The generated pdf contains just two characters up to 56.5MB

[eksea]

i create a pdf file with just two Chinese characters. But the file size is 56MB. The font i use is 'STHeiti Medium.ttc' on mac which size is 53MB.

[fschutt]

Yeah, it embeds the entire font without subsetting.

This could technically be solved with switching to subsetting fonts with allsorts and only using the glyphs that are being used.

[eksea]

Yes，i solved the problem with the help of allsorts finally.

[dnlmlr]

I implemented basic font subsetting which was merged in e412845dd5ca798a0e630ce3320ed2a5e6c1df0b . Since you also seem to have used allsorts, I would be curious if you have any comments / improvement ideas. Or even if you did it in a totally different way.

[eksea]

There's a font.rs in example. It read a font from file and then use it write text. I just use allsorts to generate a small font in memory, and then use the same api get a same font object, just like the example。

let small_font = subset_text(&provider, &all_text).unwrap();
let mut font_reader = std::io::Cursor::new(small_font);
let font = doc.add_external_font(&mut font_reader).unwrap();