harfbuzz_rs is a high-level interface to HarfBuzz, exposing its most important functionality
in a safe manner using Rust.
HarfBuzz is a library for performing complex text layout. It does not perform any drawing. This is quite a low-level operation. If you want to simply draw some text on the screen choose another library. However if you want to build a library for drawing text on some canvas or need a lot of control on advanced text layout then this is the right library to use.
To shape a simple string of text you just create a Font from a font file, fill a Buffer
with some text and call the shape function.
```rust use harfbuzz_rs::*;
let path = "path/to/some/fontfile.otf"; let index = 0; //< face index in the font file let face = Face::fromfile(path, index)?; let mut font = Font::new(face);
let buffer = UnicodeBuffer::new().add_str("Hello World!"); let output = shape(&font, buffer, &[]);
// The results of the shaping operation are stored in the output buffer.
let positions = output.getglyphpositions(); let infos = output.getglyphinfos();
// iterate over the shaped glyphs for (position, info) in positions.iter().zip(infos) { let gid = info.codepoint; let cluster = info.cluster; let xadvance = position.xadvance; let xoffset = position.xoffset; let yoffset = position.yoffset;
// Here you would usually draw the glyphs.
println!("gid{:?}={:?}@{:?},{:?}+{:?}", gid, cluster, x_advance, x_offset, y_offset);
} ```
This should print out something similar to the following:
text
gid41=0@741,0+0
gid70=1@421,0+0
gid77=2@258,0+0
gid77=3@253,0+0
gid80=4@510,0+0
gid1=5@227,0+0
gid56=6@874,0+0
gid80=7@498,0+0
gid83=8@367,0+0
gid77=9@253,0+0
gid69=10@528,0+0
gid2=11@276,0+0
If you do not want to use rusttype's font functions you can disable the "rusttype" feature.