如何通过read-fonts循环遍历字体表的字段

Question

我想遍历给定字体的所有字体表并打印/获取表内容属性和值，但我不知道该怎么做。

[dependencies]
write-fonts = { version = "*", features = ["read"] }

use write_fonts::read::FontRef;


fn main() {
    let path_to_my_font_file = std::path::Path::new("/Users/ollimeier/Documents/Vary-Black.otf");

    let font_bytes = std::fs::read(path_to_my_font_file).unwrap();
    let font = FontRef::new(&font_bytes).expect("failed to read font data");

    for table in font.table_directory.table_records() {
        let tag = table.tag();

        println!("    table {tag} ...");
        println!("    {tag}: {:?}", table);

        //for table_field in table {
        //    println!("    table field {table_field} ...");
        //}
    }
}

Answer 1

要从

table_directory

遍历表格，您必须调用方法

traverse

来获取

RecordResolver

，然后实现

SomeTable

为您提供一个可以迭代的

iter

：

use write_fonts::read::traversal::{SomeRecord, SomeTable};
use write_fonts::read::FontRef;

fn main() {
    let font_bytes =
        include_bytes!("/usr/share/fonts/adobe-source-code-pro/SourceCodePro-Black.otf");
    let font = FontRef::new(font_bytes).expect("failed to read font data");

    for table in font.table_directory.table_records() {
        let tag = table.tag();

        println!("    table {tag} ...");
        println!("    {tag}: {:?}", table);

        let table = table.clone().traverse(font.table_data(tag).unwrap());
        for table_field in (&table as &dyn SomeTable).iter() {
            println!("{}: {:?}", table_field.name, table_field.value);
        }
    }
}

库 API 确实很重要......