2 * Functions necessary to display a deck of slides in different color modes
3 * using ncurses. Only white, red, and blue are supported, as they can be
4 * faded in 256 color mode.
5 * Copyright (C) 2016 Michael Goehler
7 * This file is part of mdp.
9 * This program is free software: you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation, either version 3 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program. If not, see <http://www.gnu.org/licenses/>.
24 #include <ctype.h> // isalnum
25 #include <wchar.h> // wcschr
26 #include <wctype.h> // iswalnum
27 #include <string.h> // strcpy
28 #include <unistd.h> // usleep
31 // color ramp for fading from black to color
32 static short white_ramp[24] = { 16, 232, 233, 234, 235, 236,
33 237, 238, 239, 240, 241, 242,
34 244, 245, 246, 247, 248, 249,
35 250, 251, 252, 253, 254, 255 };
37 static short blue_ramp[24] = { 16, 17, 17, 18, 18, 19,
38 19, 20, 20, 21, 27, 33,
39 32, 39, 38, 45, 44, 44,
40 81, 81, 51, 51, 123, 123 };
42 static short red_ramp[24] = { 16, 52, 52, 53, 53, 89,
43 89, 90, 90, 126, 127, 127,
44 163, 163, 164, 164, 200, 200,
45 201, 201, 207, 207, 213, 213 };
47 // color ramp for fading from white to color
48 static short white_ramp_invert[24] = { 15, 255, 254, 254, 252, 251,
49 250, 249, 248, 247, 246, 245,
50 243, 242, 241, 240, 239, 238,
51 237, 236, 235, 234, 233, 232};
53 static short blue_ramp_invert[24] = { 15, 231, 231, 195, 195, 159,
54 159, 123, 123, 87, 51, 44,
55 45, 38, 39, 32, 33, 33,
56 26, 26, 27, 27, 21, 21};
58 static short red_ramp_invert[24] = { 15, 231, 231, 224, 224, 225,
59 225, 218, 218, 219, 212, 213,
60 206, 207, 201, 200, 199, 199,
61 198, 198, 197, 197, 196, 196};
63 int ncurses_display(deck_t *deck, int notrans, int nofade, int invert, int reload, int noreload, int slidenum) {
67 int l = 0; // line number
68 int lc = 0; // line count
69 int sc = 1; // slide count
70 int colors = 0; // amount of colors supported
71 int fade = 0; // disable color fading by default
72 int trans = -1; // enable transparency if term supports it
73 int max_lines = 0; // max lines per slide
74 int max_cols = 0; // max columns per line
75 int offset; // text offset
76 int stop = 0; // passed stop bits per slide
78 // header line 1 is displayed at the top
79 int bar_top = (deck->headers > 0) ? 1 : 0;
80 // header line 2 is displayed at the bottom
81 // anyway we display the slide number at the bottom
82 int bar_bottom = (slidenum || deck->headers > 1)? 1 : 0;
84 slide_t *slide = deck->slide;
94 while(line && line->text) {
96 if (line->text->value) {
97 lc += url_count_inline(line->text->value);
98 line->length -= url_len_inline(line->text->value);
101 if(line->length > COLS) {
106 i = prev_blank(line->text, offset + COLS) - offset;
108 // single word is > COLS
110 // calculate min_width
111 i = next_blank(line->text, offset + COLS) - offset;
117 fwprintf(stderr, L"Error: Terminal width (%i columns) too small. Need at least %i columns.\n", COLS, i);
118 fwprintf(stderr, L"You may need to shorten some lines by inserting line breaks.\n");
125 max_cols = MAX(i, max_cols);
127 // iterate to next line
128 offset = prev_blank(line->text, offset + COLS);
129 i = line->length - offset;
132 // set max_cols one last time
133 max_cols = MAX(i, max_cols);
