Example: midi_2

Console

import "allegro-ts/global";
import { screen } from "allegro-ts";

async function main(argc = 2, argv = ["", "assets/hotel.mid"]): Promise<number> {
  let the_music: MIDI | null = null;
  let length = 0,
    pos = 0;
  let beats = 0,
    beat = 0;
  let x = 0,
    y = 0,
    tw = 0,
    th = 0;
  let background_color = 0;
  let text_color = 0;
  let paused = false;
  let done = 0;

  if (allegro_init() != 0) return 1;

  if (argc != 2) {
    allegro_message("Usage: 'exmidi filename.mid'\n");
    return 1;
  }

  install_keyboard();
  install_timer();

  /* install a MIDI sound driver */
  if (install_sound(DIGI_AUTODETECT, MIDI_AUTODETECT, null) != 0) {
    allegro_message("Error initialising sound system\n%s\n", allegro_error);
    return 1;
  }

  /* read in the MIDI file */
  the_music = await load_midi(argv[1] ?? "");

  if (!the_music) {
    allegro_message("Error reading MIDI file '%s'\n", argv[1] ?? "");
    return 1;
  }

  length = get_midi_length(the_music);
  beats = -midi_pos.value; /* get_midi_length updates midi_pos to the negative
                         number of beats (quarter notes) in the midi. */

  if (set_gfx_mode(GFX_AUTODETECT, 320, 200, 0, 0) != 0) {
    if (set_gfx_mode(GFX_SAFE, 320, 200, 0, 0) != 0) {
      set_gfx_mode(GFX_TEXT, 0, 0, 0, 0);
      allegro_message("Unable to set any graphic mode\n%s\n", allegro_error);
      return 1;
    }
  }

  /* try to continue in the background */
  if (set_display_switch_mode(SWITCH_BACKGROUND)) set_display_switch_mode(SWITCH_BACKAMNESIA);

  set_palette(desktop_palette);
  background_color = makecol(255, 255, 255);
  text_color = makecol(0, 0, 0);
  clear_to_color(screen.value, background_color);
  th = text_height(font);
  x = SCREEN_W.value / 2;

  textprintf_centre_ex(screen.value, font, x, SCREEN_H.value / 3, text_color, -1, "Driver: %s", midi_driver.name);
  textprintf_centre_ex(screen.value, font, x, SCREEN_H.value / 2, text_color, -1, "Playing %s", argv[1] ?? "");

  /* start up the MIDI file */
  play_midi(the_music, true);

  y = (2 * SCREEN_H.value) / 3;
  tw = text_length(font, "0000:00 / 0000:00");
  /* wait for a key press */
  while (!done) {
    /* P key pauses/resumes, any other key exits. */
    while (keypressed()) {
      const k = (await readkey()) & 255;
      if (k == KEY_P) {
        paused = !paused;
        if (paused) {
          midi_pause();
          textprintf_centre_ex(screen.value, font, x, y + th * 3, text_color, -1, "P A U S E D");
        } else {
          midi_resume();
          rectfill(screen.value, x - tw / 2, y + th * 3, x + tw / 2, y + th * 4, background_color);
        }
      } else done = 1;
    }
    pos = midi_time.value;
    beat = midi_pos.value;
    rectfill(screen.value, x - tw / 2, y, x + tw / 2, y + th * 2, background_color);
    textprintf_centre_ex(
      screen.value,
      font,
      x,
      y,
      text_color,
      -1,
      "%d:%02d / %d:%02d",
      pos / 60,
      pos % 60,
      length / 60,
      length % 60,
    );
    textprintf_centre_ex(screen.value, font, x, y + th, text_color, -1, "beat %d / %d", beat, beats);
    /* We have nothing else to do. */
    await rest(100);
  }

  /* destroy the MIDI file */
  destroy_midi(the_music);

  return 0;
}

END_OF_MAIN();

// Start
export const run = () => {
  init_allegro_ts("canvas_id", main, {
    debug_element: "debug",
  });
};

View source on GitHub