write_font_fallback.json

The JSON file of the “A Font behind the Font” example. One line of statuses set twice: in a company font alone, where the characters it has no glyph for come out as empty boxes, then with a second font behind it that draws them.

JSON 349 lines

This file is a request: an application sends it over the network to the server, which creates the PDF and sends it back. It creates the same page as the Rust and Python versions of this example. A request names every file it uses, never its content; the call carries the request and the files together. A font the server already holds, such as DejaVuSans, is named with nothing attached. Send the request to the address the API page gives.

This request writes by hand three things the library works out for itself: the number of stretches — seven — the two fonts cut the line into, and the name of each of the two fonts. The count changes whenever the line or either font's coverage changes, and the names change whenever either font file is replaced; since the three values are written by hand in the file, each of those changes means correcting them by hand. Each of the three columns at the foot is given a rectangle wider than the room left beside it, and the third one's runs past the right edge of the page; what they hold fits all the same, because it is short. Two lines of the library's page are not in the request: the house font told to draw nothing for what it lacks, and told to draw a question mark in its place. A request tells only a font it carries itself what to draw for what that font lacks, and the house font is one the server holds, so the request's page has nothing where those two lines stand.

What This Example Is For

A company font rarely has a glyph for every character a document needs. A tick, a star, an umbrella: the font simply does not carry them, and where a glyph is missing the reading software leaves an empty box. The trouble is that the hole passes in silence. The page looks finished, the run goes out, and it is the customer who finds the hole — in the one status line out of forty that happens to use the symbol.

What This Example Shows

Download the File The same example in Rust The same example in Python See What It Creates 
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{
  "fonts": [
    {"name": "plex_box", "part": "IBMPlexSans-Regular.otf", "missing_glyph": "notdef"},
    {"name": "plex_nothing", "part": "IBMPlexSans-Regular.otf", "missing_glyph": "drop"},
    {"name": "plex_question_mark", "part": "IBMPlexSans-Regular.otf", "missing_glyph": {"replace": "?"}}
  ],
  "font_variants": [
    {"name": "plex_standing_in", "from": "plex", "stand_ins": true}
  ],
  "font_chains": [
    {"name": "chained", "faces": ["plex", "DejaVuSans"]},
    {"name": "plex_figures_behind", "faces": ["plex"],
     "ranges": [{"from": "0", "to": "9", "font": "DejaVuSans"}]}
  ],
  "items": [
    {
      "type": "text",
      "rect": {"llx": 60, "lly": 758.4, "urx": 535, "ury": 780},
      "content": ["A font behind the font"],
      "font": "plex",
      "font_size": 18
    },
    {
      "type": "text",
      "rect": {"llx": 60, "lly": 694, "urx": 535, "ury": 750},
      "content": ["A house font rarely covers every character a document has to draw. Without a second font behind it, a character it has no glyph for comes out as the empty box below.\nA chain hands that character to the next font instead, so the line is set in as many fonts as it takes and every mark is drawn."],
      "font": "chained",
      "font_size": 10,
      "leading": 14
    },

    {
      "type": "text",
      "rect": {"llx": 60, "lly": 639.2, "urx": 535, "ury": 650},
      "content": ["The house font alone: what it has no glyph for, it cannot draw."],
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "text",
      "rect": {"llx": 60, "lly": 598, "urx": 535, "ury": 616},
      "content": ["✓ Paid · ★ Priority · ☂ Weather hold · ✗ Refused"],
      "font": "plex",
      "font_size": 15
    },

    {
      "type": "text",
      "rect": {"llx": 60, "lly": 549.2, "urx": 535, "ury": 560},
      "content": ["The house font, with a second one behind it."],
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "text",
      "rect": {"llx": 60, "lly": 508, "urx": 535, "ury": 526},
      "content": ["✓ Paid · ★ Priority · ☂ Weather hold · ✗ Refused"],
      "font": "chained",
      "font_size": 15
    },

    {
      "type": "text",
      "rect": {"llx": 60, "lly": 442, "urx": 535, "ury": 470},
      "content": ["The line above is cut into 7 stretches, drawn by two fonts: IBMPlexSans, then DejaVuSans. The words are in the first; the marks it lacks are in the second."],
      "font": "chained",
      "font_size": 10,
      "leading": 14
    },

    {
      "type": "text",
      "rect": {"llx": 60, "lly": 389.2, "urx": 535, "ury": 400},
      "content": ["Mark"],
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "text",
      "rect": {"llx": 106, "lly": 389.2, "urx": 581, "ury": 400},
      "content": ["Status"],
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "text",
      "rect": {"llx": 236, "lly": 389.2, "urx": 711, "ury": 400},
      "content": ["Drawn by"],
      "font": "plex",
      "font_size": 9
    },

    {
      "type": "text",
      "rect": {"llx": 60, "lly": 358, "urx": 535, "ury": 382},
      "content": ["✓"],
      "font": "chained",
      "font_size": 10
    },
    {
      "type": "text",
      "rect": {"llx": 106, "lly": 358, "urx": 581, "ury": 382},
      "content": ["Paid"],
      "font": "chained",
      "font_size": 10
    },
    {
      "type": "text",
      "rect": {"llx": 236, "lly": 358, "urx": 711, "ury": 382},
      "content": ["IBMPlexSans"],
      "font": "chained",
      "font_size": 10
    },