136 max_cols = MAX(line->length, max_cols);
142 max_lines = MAX(lc, max_lines);
148 if(max_lines + bar_top + bar_bottom > LINES) {
154 fwprintf(stderr, L"Error: Terminal height (%i lines) too small. Need at least %i lines.\n", LINES, max_lines + bar_top + bar_bottom);
155 fwprintf(stderr, L"You may need to add additional horizontal rules (---) to split your file in shorter slides.\n");
164 // disable output of keyboard typing
167 // make getch() process one char at a time
174 if(has_colors() == TRUE) {
176 use_default_colors();
183 trans = 15; // white in 256 color mode
185 trans = 16; // black in 256 color mode
190 init_pair(CP_WHITE, 232, trans);
191 init_pair(CP_BLUE, 21, trans);
192 init_pair(CP_RED, 196, trans);
193 init_pair(CP_BLACK, 15, 232);
195 init_pair(CP_WHITE, 255, trans);
196 init_pair(CP_BLUE, 123, trans);
197 init_pair(CP_RED, 213, trans);
198 init_pair(CP_BLACK, 16, 255);
200 init_pair(CP_YELLOW, 208, trans);
202 // enable color fading
211 trans = 7; // white in 8 color mode
213 trans = 0; // black in 8 color mode
218 init_pair(CP_WHITE, 0, trans);
219 init_pair(CP_BLACK, 7, 0);
221 init_pair(CP_WHITE, 7, trans);
222 init_pair(CP_BLACK, 0, 7);
224 init_pair(CP_BLUE, 4, trans);
225 init_pair(CP_RED, 1, trans);
226 init_pair(CP_YELLOW, 3, trans);
232 // set background color for main window
234 wbkgd(stdscr, COLOR_PAIR(CP_WHITE));
236 // setup content window
237 WINDOW *content = newwin(LINES - bar_top - bar_bottom, COLS, 0 + bar_top, 0);
239 // set background color of content window
241 wbkgd(content, COLOR_PAIR(CP_WHITE));
245 // find slide to reload
246 while(reload > 1 && reload <= deck->slides) {
252 // reset reload indicator
263 // always resize window in case terminal geometry has changed
264 wresize(content, LINES - bar_top - bar_bottom, COLS);
266 // set main window text color
268 wattron(stdscr, COLOR_PAIR(CP_YELLOW));
273 offset = next_blank(line->text, 0) + 1;
274 // add text to header
276 0, (COLS - line->length + offset) / 2,
277 &line->text->value[offset]);
281 if(deck->headers > 1) {
282 line = deck->header->next;
283 offset = next_blank(line->text, 0) + 1;
285 case 0: // add text to center footer
287 LINES - 1, (COLS - line->length + offset) / 2,
288 &line->text->value[offset]);
291 case 2: // add text to left footer
294 &line->text->value[offset]);
299 // add slide number to right footer
301 case 1: // show slide number only
303 LINES - 1, COLS - int_length(sc) - 3,
306 case 2: // show current slide & number of slides
308 LINES - 1, COLS - int_length(deck->slides) - int_length(sc) - 6,
309 "%d / %d", sc, deck->slides);
313 // copy changed lines in main window to virtual screen
314 wnoutrefresh(stdscr);
321 add_line(content, l, (COLS - max_cols) / 2, line, max_cols, colors);
323 // raise stop counter if we pass a line having a stop bit
324 if(CHECK_BIT(line->bits, IS_STOP))
327 l += (line->length / COLS) + 1;
330 // only stop here if we didn't stop here recently
331 if(stop > slide->stop)
335 // print pandoc URL references
336 // only if we already printed all lines of the current slide
339 getmaxyx( content, ymax, i );
340 for (i = 0; i < url_get_amount(); i++) {
341 mvwprintw(content, ymax - url_get_amount() - 1 + i, 3,
343 waddwstr(content, url_get_target(i));
