for (cp = s + 1; isxdigit((u_char) *cp); cp++) ; if (*cp != '\0') return (-1); n = sscanf(s + 1, "%2hhx%2hhx%2hhx", &r, &g, &b); if (n != 3) return (-1); return (colour_join_rgb(r, g, b)); } if (strncasecmp(s, "colour", (sizeof "colour") - 1) == 0) { n = strtonum(s + (sizeof "colour") - 1, 0, 255, &errstr); if (errstr != NULL) return (-1); return (n | COLOUR_FLAG_256); } if (strcasecmp(s, "black") == 0 || strcmp(s, "0") == 0) return (0); if (strcasecmp(s, "red") == 0 || strcmp(s, "1") == 0) return (1); if (strcasecmp(s, "green") == 0 || strcmp(s, "2") == 0) return (2); if (strcasecmp(s, "yellow") == 0 || strcmp(s, "3") == 0) return (3); if (strcasecmp(s, "blue") == 0 || strcmp(s, "4") == 0) return (4); if (strcasecmp(s, "magenta") == 0 || strcmp(s, "5") == 0) return (5); if (strcasecmp(s, "cyan") == 0 || strcmp(s, "6") == 0) return (6); if (strcasecmp(s, "white") == 0 || strcmp(s, "7") == 0) return (7); if (strcasecmp(s, "default") == 0 || strcmp(s, "8") == 0) return (8); if (strcasecmp(s, "brightblack") == 0 || strcmp(s, "90") == 0) return (90); if (strcasecmp(s, "brightred") == 0 || strcmp(s, "91") == 0) return (91); if (strcasecmp(s, "brightgreen") == 0 || strcmp(s, "92") == 0) return (92); if (strcasecmp(s, "brightyellow") == 0 || strcmp(s, "93") == 0) return (93); if (strcasecmp(s, "brightblue") == 0 || strcmp(s, "94") == 0) return (94); if (strcasecmp(s, "brightmagenta") == 0 || strcmp(s, "95") == 0) return (95); if (strcasecmp(s, "brightcyan") == 0 || strcmp(s, "96") == 0) return (96); if (strcasecmp(s, "brightwhite") == 0 || strcmp(s, "97") == 0) return (97); return (-1); } /* Convert 256 colour palette to 16. */ u_char colour_256to16(u_char c) { static const u_char table[256] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 4, 4, 4, 12, 12, 2, 6, 4, 4, 12, 12, 2, 2, 6, 4, 12, 12, 2, 2, 2, 6, 12, 12, 10, 10, 10, 10, 14, 12, 10, 10, 10, 10, 10, 14, 1, 5, 4, 4, 12, 12, 3, 8, 4, 4, 12, 12, 2, 2, 6, 4, 12, 12, 2, 2, 2, 6, 12, 12, 10, 10, 10, 10, 14, 12, 10, 10, 10, 10, 10, 14, 1, 1, 5, 4, 12, 12, 1, 1, 5, 4, 12, 12, 3, 3, 8, 4, 12, 12, 2, 2, 2, 6, 12, 12, 10, 10, 10, 10, 14, 12, 10, 10, 10, 10, 10, 14, 1, 1, 1, 5, 12, 12, 1, 1, 1, 5, 12, 12, 1, 1, 1, 5, 12, 12, 3, 3, 3, 7, 12, 12, 10, 10, 10, 10, 14, 12, 10, 10, 10, 10, 10, 14, 9, 9, 9, 9, 13, 12, 9, 9, 9, 9, 13, 12, 9, 9, 9, 9, 13, 12, 9, 9, 9, 9, 13, 12, 11, 11, 11, 11, 7, 12, 10, 10, 10, 10, 10, 14, 9, 9, 9, 9, 9, 13, 9, 9, 9, 9, 9, 13, 9, 9, 9, 9, 9, 13, 9, 9, 9, 9, 9, 13, 9, 9, 9, 9, 9, 13, 11, 11, 11, 11, 11, 15, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 7, 7, 7, 7, 7, 7, 15, 15, 15, 15, 15, 15 }; return (table[c]); }