xref: /openbsd-src/lib/libcurses/base/lib_color.c (revision 4b107ee47ccf17c9f1ad6db8a59eb142776341c8)
1 /*	$OpenBSD: lib_color.c,v 1.6 2000/03/10 01:35:02 millert Exp $	*/
2 
3 /****************************************************************************
4  * Copyright (c) 1998,1999,2000 Free Software Foundation, Inc.              *
5  *                                                                          *
6  * Permission is hereby granted, free of charge, to any person obtaining a  *
7  * copy of this software and associated documentation files (the            *
8  * "Software"), to deal in the Software without restriction, including      *
9  * without limitation the rights to use, copy, modify, merge, publish,      *
10  * distribute, distribute with modifications, sublicense, and/or sell       *
11  * copies of the Software, and to permit persons to whom the Software is    *
12  * furnished to do so, subject to the following conditions:                 *
13  *                                                                          *
14  * The above copyright notice and this permission notice shall be included  *
15  * in all copies or substantial portions of the Software.                   *
16  *                                                                          *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
20  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
21  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
22  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
23  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
24  *                                                                          *
25  * Except as contained in this notice, the name(s) of the above copyright   *
26  * holders shall not be used in advertising or otherwise to promote the     *
27  * sale, use or other dealings in this Software without prior written       *
28  * authorization.                                                           *
29  ****************************************************************************/
30 
31 /****************************************************************************
32  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
33  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
34  ****************************************************************************/
35 
36 /* lib_color.c
37  *
38  * Handles color emulation of SYS V curses
39  */
40 
41 #include <curses.priv.h>
42 
43 #include <term.h>
44 #include <tic.h>
45 
46 MODULE_ID("$From: lib_color.c,v 1.45 2000/02/27 00:20:31 tom Exp $")
47 
48 /*
49  * These should be screen structure members.  They need to be globals for
50  * historical reasons.  So we assign them in start_color() and also in
51  * set_term()'s screen-switching logic.
52  */
53 int COLOR_PAIRS = 0;
54 int COLORS = 0;
55 
56 /*
57  * Given a RGB range of 0..1000, we'll normally set the individual values
58  * to about 2/3 of the maximum, leaving full-range for bold/bright colors.
59  */
60 #define RGB_ON  680
61 #define RGB_OFF 0
62 /* *INDENT-OFF* */
63 static const color_t cga_palette[] =
64 {
65     /*  R               G               B */
66     {RGB_OFF,		RGB_OFF,	RGB_OFF},	/* COLOR_BLACK */
67     {RGB_ON,		RGB_OFF,	RGB_OFF},	/* COLOR_RED */
68     {RGB_OFF,		RGB_ON,		RGB_OFF},	/* COLOR_GREEN */
69     {RGB_ON,		RGB_ON,		RGB_OFF},	/* COLOR_YELLOW */
70     {RGB_OFF,		RGB_OFF,	RGB_ON},	/* COLOR_BLUE */
71     {RGB_ON,		RGB_OFF,	RGB_ON},	/* COLOR_MAGENTA */
72     {RGB_OFF,		RGB_ON,		RGB_ON},	/* COLOR_CYAN */
73     {RGB_ON,		RGB_ON,		RGB_ON},	/* COLOR_WHITE */
74 };
75 
76 static const color_t hls_palette[] =
77 {
78     /*  H       L       S */
79     {	0,	0,	0},		/* COLOR_BLACK */
80     {	120,	50,	100},		/* COLOR_RED */
81     {	240,	50,	100},		/* COLOR_GREEN */
82     {	180,	50,	100},		/* COLOR_YELLOW */
83     {	330,	50,	100},		/* COLOR_BLUE */
84     {	60,	50,	100},		/* COLOR_MAGENTA */
85     {	300,	50,	100},		/* COLOR_CYAN */
86     {	0,	50,	100},		/* COLOR_WHITE */
87 };
88 /* *INDENT-ON* */
89 
90 #ifdef NCURSES_EXT_FUNCS
91 static int
92 default_fg(void)
93 {
94     return (SP->_default_fg != C_MASK) ? SP->_default_fg : COLOR_WHITE;
95 }
96 
97 static int
98 default_bg(void)
99 {
100     return (SP->_default_bg != C_MASK) ? SP->_default_bg : COLOR_BLACK;
101 }
102 #else
103 #define default_fg() COLOR_WHITE
104 #define default_bg() COLOR_BLACK
105 #endif
106 
107 /*
108  * SVr4 curses is known to interchange color codes (1,4) and (3,6), possibly
109  * to maintain compatibility with a pre-ANSI scheme.  The same scheme is
110  * also used in the FreeBSD syscons.