347 // copy changed lines in content window to virtual screen
348 wnoutrefresh(content);
350 // compare virtual screen to physical screen and does the actual updates
355 fade_in(content, trans, colors, invert);
357 // re-enable fading after any undefined key press
358 if(COLORS == 256 && !nofade)
361 // wait for user input
364 // evaluate user input
368 // show previous slide or stop bit
372 case 8: // BACKSPACE (ascii)
373 case 127: // BACKSPACE (xterm)
374 case 263: // BACKSPACE (getty)
377 if(stop > 1 || (stop == 1 && !line)) {
378 // show current slide again
379 // but stop one stop bit earlier
384 // show previous slide
387 //stop on first bullet point always
397 // show next slide or stop bit
406 // show current slide again
407 // but stop one stop bit later (or at end of slide)
432 i = get_slide_number(c);
433 if(i > 0 && i <= deck->slides) {
450 // disable fading if slide n doesn't exist
465 for(i = sc; i <= deck->slides; i++) {
480 // disable fading if reload is not possible
487 // do not fade out on exit
495 // disable fading on undefined key press
502 fade_out(content, trans, colors, invert);
510 // free ncurses memory
515 // return reload indicator (0 means no reload)
519 void add_line(WINDOW *window, int y, int x, line_t *line, int max_cols, int colors) {
522 int offset = 0; // text offset
524 // move the cursor in position
527 if(!line->text->value) {
529 // fill rest off line with spaces if we are in a code block
530 if(CHECK_BIT(line->bits, IS_CODE) && colors) {
532 wattron(window, COLOR_PAIR(CP_BLACK));
533 for(i = getcurx(window) - x; i < max_cols; i++)
534 wprintw(window, "%s", " ");
541 // IS_UNORDERED_LIST_3
542 if(CHECK_BIT(line->bits, IS_UNORDERED_LIST_3)) {
543 offset = next_nonblank(line->text, 0);
545 strcpy(&prompt[0], CHECK_BIT(line->bits, IS_UNORDERED_LIST_1)? " | " : " ");
546 strcpy(&prompt[4], CHECK_BIT(line->bits, IS_UNORDERED_LIST_2)? " | " : " ");
548 if(CHECK_BIT(line->bits, IS_UNORDERED_LIST_EXT)) {
549 strcpy(&prompt[8], line->next && CHECK_BIT(line->next->bits, IS_UNORDERED_LIST_3)? " | " : " ");
551 strcpy(&prompt[8], " +- ");
558 if(!CHECK_BIT(line->bits, IS_CODE))
559 inline_display(window, &line->text->value[offset], colors);
561 // IS_UNORDERED_LIST_2
562 } else if(CHECK_BIT(line->bits, IS_UNORDERED_LIST_2)) {
563 offset = next_nonblank(line->text, 0);
565 strcpy(&prompt[0], CHECK_BIT(line->bits, IS_UNORDERED_LIST_1)? " | " : " ");
567 if(CHECK_BIT(line->bits, IS_UNORDERED_LIST_EXT)) {
568 strcpy(&prompt[4], line->next && CHECK_BIT(line->next->bits, IS_UNORDERED_LIST_2)? " | " : " ");
570 strcpy(&prompt[4], " +- ");
577 if(!CHECK_BIT(line->bits, IS_CODE))
578 inline_display(window, &line->text->value[offset], colors);
580 // IS_UNORDERED_LIST_1
581 } else if(CHECK_BIT(line->bits, IS_UNORDERED_LIST_1)) {
582 offset = next_nonblank(line->text, 0);
585 if(CHECK_BIT(line->bits, IS_UNORDERED_LIST_EXT)) {
586 strcpy(&prompt[0], line->next && CHECK_BIT(line->next->bits, IS_UNORDERED_LIST_1)? " | " : " ");
588 strcpy(&prompt[0], " +- ");
595 if(!CHECK_BIT(line->bits, IS_CODE))
596 inline_display(window, &line->text->value[offset], colors);
600 if(CHECK_BIT(line->bits, IS_CODE)) {
602 if (!CHECK_BIT(line->bits, IS_TILDE_CODE)) {
603 // set static offset for code
604 offset = CODE_INDENT;
