From 49c6a31742e54fa5d6bfa31d6baa8a88ad78d315 Mon Sep 17 00:00:00 2001 From: Přemysl Janouch Date: Mon, 3 Oct 2016 06:01:28 +0200 Subject: Add a scrollbar --- nncmpp.c | 125 +++++++++++++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 101 insertions(+), 24 deletions(-) diff --git a/nncmpp.c b/nncmpp.c index 69b7a15..d58cc26 100644 --- a/nncmpp.c +++ b/nncmpp.c @@ -113,7 +113,8 @@ update_curses_terminal_size (void) \ XX( EVEN, "even", -1, -1, 0 ) \ XX( ODD, "odd", -1, -1, 0 ) \ - XX( SELECTION, "selection", -1, -1, A_REVERSE ) + XX( SELECTION, "selection", -1, -1, A_REVERSE ) \ + XX( SCROLLBAR, "scrollbar", -1, -1, 0 ) enum { @@ -150,6 +151,7 @@ struct row_buffer; typedef bool (*tab_event_fn) (struct tab *self, termo_key_t *event); /// Draw an item to the screen using the row buffer API +// TODO: this will probably want to know the actual width typedef void (*tab_item_draw_fn) (struct tab *self, unsigned item_index, struct row_buffer *buffer); @@ -230,6 +232,7 @@ static struct app_context termo_t *tk; ///< termo handle struct poller_timer tk_timer; ///< termo timeout timer bool locale_is_utf8; ///< The locale is Unicode + bool use_partial_boxes; ///< Use Unicode box drawing chars struct attrs attrs[ATTRIBUTE_COUNT]; } @@ -411,6 +414,10 @@ app_init_context (void) // Note that non-Unicode locales are handled pretty inefficiently. g_ctx.locale_is_utf8 = !strcasecmp_ascii (locale_charset (), "UTF-8"); + // It doesn't work 100% (e.g. incompatible with undelining in urxvt) + // TODO: make this configurable + g_ctx.use_partial_boxes = g_ctx.locale_is_utf8; + app_init_attributes (); } @@ -762,18 +769,15 @@ app_write_gauge (struct row_buffer *buf, float ratio, int width) // because sometimes Unicode is even useful int len_left = ratio * width * 8 + 0.5; - static const char *partials[] = { " ", "▏", "▎", "▍", "▌", "▋", "▊", "▉"}; - int remainder = len_left % N_ELEMENTS (partials); - len_left /= N_ELEMENTS (partials); + static const char *partials[] = { " ", "▏", "▎", "▍", "▌", "▋", "▊", "▉" }; + int remainder = len_left % 8; + len_left /= 8; - // Assuming that if we can show the 1/8 box then we can show them all const char *partial = NULL; - // TODO: cache this setting and make it configurable since it doesn't seem - // to work 100% (e.g. incompatible with undelining in urxvt) - if (!app_is_character_in_locale (L'▏')) - len_left += remainder >= (int) N_ELEMENTS (partials) / 2; - else + if (g_ctx.use_partial_boxes) partial = partials[remainder]; + else + len_left += remainder >= (int) 4; int len_right = width - len_left; while (len_left-- > 0) @@ -902,39 +906,119 @@ app_redraw_top (void) refresh (); } +static int +app_visible_items (void) +{ + // This may eventually include a header bar and/or a status bar + return MAX (0, LINES - g_ctx.top_height); +} + +static void +app_redraw_scrollbar (void) +{ + // This assumes that we can write to the one-before-last column, + // i.e. that it's not covered by any double-wide character (and that + // ncurses comes to the right results when counting characters). + // + // We could also precompute the scrollbar and append it to each row + // as we render them, plus all the unoccupied rows. + struct tab *tab = g_ctx.active_tab; + int visible_items = app_visible_items (); + + if (!g_ctx.use_partial_boxes) + { + // Apparently here we don't want the 0.5 rounding constant + int length = (float) visible_items / (int) tab->item_count + * (visible_items - 1); + int start = (float) tab->item_top / (int) tab->item_count + * (visible_items - 1); + + for (int row = 0; row < visible_items; row++) + { + move (g_ctx.top_height + row, COLS - 1); + if (row < start || row > start + length + 1) + addch (' ' | APP_ATTR (SCROLLBAR)); + else + addch (' ' | APP_ATTR (SCROLLBAR) | A_REVERSE); + } + return; + } + + // TODO: clamp the values, make sure they follow the right order + // We subtract half a character from both the top and the bottom, hence -1 + int length = (float) visible_items / (int) tab->item_count + * (visible_items - 1) * 8 + 0.5; + int start = (float) tab->item_top / (int) tab->item_count + * (visible_items - 1) * 8 + 0.5; + + // Then we make sure the bar is high at least one character, hence +8 + int end = start + length + 8; + + int start_part = start % 8; start /= 8; + int end_part = end % 8; end /= 8; + + // Even with this, the solid part must be at least one character high + static const char *partials[] = { "█", "▇", "▆", "▅", "▄", "▃", "▂", "▁" }; + + for (int row = 0; row < visible_items; row++) + { + chtype attrs = APP_ATTR (SCROLLBAR); + if (row > start && row <= end) + attrs ^= A_REVERSE; + + const char *c = " "; + if (row == start) c = partials[start_part]; + if (row == end) c = partials[end_part]; + + move (g_ctx.top_height + row, COLS - 1); + + struct row_buffer buf; + row_buffer_init (&buf); + row_buffer_append (&buf, c, attrs); + row_buffer_flush (&buf); + row_buffer_free (&buf); + } +} + static void app_redraw_view (void) { move (g_ctx.top_height, 0); clrtobot (); - // TODO: display a scrollbar on the right side struct tab *tab = g_ctx.active_tab; + bool want_scrollbar = (int) tab->item_count > app_visible_items (); + int view_width = COLS - want_scrollbar; + int to_show = MIN (LINES - g_ctx.top_height, (int) tab->item_count - tab->item_top); - for (int row_index = 0; row_index < to_show; row_index++) + for (int row = 0; row < to_show; row++) { - int item_index = tab->item_top + row_index; + int item_index = tab->item_top + row; int row_attrs = (item_index & 1) ? APP_ATTR (ODD) : APP_ATTR (EVEN); if (item_index == tab->item_selected) row_attrs = APP_ATTR (SELECTION); attrset (row_attrs); + move (g_ctx.top_height + row, 0); struct row_buffer buf; row_buffer_init (&buf); tab->on_item_draw (tab, item_index, &buf); - if (buf.total_width > COLS) - row_buffer_ellipsis (&buf, COLS, row_attrs); + if (buf.total_width > view_width) + row_buffer_ellipsis (&buf, view_width, row_attrs); row_buffer_flush (&buf); - for (int i = buf.total_width; i < COLS; i++) + for (int i = buf.total_width; i < view_width; i++) addch (' '); row_buffer_free (&buf); } - attrset (0); + + if (want_scrollbar) + app_redraw_scrollbar (); + refresh (); } @@ -947,13 +1031,6 @@ app_redraw (void) // --- Actions ----------------------------------------------------------------- -static int -app_visible_items (void) -{ - // This may eventually include a header bar and/or a status bar - return MAX (0, LINES - g_ctx.top_height); -} - /// Checks what items that are visible and returns if fixes were needed static bool app_fix_view_range (void) -- cgit v1.2.3-70-g09d2