https://github.com/sternenseemann/buchstabensuppe

toy font rendering for low pixelcount, high contrast displays
https://github.com/sternenseemann/buchstabensuppe

bitmap c flipdot flipdots font font-rendering text-shaping

Last synced: 27 days ago
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toy font rendering for low pixelcount, high contrast displays

• Host: GitHub
• URL: https://github.com/sternenseemann/buchstabensuppe
• Owner: sternenseemann
• License: bsd-3-clause
• Created: 2020-12-11T14:08:45.000Z (almost 4 years ago)
• Default Branch: main
• Last Pushed: 2022-05-03T09:38:11.000Z (over 2 years ago)
• Last Synced: 2023-08-05T11:12:45.866Z (over 1 year ago)
• Topics: bitmap, c, flipdot, flipdots, font, font-rendering, text-shaping
• Language: C
• Homepage: https://sternenseemann.github.io/buchstabensuppe
• Size: 172 KB
• Stars: 7
• Watchers: 3
• Forks: 2
• Open Issues: 1
• Metadata Files:
  • Readme: README.md
  • License: COPYING

Awesome Lists containing this project

README

        
# buchstabensuppe

```

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 █    █  █     

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 █    █     ██ 

 █    █       █

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 █ ███    ████ 

```

> at least better than PIL.ImageFont

toy font rendering for low pixelcount high contrast displays,

i. e. [openlab's flipdot display](https://wiki.openlab-augsburg.de/Flipdots).

## features

* supports [text shaping](https://harfbuzz.github.io/what-is-harfbuzz.html#what-is-text-shaping)

  via harfbuzz

* per grapheme cluster font fallback

* grayscale and binary b/w support

## building

requirements:

* [redo-c](https://github.com/leahneukirchen/redo-c)

* Optionally `make` for install script and such

* [utf8proc](https://juliastrings.github.io/utf8proc)

* [harfbuzz](harfbuzz.github.io/)

* [libschrift](https://github.com/tomolt/libschrift) == 0.10.1

```

# run inside nix-shell if you have nix!

# static library

$ redo libbuchstabensuppe.a

# demo binary

$ redo bs-renderflipdot.exe

# tests

$ redo test.exe && ./test.exe

```

alternatively you can just run `nix-build`

## demo

if you want to play around with the font rendering in binary

mode you can use the dry run mode of the supplied `./bs-renderflipdot.exe`

(or `./result/bin/bs-renderflipdot` if you use nix) binary.

Run `./bs-renderflipdot.exe -?` for usage instructions and don't forget `-n`

for dry running!

```

$ ./bs-renderflipdot.exe -f fonts/unifont.ttf -f fonts/unifont_upper.ttf -n "Greetings ❣️" 2>/dev/null

                                                                                            

                                                                                    ███ ███ 

                                                                                   █████████

                                            █                                      █████████

  ████                             █        █                                      █████████

 █    █                            █                          █                     ███████ 

 █    █  █ ███    ████    ████     █       ██    █ ███    ███ █   ████                ███   

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 █  ███  █       ██████  ██████    █        █    █    █  █   █    ██                  ███   

 █    █  █       █       █         █        █    █    █   ███       ██               █████  

 █    █  █       █       █         █        █    █    █   █           █              █████  

 █   ██  █       █    █  █    █    █        █    █    █   ████   █    █              █████  

  ███ █  █        ████    ████      ██    █████  █    █  █    █   ████                ███   

                                                         █    █                             

                                                          ████                              

```

## flipdot interaction

![An example where buchstabensuppe does an admirable job rendering a string onto a simulated flipdot display](doc/flipdot-render.png)

the picture above shows buchstabensuppe being used to render text

onto a simulated flipdot display. take notice especially of the following:

* fallback fonts are supported: the emoji is not found in `unifont.ttf`,

  but rendered from `unifont_upper.ttf`

* correct text shaping is supported (as far as the font supports it):

  g̈ which consists of two codepoints is rendered as a combined cluster

  consisting of two glyphs.

[bs-renderflipdot.c](./bs-renderflipdot.c) is a simple example showing

how to interact with a flipdot display. mainly it involves:

* rendering a string to a bitmap using `bs_render_utf8_string`

* making sure that the dimensions of the display and the image

  match with `bs_bitmap_extend`

* processing the resulting bitmap using `bs_bitmap_map`

* rendering the resulting bitmap on the display using

  `bs_flipdot_render`.

* dealing with bitmaps too big for the display using

  `bs_scroll_next_view` and `bs_page_next_view`.

you can also play around with its cli: the following command

renders “Hello World” black on white using GNU Unifont onto

a flipdot display (or simulator) running on `localhost:2323`.

See [bs-renderflipdot(1)](https://sternenseemann.github.io/buchstabensuppe/bs-renderflipdot.1.html)

for more usage details.

```

./bs-renderflipdot.exe -f /path/to/unifont.ttf -f /path/to/unifont_upper.ttf -i "Hello World"

```

## caveats

* buchstabensuppe loads all fonts into memory and keeps them there pretty much

  all the time.

* there is no support for right to left nor vertical script (but planned)