tomevault-io fontbm — Bitmap Font Generator
fontbm is a command-line utility that converts TTF/OTF fonts into bitmap font atlases compatible with the AngelCode BMFont format.
Basic Usage
fontbm --font-file FreeSans.ttf --output myfont
Produces two files:
myfont.fnt— metadata (character positions, kerning, etc.)myfont_0.png— texture atlas image
Required Options
| Option | Description |
|---|---|
--font-file <path> |
Path to the TTF/OTF font file |
--output <name> |
Output filename without extension |
Optional Parameters
| Option | Default | Description |
|---|---|---|
--font-size <n> |
32 | Font size in pixels |
--chars <range> |
32-126 | Character range(s), e.g. 32-126 or 32-64,92,120-126 |
--chars-file <path> |
— | UTF-8 text file with additional characters to include |
--color <r,g,b> |
255,255,255 | Foreground RGB color |
--background-color <r,g,b> |
transparent | Background RGB color |
--monochrome |
off | Disable anti-aliasing (1-bit rendering) |
--data-format <fmt> |
txt | Output format: txt, xml, bin, json |
--kerning-pairs <mode> |
disabled | Kerning: disabled, basic, regular, extended |
--texture-size <w,h> |
auto | Allowed texture dimensions (comma-separated list of sizes) |
--texture-crop-width |
off | Crop unused horizontal space from the texture |
--texture-crop-height |
off | Crop unused vertical space from the texture |
--max-texture-count <n> |
unlimited | Maximum number of texture pages |
--texture-name-suffix <s> |
index_aligned | Suffix style: index_aligned, index, none |
--padding-up <n> |
0 | Top padding per glyph (pixels) |
--padding-right <n> |
0 | Right padding per glyph (pixels) |
--padding-down <n> |
0 | Bottom padding per glyph (pixels) |
--padding-left <n> |
0 | Left padding per glyph (pixels) |
--spacing-vert <n> |
0 | Vertical spacing between glyphs |
--spacing-horiz <n> |
0 | Horizontal spacing between glyphs |
Examples
Generate a 48px font with Latin characters:
fontbm --font-file Arial.ttf --output arial48 --font-size 48
Generate with a custom character range and JSON output:
fontbm --font-file FreeSans.ttf --output ui_font --font-size 24 --chars 32-126 --data-format json
Generate a monochrome font with padding for SDF-like workflows:
fontbm --font-file FreeSans.ttf --output mono_font --monochrome --padding-up 4 --padding-right 4 --padding-down 4 --padding-left 4
Generate a colored font on a dark background:
fontbm --font-file FreeSans.ttf --output colored --color 255,200,0 --background-color 0,0,0
Include characters from a file (useful for Unicode/CJK):
fontbm --font-file NotoSans.ttf --output cjk_font --chars-file my_chars.txt
Output Format Notes
- txt (default): AngelCode BMFont text format — widely supported
- xml: AngelCode BMFont XML format
- bin: AngelCode BMFont binary format
- json: JSON format
Running fontbm
The binary should be in the project directory or on PATH:
./fontbm --font-file FreeSans.ttf --output myfont
On Windows:
fontbm.exe --font-file FreeSans.ttf --output myfont
Source: vladimirgamalyan/fontbm — distributed by TomeVault.