607 // reverse color for code blocks
609 wattron(window, COLOR_PAIR(CP_BLACK));
612 waddwstr(window, &line->text->value[offset]);
615 if(!CHECK_BIT(line->bits, IS_UNORDERED_LIST_1) &&
616 !CHECK_BIT(line->bits, IS_UNORDERED_LIST_2) &&
617 !CHECK_BIT(line->bits, IS_UNORDERED_LIST_3) &&
618 !CHECK_BIT(line->bits, IS_CODE)) {
621 if(CHECK_BIT(line->bits, IS_QUOTE)) {
622 while(line->text->value[offset] == '>') {
623 // print a reverse color block
625 wattron(window, COLOR_PAIR(CP_BLACK));
626 wprintw(window, "%s", " ");
627 wattron(window, COLOR_PAIR(CP_WHITE));
628 wprintw(window, "%s", " ");
630 wprintw(window, "%s", ">");
633 // find next quote or break
635 if(line->text->value[offset] == ' ')
636 offset = next_word(line->text, offset);
639 inline_display(window, &line->text->value[offset], colors);
643 if(CHECK_BIT(line->bits, IS_CENTER)) {
644 if(line->length < max_cols) {
645 wmove(window, y, x + ((max_cols - line->length) / 2));
650 if(CHECK_BIT(line->bits, IS_H1) || CHECK_BIT(line->bits, IS_H2)) {
652 // set headline color
654 wattron(window, COLOR_PAIR(CP_BLUE));
656 // enable underline for H1
657 if(CHECK_BIT(line->bits, IS_H1))
658 wattron(window, A_UNDERLINE);
661 while(line->text->value[offset] == '#')
662 offset = next_word(line->text, offset);
665 waddwstr(window, &line->text->value[offset]);
667 wattroff(window, A_UNDERLINE);
669 // no line-wide markdown
672 inline_display(window, &line->text->value[offset], colors);
677 // fill rest off line with spaces
678 // we only need this if the color is inverted (e.g. code-blocks),
679 // to ensure the background fades too
680 if(CHECK_BIT(line->bits, IS_CODE))
681 for(i = getcurx(window) - x; i < max_cols; i++)
682 wprintw(window, "%s", " ");
684 // reset to default color
686 wattron(window, COLOR_PAIR(CP_WHITE));
687 wattroff(window, A_UNDERLINE);
690 void inline_display(WINDOW *window, const wchar_t *c, const int colors) {
691 const static wchar_t *special = L"\\*_`!["; // list of interpreted chars
692 const wchar_t *i = c; // iterator
693 const wchar_t *start_link_name, *start_url;
694 int length_link_name, url_num;
695 cstack_t *stack = cstack_init();
698 // for each char in line
701 // if char is in special char list
702 if(wcschr(special, *i)) {
704 // closing special char (or second backslash)
705 // only if not followed by :alnum:
706 if((stack->top)(stack, *i) &&
707 (!iswalnum(i[1]) || *(i + 1) == L'\0' || *i == L'\\')) {
710 // print escaped backslash
712 waddnwstr(window, i, 1);
717 wattron(window, COLOR_PAIR(CP_WHITE));
721 wattroff(window, A_UNDERLINE);
723 // disable inline code
726 wattron(window, COLOR_PAIR(CP_WHITE));
730 // remove top special char from stack
733 // treat special as regular char
734 } else if((stack->top)(stack, L'\\')) {
735 waddnwstr(window, i, 1);
737 // remove backslash from stack
740 // opening special char
743 // emphasis or code span can start after new-line or space only
744 // and of cause after another emphasis markup
745 //TODO this condition looks ugly
747 iswspace(*(i - 1)) ||
748 ((iswspace(*(i - 1)) || *(i - 1) == L'*' || *(i - 1) == L'_') &&
749 ((i - 1) == c || iswspace(*(i - 2)))) ||
752 // url in pandoc style
753 if ((*i == L'[' && wcschr(i, L']')) ||
754 (*i == L'!' && *(i + 1) == L'[' && wcschr(i, L']'))) {
