marquee.c

/*
 * compile with DJGPP
 */

#include <stdio.h>
#include <conio.h>
#include <dos.h>
#include <pc.h>

void
rect(int w, int h)
{
  for (int j = 0; j < h; j++) {
    for (int i = 0; i < w; i++) {
      putchar('\xdb');
    }
    putchar('\n');
  }
}

void
draw_bitmap(int bitmap[], int w, int h, int x, int y)
{
  for (int j = 0; j < h; j++) {
    for (int i = 0; i < w; i++) {
      ScreenSetCursor(y + j, 2*(x + i));
      if ((bitmap[j] >> (w - 1 - i)) & 1) printf("\xdb\xdb");
      else                                printf("  ");
    }
  }
}

struct glyph {
  int width;
  int bitmap[5];
} glyphs[127] = {
  ['a'] = {
    3,
    0b010,
    0b101,
    0b111,
    0b101,
    0b101
  },
  ['b'] = {
    3,
    0b110,
    0b101,
    0b110,
    0b101,
    0b110
  },
  ['c'] = {
    3,
    0b111,
    0b101,
    0b100,
    0b101,
    0b111
  },
  ['d'] = {
    3,
    0b110,
    0b101,
    0b101,
    0b101,
    0b110
  },
  ['e'] = {
    3,
    0b111,
    0b100,
    0b111,
    0b100,
    0b111
  },
  ['f'] = {
    3,
    0b111,
    0b100,
    0b111,
    0b100,
    0b100
  },
  ['g'] = {
    3,
    0b111,
    0b101,
    0b111,
    0b001,
    0b111
  },
  ['h'] = {
    3,
    0b101,
    0b101,
    0b111,
    0b101,
    0b101
  },
  ['i'] = {
    3,
    0b111,
    0b010,
    0b010,
    0b010,
    0b111
  },
  ['j'] = {
    4,
    0b1111,
    0b0010,
    0b0010,
    0b1010,
    0b0110
  },
  ['k'] = {
    3,
    0b101,
    0b101,
    0b110,
    0b101,
    0b101
  },
  ['l'] = {
    3,
    0b100,
    0b100,
    0b100,
    0b100,
    0b111
  },
  ['m'] = {
    5,
    0b01010,
    0b10101,
    0b10101,
    0b10101,
    0b10101
  },
  ['n'] = {
    3,
    0b111,
    0b101,
    0b101,
    0b101,
    0b101
  },
  ['o'] = {
    3,
    0b111,
    0b101,
    0b101,
    0b101,
    0b111
  },
  ['p'] = {
    3,
    0b111,
    0b101,
    0b111,
    0b100,
    0b100
  },
  ['q'] = {
    3,
    0b111,
    0b101,
    0b111,
    0b010,
    0b001
  },
  ['r'] = {
    3,
    0b111,
    0b101,
    0b110,
    0b101,
    0b101
  },
  ['s'] = {
    3,
    0b111,
    0b100,
    0b111,
    0b001,
    0b111
  },
  ['t'] = {
    3,
    0b111,
    0b010,
    0b010,
    0b010,
    0b010
  },
  ['u'] = {
    3,
    0b101,
    0b101,
    0b101,
    0b101,
    0b111
  },
  ['v'] = {
    3,
    0b101,
    0b101,
    0b101,
    0b101,
    0b010
  },
  ['w'] = {
    5,
    0b10101,
    0b10101,
    0b10101,
    0b10101,
    0b01010
  },
  ['x'] = {
    3,
    0b101,
    0b101,
    0b010,
    0b101,
    0b101
  },
  ['y'] = {
    3,
    0b101,
    0b101,
    0b010,
    0b010,
    0b010
  },
  ['z'] = {
    3,
    0b111,
    0b001,
    0b010,
    0b100,
    0b111
  },
  ['0'] = {
    3,
    0b010,
    0b101,
    0b101,
    0b101,
    0b010
  },
  ['1'] = {
    3,
    0b010,
    0b110,
    0b010,
    0b010,
    0b111
  },
  ['2'] = {
    3,
    0b010,
    0b101,
    0b001,
    0b010,
    0b111
  },
  ['3'] = {
    3,
    0b110,
    0b001,
    0b111,
    0b001,
    0b110
  },
  ['4'] = {
    3,
    0b101,
    0b101,
    0b111,
    0b001,
    0b001
  },
  ['5'] = {
    3,
    0b111,
    0b100,
    0b111,
    0b001,
    0b110
  },
  ['6'] = {
    3,
    0b011,
    0b100,
    0b111,
    0b101,
    0b010
  },
  ['7'] = {
    3,
    0b111,
    0b001,
    0b001,
    0b010,
    0b100
  },
  ['8'] = {
    3,
    0b111,
    0b101,
    0b111,
    0b101,
    0b111
  },
  ['9'] = {
    3,
    0b111,
    0b101,
    0b111,
    0b001,
    0b110
  }
};

void
draw_string(char *s)
{
  int w = 0;
  for (int i = 0; s[i] != 0; i++) {
    if (s[i] == ' ') {
      w += 2;
    } else {
      struct glyph *g = &glyphs[s[i]];
      draw_bitmap(g->bitmap, g->width, 5, w, 0);
      w += g->width + 1;
    }
  }
}

void
draw_bitmap_column(int bitmap[], int w, int i, int x)
{
  for (int y = 0; y < 5; y++) {
    ScreenSetCursor(y, 2*(x + i));
    if ((bitmap[y] >> (w - 1 - i)) & 1) printf("\xdb\xdb");
    else                                printf("  ");
  }
}

void
marquee(char *s, int window, int shift)
{
  int w = 0;
  for (int i = 0; s[i] != 0; i++) {
    if (s[i] == ' ') {
      w += 2;
    } else {
      struct glyph *g = &glyphs[s[i]];
      for (int j = 0; j < g->width; j++) {
        if (w + j - shift >= window)
          return;
        if (w + j >= shift)
          draw_bitmap_column(g->bitmap, g->width, j, w - shift);
      }
      w += g->width + 1;
    }
  }
}

int
main(int argc, char *argv)
{
  int n = -39;
  for (;;) {
    clrscr();
    marquee("abcdefghijklmnopqrstuvwxyz 0123456789", 40, n++);
    delay(50);
    if (n >= 150) n = -39;
    if (kbhit()) break;
    /*
    int c = getch();
    if (c == ' ') break;
    struct glyph *g = &glyphs[c];
    clrscr();
    draw_bitmap(g->bitmap, g->width, 5, 0, 0);
    */
  }
  return 0;
}