diff options
Diffstat (limited to 'demo-draw.c')
| -rw-r--r-- | demo-draw.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/demo-draw.c b/demo-draw.c new file mode 100644 index 0000000..85d81fc --- /dev/null +++ b/demo-draw.c @@ -0,0 +1,230 @@ +// <poll.h> might need this for sigset_t +#define _XOPEN_SOURCE 600 + +#include <stdio.h> +#include <unistd.h> +#include <locale.h> +#include <stdarg.h> +#include <stdbool.h> +#include <string.h> + +#include <poll.h> +#include <signal.h> + +#include <curses.h> +#include "termo.h" + +typedef struct app_data app_data_t; +struct app_data +{ + termo_t *tk; + + // Current attributes for the left mouse button + int current_attrs_left; + // Current attributes for the right mouse button + int current_attrs_right; +}; + +static int g_winch_pipe[2]; + +static void +display (const char *format, ...) +{ + va_list ap; + + mvwhline (stdscr, 0, 0, A_REVERSE, COLS); + attron (A_REVERSE); + + va_start (ap, format); + vw_printw (stdscr, format, ap); + va_end (ap); + + attroff (A_REVERSE); + refresh (); +} + +static void +init_palette (app_data_t *app) +{ + start_color (); + + // Also does init_pair (0, -1, -1); + use_default_colors (); + // Duplicate it for convenience. + init_pair (9, -1, -1); + + // Add the basic 8 colors to the default pair. Once normally, once + // inverted to workaround VTE's inability to set a bright background. + for (int i = 0; i < 8; i++) + { + init_pair (1 + i, COLOR_WHITE, COLOR_BLACK + i); + init_pair (10 + i, COLOR_BLACK + i, COLOR_WHITE); + } + + // This usually creates a solid black or white. + app->current_attrs_left = + app->current_attrs_right = COLOR_PAIR (9) | A_REVERSE | A_BOLD; +} + +static void +redraw (void) +{ + int i; + + mvwhline (stdscr, 1, 0, A_REVERSE, COLS); + mvwhline (stdscr, 2, 0, A_REVERSE, COLS); + + for (i = 0; i < COLS; i++) + { + int pair = (float) i / COLS * 9; + mvaddch (1, i, ' ' | COLOR_PAIR (pair)); + mvaddch (2, i, ' ' | COLOR_PAIR (pair + 9) | A_REVERSE | A_BOLD); + } + + display ("Choose a color from the palette and draw. " + "Press Escape or ^C to quit."); + refresh (); +} + +static bool +on_key (app_data_t *app, termo_key_t *key) +{ + if (key->type == TERMO_TYPE_KEYSYM + && key->code.sym == TERMO_SYM_ESCAPE) + return false; + + if (key->type == TERMO_TYPE_KEY + && (key->modifiers & TERMO_KEYMOD_CTRL) + && (key->code.codepoint == 'C' || key->code.codepoint == 'c')) + return false; + + if (key->type != TERMO_TYPE_MOUSE) + return true; + + int line, col, button; + termo_mouse_event_t event; + + termo_interpret_mouse (app->tk, key, &event, &button, &line, &col); + if (event != TERMO_MOUSE_PRESS && event != TERMO_MOUSE_DRAG) + return true; + + int *attrs; + if (button == 1) + attrs = &app->current_attrs_left; + else if (button == 3) + attrs = &app->current_attrs_right; + else + return true; + + chtype ch = mvwinch (stdscr, line, col); + if (line >= 3) + { + // Paste the attributes where the user clicked. + addch (' ' | *attrs); + refresh (); + } + else if (line > 0) + // Copy attributes from the pallete. + *attrs = ch & (A_COLOR | A_ATTRIBUTES); + + return true; +} + +static void +winch_handler (int signum) +{ + (void) signum; + write (g_winch_pipe[1], "x", 1); +} + +int +main (int argc, char *argv[]) +{ + (void) argc; + (void) argv; + + TERMO_CHECK_VERSION; + setlocale (LC_CTYPE, ""); + + struct sigaction act; + act.sa_handler = winch_handler; + act.sa_flags = SA_RESTART; + sigemptyset (&act.sa_mask); + + // Set up a self-pipe so that we can actually poll on SIGWINCH + if (sigaction (SIGWINCH, &act, NULL) || pipe (g_winch_pipe)) + { + fprintf (stderr, "Cannot set up signal handler\n"); + exit (EXIT_FAILURE); + } + + termo_t *tk = termo_new (STDIN_FILENO, NULL, 0); + if (!tk) + { + fprintf (stderr, "Cannot allocate termo instance\n"); + exit (EXIT_FAILURE); + } + + termo_set_mouse_proto (tk, termo_guess_mouse_proto (tk)); + termo_set_mouse_tracking_mode (tk, TERMO_MOUSE_TRACKING_DRAG); + + // Set up curses for our drawing needs + if (!initscr () || nonl () == ERR || curs_set (0) == ERR) + { + fprintf (stderr, "Cannot initialize curses\n"); + exit (EXIT_FAILURE); + } + + app_data_t app; + memset (&app, 0, sizeof app); + app.tk = tk; + + init_palette (&app); + redraw (); + + termo_result_t ret; + termo_key_t key; + + // We listen for mouse/key input and terminal resize events + struct pollfd fds[2] = + { + { .fd = STDIN_FILENO, .events = POLLIN }, + { .fd = g_winch_pipe[0], .events = POLLIN }, + }; + + // Run a simple event loop with poll() + int nextwait = -1; + bool running = true; + while (running) + { + if (!poll (fds, 2, nextwait)) + if (termo_getkey_force (tk, &key) == TERMO_RES_KEY) + running &= on_key (&app, &key); + + if (fds[1].revents & (POLLIN | POLLHUP | POLLERR)) + { + char x; + read (fds[1].fd, &x, 1); + + // The "official" simple and flicker-prone method of resizing + // the internal buffers of curses + endwin (); + refresh (); + + redraw (); + } + if (fds[0].revents & (POLLIN | POLLHUP | POLLERR)) + termo_advisereadable (tk); + + while ((ret = termo_getkey (tk, &key)) == TERMO_RES_KEY) + running &= on_key (&app, &key); + + nextwait = -1; + if (ret == TERMO_RES_AGAIN) + nextwait = termo_get_waittime (tk); + } + + endwin (); + termo_destroy (tk); +} + |