https://github.com/pushfoo/fontknife
Rasterize only the glyphs you need. Cut out everything else.
https://github.com/pushfoo/fontknife
Last synced: 10 months ago
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Rasterize only the glyphs you need. Cut out everything else.
- Host: GitHub
- URL: https://github.com/pushfoo/fontknife
- Owner: pushfoo
- License: mit
- Created: 2022-08-23T02:12:18.000Z (over 3 years ago)
- Default Branch: main
- Last Pushed: 2025-02-23T04:45:16.000Z (12 months ago)
- Last Synced: 2025-04-14T01:53:12.366Z (10 months ago)
- Language: Python
- Homepage:
- Size: 420 KB
- Stars: 5
- Watchers: 2
- Forks: 0
- Open Issues: 6
-
Metadata Files:
- Readme: README.md
- Contributing: CONTRIBUTING.md
- License: LICENSE
Awesome Lists containing this project
README
# Fontknife
[](https://opensource.org/licenses/BSD-3-Clause)
[](https://makeapullrequest.com)
[](https://github.com/pushfoo/Fontknife/actions/workflows/test.yaml?branch=main)
[](https://fontknife.readthedocs.io/en/main/?badge=main)
[](https://fontknife.readthedocs.io/en/stable/?badge=stable)
**Q**: How do I convert a font into a sprite sheet?
**A**: `fontknife convert`
| Goal | End Result | Command |
|---------------------------------|:----------------------------------------------------------------------------:|------------------------------------------------------------------------|
| Rasterize a font's ASCII glyphs |  | `fontknife convert supported.font spritesheet.png` |
| Generate filler assets |  | `fontknife convert -P 48 -G "💪😎" NotoEmoji-Regular.ttf arm_cool.png` |
For more detailed explanations, see [Practical Examples](#practical-examples).
## Install Instructions
### Users
If you only want to convert fonts, follow these steps:
1. Have [Python](https://python.org) 3.9+ installed
2. Make sure you've [created](https://docs.python.org/3/library/venv.html#creating-virtual-enviroments)
and [activated](https://docs.python.org/3/library/venv.html#how-venvs-work)
a virtual environment (or use [pipx](https://pypa.github.io/pipx/))
3. `pip install`
4. Run `fontknife convert --help`
If the last command prints help text, you're ready to go! Read it for more information about supported features.
### Developers / Contributors
See [CONTRIBUTING.md](https://github.com/pushfoo/fontknife/blob/master/CONTRIBUTING.md).
## Current Features
* Read multiple font formats (TTF, BDF, PCF, 1-bit sprite sheets)
* Read arbitrary unicode glyphs from supported fonts, including
[multi-character emoji](https://unicode.org/emoji/charts/emoji-zwj-sequences.html)
* Export 1-bit sprite sheets to multiple image formats (PNG, BMP, JPG)
* Guess common formats from file extensions
* Simpler than GUI font editors
* Can be used as a library in custom Python scripts
* Assembly code generation (Partial support for [Octo](https://github.com/JohnEarnest/Octo))
Please remember:
1. This is alpha quality software, so there will be bugs and breaking changes
2. The [Future Features](#future-features) section lists known areas for improvements
3. The project accepts [pull requests](https://github.com/pushfoo/fontknife/pulls)
## Why did you make this?
1. It helps developers [iterate faster](https://www.youtube.com/watch?v=rDjrOaoHz9s).
2. A refactor of an abandoned projected turned into something else.
## Practical Examples
### 1. Export Specific Glyphs / Make Game Assets
**Scenario**: You need filler assets for a farming game, ASAP.
**Solution**:
1. Download an appropriately licensed emoji font, such as
[Noto Emoji](https://fonts.google.com/noto/specimen/Noto+Emoji),
2. Run the following command
```commandline
fontknife convert -P 48 -G "🌽🍇🍎🍏🫐🍓🍒🍐🍅🥕🥔🥒🍑🥑🧅🍈" NotoEmoji-Regular.ttf fruits_and_veggies.png
```
3. Double check & color the results with your preferred image editor
### 3. Generate Octo Assembly
_Note: This feature is mostly broken legacy code inherited from
an earlier project._
You can generate a width table and sprite data table as valid
[Octo](https://github.com/JohnEarnest/Octo) source if your font meets
the following requirements:
1. All glyphs can render as 8px x 8px or smaller
2. There are 256 or fewer glyphs in the font
For example, run the following to generate tables of widths and sprite data
for [Tom Thumb](https://robey.lag.net/2010/01/23/tiny-monospace-font.html)
as Octo source:
```commandline
fontknife emit-code tom-thumb.bdf tom-thumb.8o
```
The data tables should be usable, but the attached drawing routines are not:
1. Their underlying logic is broken
2. They predate Octo's idiomatic [`:stringmode` macro](http://johnearnest.github.io/Octo/docs/Manual.html#strings)
## Future features
Features in this section will be added if:
1. A PR is made addressing it
2. I have time / interest
The features below are in descending order, from highest to lowest priority:
| Feature | Questions / Blockers | Easiest known approach |
|----------------------------------------------------------------|--------------------------------------|-------------------------------------------------------------------------------|
| Better documentation | | Sphinx + RTD, in progress |
| Fix automatic sheet sizing | | |
| Export with transparent background color | Outline detection | Improve cli color parsing, replace `#000` default with `#0000` |
| Add foreground color control | | Same as above |
| Export to folder of files per glyph | File naming | Use the unicode [code point](https://en.wikipedia.org/wiki/Code_point) |
| Support for automatically reading TTF glyph tables | | Use [fonttools](https://github.com/fonttools/fonttools) to read the TTF table |
| Fix ugly caching behavior | | Delete / disable caching entirely |
| Better scaling flags, including downsampling | | Recommend imagemagick or image editors |
| Additional font formats (see [Future Formats](#future-formats) | | Time / interest |
| C header code generation | | Time / interest |
| Refactor or remove Octo generation | | Move it to a downstream project |
| Better interface for glyph subset selection | Good design unclear | Write doc on using fontknife in scripts |
| Color TTF support | Pillow has bad support for color TTF | Unknown, help welcome! |
### Future Formats
Potential font formats to support:
* [FNT](https://web.archive.org/web/20110513200924/http://support.microsoft.com/kb/65123) and other old Windows formats
* [UXF](https://wiki.xxiivv.com/site/ufx_format.html)