111  */
112 static int
113 toggled_colors(int c)
114 {
115     if (c < 16) {
116 	static const int table[] =
117 	{0, 4, 2, 6, 1, 5, 3, 7,
118 	    8, 12, 10, 14, 9, 13, 11, 15};
119 	c = table[c];
120     }
121     return c;
122 }
123 
124 static void
125 set_background_color(int bg, int (*outc) (int))
126 {
127     if (set_a_background) {
128 	TPUTS_TRACE("set_a_background");
129 	tputs(tparm(set_a_background, bg), 1, outc);
130     } else {
131 	TPUTS_TRACE("set_background");
132 	tputs(tparm(set_background, toggled_colors(bg)), 1, outc);
133     }
134 }
135 
136 static void
137 set_foreground_color(int fg, int (*outc) (int))
138 {
139     if (set_a_foreground) {
140 	TPUTS_TRACE("set_a_foreground");
141 	tputs(tparm(set_a_foreground, fg), 1, outc);
142     } else {
143 	TPUTS_TRACE("set_foreground");
144 	tputs(tparm(set_foreground, toggled_colors(fg)), 1, outc);
145     }
146 }
147 
148 static bool
149 set_original_colors(void)
150 {
151     if (orig_pair != 0) {
152 	TPUTS_TRACE("orig_pair");
153 	putp(orig_pair);
154 	return TRUE;
155     } else if (orig_colors != NULL) {
156 	TPUTS_TRACE("orig_colors");
157 	putp(orig_colors);
158 	return TRUE;
159     }
160     return FALSE;
161 }
162 
163 int
164 start_color(void)
165 {
166     int n;
167     const color_t *tp;
168 
169     T((T_CALLED("start_color()")));
170 
171     if (set_original_colors() != TRUE) {
172 	set_foreground_color(default_fg(), _nc_outch);
173 	set_background_color(default_bg(), _nc_outch);
174     }
175 
176     if (VALID_NUMERIC(max_pairs))
177 	COLOR_PAIRS = SP->_pair_count = max_pairs;
178     else
179 	returnCode(ERR);
180     if ((SP->_color_pairs = typeCalloc(unsigned short, max_pairs)) == 0)
181 	  returnCode(ERR);
182     SP->_color_pairs[0] = PAIR_OF(default_fg(), default_bg());
183     if (VALID_NUMERIC(max_colors))
184 	COLORS = SP->_color_count = max_colors;
185     else
186 	returnCode(ERR);
187     SP->_coloron = 1;
188 
189     if ((SP->_color_table = typeMalloc(color_t, COLORS)) == 0)
190 	returnCode(ERR);
191     tp = (hue_lightness_saturation) ? hls_palette : cga_palette;
192     for (n = 0; n < COLORS; n++) {
193 	if (n < 8) {
194 	    SP->_color_table[n] = tp[n];
195 	} else {
196 	    SP->_color_table[n] = tp[n % 8];
197 	    if (hue_lightness_saturation) {
198 		SP->_color_table[n].green = 100;
199 	    } else {
200 		if (SP->_color_table[n].red)
201 		    SP->_color_table[n].red = 1000;
202 		if (SP->_color_table[n].green)
203 		    SP->_color_table[n].green = 1000;
204 		if (SP->_color_table[n].blue)
205 		    SP->_color_table[n].blue = 1000;
206 	    }
207 	}
208     }
209 
210     T(("started color: COLORS = %d, COLOR_PAIRS = %d", COLORS, COLOR_PAIRS));
211 
212     returnCode(OK);
213 }
214 
215 /* This function was originally written by Daniel Weaver <danw@znyx.com> */
216 static void
217 rgb2hls(short r, short g, short b, short *h, short *l, short *s)
218 /* convert RGB to HLS system */
219 {
220     short min, max, t;
221 
222     if ((min = g < r ? g : r) > b)
223 	min = b;
224     if ((max = g > r ? g : r) < b)
225 	max = b;
226 
227     /* calculate lightness */
228     *l = (min + max) / 20;
229 
230     if (min == max) {		/* black, white and all shades of gray */
231 	*h = 0;
232 	*s = 0;
233 	return;
234     }
235 
236     /* calculate saturation */
237     if (*l < 50)
238 	*s = ((max - min) * 100) / (max + min);
239     else
240 	*s = ((max - min) * 100) / (2000 - max - min);
241 
242     /* calculate hue */
243     if (r == max)
244 	t = 120 + ((g - b) * 60) / (max - min);
245     else if (g == max)
246 	t = 240 + ((b - r) * 60) / (max - min);
247     else
248 	t = 360 + ((r - g) * 60) / (max - min);
249 
250     *h = t % 360;
251 }
252 
253 /*
254  * Extension (1997/1/18) - Allow negative f/b values to set default color
255  * values.