    {
      "type": "text",
      "rect": {"llx": 60, "lly": 340, "urx": 535, "ury": 364},
      "content": ["★"],
      "font": "chained",
      "font_size": 10
    },
    {
      "type": "text",
      "rect": {"llx": 106, "lly": 340, "urx": 581, "ury": 364},
      "content": ["Priority"],
      "font": "chained",
      "font_size": 10
    },
    {
      "type": "text",
      "rect": {"llx": 236, "lly": 340, "urx": 711, "ury": 364},
      "content": ["DejaVuSans"],
      "font": "chained",
      "font_size": 10
    },

    {
      "type": "text",
      "rect": {"llx": 60, "lly": 322, "urx": 535, "ury": 346},
      "content": ["☂"],
      "font": "chained",
      "font_size": 10
    },
    {
      "type": "text",
      "rect": {"llx": 106, "lly": 322, "urx": 581, "ury": 346},
      "content": ["Weather hold"],
      "font": "chained",
      "font_size": 10
    },
    {
      "type": "text",
      "rect": {"llx": 236, "lly": 322, "urx": 711, "ury": 346},
      "content": ["DejaVuSans"],
      "font": "chained",
      "font_size": 10
    },

    {
      "type": "text",
      "rect": {"llx": 60, "lly": 304, "urx": 535, "ury": 328},
      "content": ["✗"],
      "font": "chained",
      "font_size": 10
    },
    {
      "type": "text",
      "rect": {"llx": 106, "lly": 304, "urx": 581, "ury": 328},
      "content": ["Refused"],
      "font": "chained",
      "font_size": 10
    },
    {
      "type": "text",
      "rect": {"llx": 236, "lly": 304, "urx": 711, "ury": 328},
      "content": ["DejaVuSans"],
      "font": "chained",
      "font_size": 10
    },
    {
      "type": "flow",
      "rect": {
        "llx": 60,
        "lly": 260,
        "urx": 535,
        "ury": 280
      },
      "content": "The house font alone, told three ways what to draw for what it lacks:",
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "flow",
      "rect": {
        "llx": 60,
        "lly": 236,
        "urx": 210,
        "ury": 256
      },
      "content": "the box every font carries",
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "flow",
      "rect": {
        "llx": 220,
        "lly": 236,
        "urx": 535,
        "ury": 256
      },
      "content": "✓ Paid · ★ Priority · ☂ Weather hold · ✗ Refused",
      "font": "plex_box",
      "font_size": 11
    },
    {
      "type": "flow",
      "rect": {
        "llx": 60,
        "lly": 212,
        "urx": 210,
        "ury": 232
      },
      "content": "nothing at all",
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "flow",
      "rect": {
        "llx": 220,
        "lly": 212,
        "urx": 535,
        "ury": 232
      },
      "content": "✓ Paid · ★ Priority · ☂ Weather hold · ✗ Refused",
      "font": "plex_nothing",
      "font_size": 11
    },
    {
      "type": "flow",
      "rect": {
        "llx": 60,
        "lly": 188,
        "urx": 210,
        "ury": 208
      },
      "content": "“?” in its place",
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "flow",
      "rect": {
        "llx": 220,
        "lly": 188,
        "urx": 535,
        "ury": 208
      },
      "content": "✓ Paid · ★ Priority · ☂ Weather hold · ✗ Refused",
      "font": "plex_question_mark",
      "font_size": 11
    },
    {
      "type": "flow",
      "rect": {
        "llx": 60,
        "lly": 160,
        "urx": 210,
        "ury": 184
      },
      "content": "told to draw what it lacks as the character it stands for",
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "flow",
      "rect": {
        "llx": 220,
        "lly": 164,
        "urx": 535,
        "ury": 184
      },
      "content": "273 K",
      "font": "plex_standing_in",
      "font_size": 11
    },
    {
      "type": "flow",
      "rect": {
        "llx": 60,
        "lly": 120,
        "urx": 535,
        "ury": 140
      },
      "content": "The house font's figures, drawn once by the house font and once by the second font:",
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "flow",
      "rect": {
        "llx": 60,
        "lly": 96,
        "urx": 210,
        "ury": 116
      },
      "content": "its own figures",
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "flow",
      "rect": {
        "llx": 220,
        "lly": 96,
        "urx": 535,
        "ury": 116
      },
      "content": "0123456789",
      "font": "plex",
      "font_size": 11
    },
    {
      "type": "flow",
      "rect": {
        "llx": 60,
        "lly": 72,
        "urx": 210,
        "ury": 92
      },
      "content": "the second font's figures",
      "font": "plex",
      "font_size": 9
    },
    {
      "type": "flow",
      "rect": {
        "llx": 220,
        "lly": 72,
        "urx": 535,
        "ury": 92
      },
      "content": "0123456789",
      "font": "plex_figures_behind",
      "font_size": 11
    }
  ]
}