font subsetting: pyftsubset -> allsorts

build.rs

@@ -1,8 +1,14 @@
-use epaint::{
-    FontFamily,
-    text::{FontData, FontDefinitions, FontTweak},
+use allsorts::{
+    binary::read::ReadScope,
+    font::{Font, MatchingPresentation},
+    font_data::FontData as AllsortsFontData,
+    subset::subset,
+    tag,
+};
+use epaint::{
+    text::{FontData, FontDefinitions, FontTweak},
+    FontFamily,
 };
-use run_script::ScriptOptions;
 use std::{
     collections::BTreeMap,
     env,
@@ -18,52 +24,44 @@ include!(concat!(
 ));
 
 fn font_stripper(from: &str, out: &str, unicodes: Vec<char>) -> Result<Vec<u8>, String> {
-    let unicodes: Vec<String> = unicodes.iter().map(|c| to_unicode_hash(*c)).collect();
+    let font_path = format!("{}/assets/{}", env!("CARGO_MANIFEST_DIR"), from);
+    let font_data = std::fs::read(&font_path).map_err(|e| e.to_string())?;
+    let scope = ReadScope::new(&font_data);
+    let font_file = scope
+        .read::<AllsortsFontData>()
+        .map_err(|e| format!("Failed to read font data: {}", e))?;
+    let provider = font_file
+        .table_provider(0)
+        .map_err(|e| format!("Failed to get table provider: {}", e))?;
+    let mut font = Font::new(provider).map_err(|e| format!("Failed to create font: {:?}", e))?;
+
+    let mut glyph_ids = Vec::new();
+    for &ch in &unicodes {
+        let mut glyph_ids_curr = font
+            .map_glyphs(
+                &ch.to_string(),
+                tag::LATN,
+                MatchingPresentation::NotRequired,
+            )
+            .into_iter()
+            .map(|glyph| glyph.glyph_index)
+            .collect();
+
+        glyph_ids.append(&mut glyph_ids_curr);
+    }
+    // Include .notdef glyph
+    glyph_ids.push(0);
+    glyph_ids.sort();
+    glyph_ids.dedup();
+
+    let subset_data = subset(&font.font_table_provider, &glyph_ids)
+        .map_err(|e| format!("Failed to subset font: {}", e))?;
 
     let new_path = [&env::var("OUT_DIR").unwrap(), out].concat();
-    let unicodes_formatted = unicodes
-        .iter()
-        .map(|u| format!("U+{}", u))
-        .collect::<Vec<String>>()
-        .join(",");
+    std::fs::write(&new_path, &subset_data)
+        .map_err(|e| format!("Failed to write subset font: {}", e))?;
 
-    // Test to see if pyftsubset is found
-    let pyftsubset_detect = run_script::run("whereis pyftsubset", &(vec![]), &ScriptOptions::new());
-    match pyftsubset_detect {
-        Ok((_i, s1, _s2)) => {
-            if s1 == "pyftsubset: " {
-                return Err(String::from("pyftsubset not found"));
-            }
-        }
-        // It was not, return an error and abort
-        Err(x) => return Err(x.to_string()),
-    }
-
-    let script_result = run_script::run(
-        &format!(
-            "pyftsubset {}/assets/{} --unicodes={}
-			mv {}/assets/{} {}",
-            env!("CARGO_MANIFEST_DIR"),
-            from,
-            unicodes_formatted,
-            env!("CARGO_MANIFEST_DIR"),
-            from.replace(".ttf", ".subset.ttf"),
-            new_path
-        ),
-        &(vec![]),
-        &ScriptOptions::new(),
-    );
-
-    if let Ok((_, _, error)) = script_result {
-        if error.is_empty() {
-            return Ok(std::fs::read(new_path).unwrap());
-        } else {
-            return Err(error);
-        }
-    } else if let Err(error) = script_result {
-        return Err(error.to_string());
-    }
-    unreachable!()
+    Ok(subset_data)
 }
 
 fn main() {