256  */
257 int
258 init_pair(short pair, short f, short b)
259 {
260     unsigned result;
261 
262     T((T_CALLED("init_pair(%d,%d,%d)"), pair, f, b));
263 
264     if ((pair < 1) || (pair >= COLOR_PAIRS))
265 	returnCode(ERR);
266 #ifdef NCURSES_EXT_FUNCS
267     if (SP->_default_color) {
268 	if (f < 0)
269 	    f = C_MASK;
270 	if (b < 0)
271 	    b = C_MASK;
272 	if (f >= COLORS && f != C_MASK)
273 	    returnCode(ERR);
274 	if (b >= COLORS && b != C_MASK)
275 	    returnCode(ERR);
276     } else
277 #endif
278 	if ((f < 0) || (f >= COLORS)
279 	|| (b < 0) || (b >= COLORS))
280 	returnCode(ERR);
281 
282     /*
283      * When a pair's content is changed, replace its colors (if pair was
284      * initialized before a screen update is performed replacing original
285      * pair colors with the new ones).
286      */
287     result = PAIR_OF(f, b);
288     if (SP->_color_pairs[pair] != 0
289 	&& SP->_color_pairs[pair] != result) {
290 	int y, x;
291 	attr_t z = COLOR_PAIR(pair);
292 
293 	for (y = 0; y <= curscr->_maxy; y++) {
294 	    struct ldat *ptr = &(curscr->_line[y]);
295 	    bool changed = FALSE;
296 	    for (x = 0; x <= curscr->_maxx; x++) {
297 		if ((ptr->text[x] & A_COLOR) == z) {
298 		    /* Set the old cell to zero to ensure it will be
299 		       updated on the next doupdate() */
300 		    ptr->text[x] = 0;
301 		    CHANGED_CELL(ptr, x);
302 		    changed = TRUE;
303 		}
304 	    }
305 	    if (changed)
306 		_nc_make_oldhash(y);
307 	}
308     }
309     SP->_color_pairs[pair] = result;
310 
311     if (initialize_pair) {
312 	const color_t *tp = hue_lightness_saturation ? hls_palette : cga_palette;
313 
314 	T(("initializing pair: pair = %d, fg=(%d,%d,%d), bg=(%d,%d,%d)",
315 		pair,
316 		tp[f].red, tp[f].green, tp[f].blue,
317 		tp[b].red, tp[b].green, tp[b].blue));
318 
319 	if (initialize_pair) {
320 	    TPUTS_TRACE("initialize_pair");
321 	    putp(tparm(initialize_pair,
322 		    pair,
323 		    tp[f].red, tp[f].green, tp[f].blue,
324 		    tp[b].red, tp[b].green, tp[b].blue));
325 	}
326     }
327 
328     returnCode(OK);
329 }
330 
331 int
332 init_color(short color, short r, short g, short b)
333 {
334     T((T_CALLED("init_color(%d,%d,%d,%d)"), color, r, g, b));
335 
336     if (initialize_color == NULL)
337 	returnCode(ERR);
338 
339     if (color < 0 || color >= COLORS)
340 	returnCode(ERR);
341     if (r < 0 || r > 1000 || g < 0 || g > 1000 || b < 0 || b > 1000)
342 	returnCode(ERR);
343 
344     if (hue_lightness_saturation)
345 	rgb2hls(r, g, b,
346 	    &SP->_color_table[color].red,
347 	    &SP->_color_table[color].green,
348 	    &SP->_color_table[color].blue);
349     else {
350 	SP->_color_table[color].red = r;
351 	SP->_color_table[color].green = g;
352 	SP->_color_table[color].blue = b;
353     }