758 if (wcschr(i, L']')[1] == L'(' && wcschr(i, L')')) {
761 // turn higlighting and underlining on
763 wattron(window, COLOR_PAIR(CP_BLUE));
764 wattron(window, A_UNDERLINE);
768 // print the content of the label
769 // the label is printed as is
771 waddnwstr(window, i, 1);
773 } while (*i != L']');
775 length_link_name = i - 1 - start_link_name;
782 while (*i != L')') i++;
784 url_num = url_add(start_link_name, length_link_name, start_url, i - start_url, 0, 0);
786 wprintw(window, " [%d]", url_num);
788 // turn highlighting and underlining off
789 wattroff(window, A_UNDERLINE);
790 wattron(window, COLOR_PAIR(CP_WHITE));
793 wprintw(window, "[");
800 wattron(window, COLOR_PAIR(CP_RED));
804 wattron(window, A_UNDERLINE);
806 // enable inline code
809 wattron(window, COLOR_PAIR(CP_BLACK));
811 // do nothing for backslashes
814 // push special char to stack
815 (stack->push)(stack, *i);
818 waddnwstr(window, i, 1);
823 // remove backslash from stack
824 if((stack->top)(stack, L'\\'))
827 // print regular char
828 waddnwstr(window, i, 1);
832 // pop stack until empty to prevent formated trailing spaces
833 while(!(stack->empty)(stack)) {
834 switch((stack->pop)(stack)) {
838 wattron(window, COLOR_PAIR(CP_WHITE));
842 wattroff(window, A_UNDERLINE);
844 // disable inline code
847 wattron(window, COLOR_PAIR(CP_WHITE));
849 // do nothing for backslashes
853 (stack->delete)(stack);
856 void fade_out(WINDOW *window, int trans, int colors, int invert) {
858 if(colors && COLORS == 256) {
859 for(i = 22; i >= 0; i--) {
863 init_pair(CP_WHITE, white_ramp_invert[i], trans);
864 init_pair(CP_BLUE, blue_ramp_invert[i], trans);
865 init_pair(CP_RED, red_ramp_invert[i], trans);
866 init_pair(CP_BLACK, 15, white_ramp_invert[i]);
868 init_pair(CP_WHITE, white_ramp[i], trans);
869 init_pair(CP_BLUE, blue_ramp[i], trans);
870 init_pair(CP_RED, red_ramp[i], trans);
871 init_pair(CP_BLACK, 16, white_ramp[i]);
874 // refresh virtual screen with new color
875 wnoutrefresh(window);
877 // compare virtual screen to physical screen and does the actual updates
880 // delay for our eyes to recognize the change
886 void fade_in(WINDOW *window, int trans, int colors, int invert) {
888 if(colors && COLORS == 256) {
889 for(i = 0; i <= 23; i++) {
891 // brighten color pairs
893 init_pair(CP_WHITE, white_ramp_invert[i], trans);
894 init_pair(CP_BLUE, blue_ramp_invert[i], trans);
895 init_pair(CP_RED, red_ramp_invert[i], trans);
896 init_pair(CP_BLACK, 15, white_ramp_invert[i]);
898 init_pair(CP_WHITE, white_ramp[i], trans);
899 init_pair(CP_BLUE, blue_ramp[i], trans);
900 init_pair(CP_RED, red_ramp[i], trans);
901 init_pair(CP_BLACK, 16, white_ramp[i]);
904 // refresh virtual screen with new color
905 wnoutrefresh(window);
907 // compare virtual screen to physical screen and does the actual updates
910 // delay for our eyes to recognize the change
916 int int_length (int val) {
925 int get_slide_number(char init) {
926 int retval = init - '0';
928 // block for tenths of a second when using getch, ERR if no input
929 halfdelay(GOTO_SLIDE_DELAY);
930 while((c = getch()) != ERR) {
931 if (c < '0' || c > '9') {
935 retval = (retval * 10) + (c - '0');
937 nocbreak(); // cancel half delay mode
938 cbreak(); // go back to cbreak