354 
355     if (initialize_color) {
356 	TPUTS_TRACE("initialize_color");
357 	putp(tparm(initialize_color, color, r, g, b));
358     }
359     returnCode(OK);
360 }
361 
362 bool
363 can_change_color(void)
364 {
365     T((T_CALLED("can_change_color()")));
366     returnCode((can_change != 0) ? TRUE : FALSE);
367 }
368 
369 bool
370 has_colors(void)
371 {
372     T((T_CALLED("has_colors()")));
373     returnCode((VALID_NUMERIC(max_colors) && VALID_NUMERIC(max_pairs)
374 	    && (((set_foreground != NULL)
375 		    && (set_background != NULL))
376 		|| ((set_a_foreground != NULL)
377 		    && (set_a_background != NULL))
378 		|| set_color_pair)) ? TRUE : FALSE);
379 }
380 
381 int
382 color_content(short color, short *r, short *g, short *b)
383 {
384     T((T_CALLED("color_content(%d,%p,%p,%p)"), color, r, g, b));
385     if (color < 0 || color >= COLORS)
386 	returnCode(ERR);
387 
388     if (r)
389 	*r = SP->_color_table[color].red;
390     if (g)
391 	*g = SP->_color_table[color].green;
392     if (b)
393 	*b = SP->_color_table[color].blue;
394     returnCode(OK);
395 }
396 
397 int
398 pair_content(short pair, short *f, short *b)
399 {
400     T((T_CALLED("pair_content(%d,%p,%p)"), pair, f, b));
401 
402     if ((pair < 0) || (pair >= COLOR_PAIRS))
403 	returnCode(ERR);
404     if (f)
405 	*f = ((SP->_color_pairs[pair] >> C_SHIFT) & C_MASK);
406     if (b)
407 	*b = (SP->_color_pairs[pair] & C_MASK);
408 
409     returnCode(OK);
410 }
411 
412 void
413 _nc_do_color(int pair, bool reverse, int (*outc) (int))
414 {
415     short fg, bg;
416 
417     if (pair == 0) {
418 	if (
419 #ifdef NCURSES_EXT_FUNCS
420 	    !SP->_default_color ||
421 #endif
422 	    !set_original_colors()) {
423 	    fg = default_fg();
424 	    bg = default_bg();
425 	} else {
426 	    fg = C_MASK;
427 	    bg = C_MASK;
428 	}
429     } else {
430 	if (set_color_pair) {
431 	    TPUTS_TRACE("set_color_pair");
432 	    tputs(tparm(set_color_pair, pair), 1, outc);
433 	    return;
434 	} else {
435 	    pair_content(pair, &fg, &bg);
436 #ifdef NCURSES_EXT_FUNCS
437 	    if (SP->_default_color) {
438 		if (fg == C_MASK)
439 		    fg = SP->_default_fg;
440 		if (bg == C_MASK)
441 		    bg = SP->_default_bg;
442 	    }
443 #endif
444 	}
445     }
446 
447     if (fg == C_MASK || bg == C_MASK) {
448 	if (set_original_colors() != TRUE) {
449 	    if (fg == C_MASK)
450 		fg = default_fg();
451 	    if (bg == C_MASK)
452 		bg = default_bg();
453 	}
454     }
455 
456     if (reverse) {
457 	short xx = fg;
458 	fg = bg;
459 	bg = xx;
460     }
461 
462     T(("setting colors: pair = %d, fg = %d, bg = %d", pair, fg, bg));
463 
464     if (fg != C_MASK) {
465 	set_foreground_color(fg, outc);
466     }
467     if (bg != C_MASK) {
468 	set_background_color(bg, outc);
469     }
470 }
471