[klippa] subset name table

klippa/src/lib.rs

@@ -9,6 +9,7 @@ mod head;
 mod hmtx;
 mod layout;
 mod maxp;
+mod name;
 mod os2;
 mod parsing_util;
 mod post;
@@ -17,6 +18,7 @@ use glyf_loca::subset_glyf_loca;
 use head::subset_head;
 use hmtx::subset_hmtx_hhea;
 use maxp::subset_maxp;
+use name::subset_name;
 use os2::subset_os2;
 pub use parsing_util::{
     parse_drop_tables, parse_name_ids, parse_name_languages, parse_unicodes, populate_gids,
@@ -541,6 +543,8 @@ fn subset_table<'a>(
 
         Maxp::TAG => subset_maxp(font, plan, builder),
 
+        Name::TAG => subset_name(font, plan, builder),
+
         Os2::TAG => subset_os2(font, plan, builder),
 
         Post::TAG => subset_post(font, plan, builder),

klippa/src/name.rs

@@ -0,0 +1,123 @@
+//! impl subset() for name table
+
+use std::cmp::Ordering;
+
+use crate::{
+    Plan,
+    SubsetError::{self, SubsetTableError},
+    SubsetFlags,
+};
+
+use write_fonts::{
+    read::{tables::name::Name, FontRef, TableProvider, TopLevelTable},
+    FontBuilder,
+};
+
+// reference: subset() for name table in harfbuzz
+// https://github.com/harfbuzz/harfbuzz/blob/main/src/OT/name/name.hh#L387
+pub(crate) fn subset_name(
+    font: &FontRef,
+    plan: &Plan,
+    builder: &mut FontBuilder,
+) -> Result<(), SubsetError> {
+    let name = font.name().or(Err(SubsetTableError(Name::TAG)))?;
+    let name_records = name.name_record();
+    //TODO: support name_table_override
+    //TODO: support name table version 1
+    let mut retained_name_record_idxes = name_records
+        .iter()
+        .enumerate()
+        .filter(|(_, record)| {
+            if !plan.name_ids.contains(record.name_id())
+                || !plan.name_languages.contains(record.language_id())
+            {
+                return false;
+            }
+            plan.subset_flags
+                .contains(SubsetFlags::SUBSET_FLAGS_NAME_LEGACY)
+                || record.is_unicode()
+        })
+        .map(|x| x.0)
+        .collect::<Vec<_>>();
+
+    retained_name_record_idxes.sort_unstable_by(|a, b| {
+        let id_a = name_records[*a].platform_id();
+        let id_b = name_records[*b].platform_id();
+        if id_a != id_b {
+            return id_a.cmp(&id_b);
+        }
+
+        let id_a = name_records[*a].encoding_id();
+        let id_b = name_records[*b].encoding_id();
+        if id_a != id_b {
+            return id_a.cmp(&id_b);
+        }
+
+        let id_a = name_records[*a].language_id();
+        let id_b = name_records[*b].language_id();
+        if id_a != id_b {
+            return id_a.cmp(&id_b);
+        }
+
+        let id_a = name_records[*a].name_id().to_u16();
+        let id_b = name_records[*b].name_id().to_u16();
+        if id_a != id_b {
+            return id_a.cmp(&id_b);
+        }
+
+        let len_a = name_records[*a].length();
+        let len_b = name_records[*b].length();
+        if len_a != len_b {
+            return len_a.cmp(&len_b);
+        }
+
+        Ordering::Equal
+    });
+
+    let name_data = name.offset_data().as_bytes();
+    let mut out = Vec::with_capacity(name_data.len());
+    // version
+    // TODO: support version 1
+    out.extend_from_slice(&[0, 0]);
+    //count
+    let count = retained_name_record_idxes.len() as u16;
+    out.extend_from_slice(&count.to_be_bytes());
+    //storage_offset
+    let storage_offset = count * 12 + 6;
+    out.extend_from_slice(&storage_offset.to_be_bytes());
+
+    //pre-allocate space for name records array
+    out.resize(storage_offset as usize, 0);
+
+    let mut string_offset = 0_u16;
+    let storage_start = name.storage_offset() as usize;
+    for (new_idx, old_idx) in retained_name_record_idxes.iter().enumerate() {
+        let old_record_start = 6 + 12 * old_idx;
+        let new_record_start = 6 + 12 * new_idx;
+        //copy name_record except for string offset
+        out.get_mut(new_record_start..new_record_start + 10)
+            .unwrap()
+            .copy_from_slice(
+                name_data
+                    .get(old_record_start..old_record_start + 10)
+                    .unwrap(),
+            );
+        //copy string offset
+        out.get_mut(new_record_start + 10..new_record_start + 12)
+            .unwrap()
+            .copy_from_slice(&string_offset.to_be_bytes());
+
+        //copy string data
+        let str_start = storage_start + name_records[*old_idx].string_offset().to_u32() as usize;
+        let str_len = name_records[*old_idx].length();
+        let str_data = name_data
+            .get(str_start..str_start + str_len as usize)
+            .ok_or(SubsetTableError(Name::TAG))?;
+        out.extend_from_slice(str_data);
+
+        string_offset += str_len;
+    }
+
+    builder.add_raw(Name::TAG, out);
+    Ok(())
+}

klippa/test-data/profiles/gids.txt

@@ -0,0 +1 @@
+--gids=1,2,3

klippa/test-data/profiles/name-ids.txt

@@ -0,0 +1 @@
+--name-IDs=0,1,2

klippa/test-data/profiles/name-languages.txt

@@ -0,0 +1 @@
+--name-languages=*

klippa/test-data/profiles/name-legacy.txt

@@ -0,0 +1 @@
+--name-legacy

klippa/test-data/tests/basics.tests

@@ -9,6 +9,10 @@ drop-hints.txt
 drop-hints-retain-gids.txt
 retain-gids.txt
 notdef-outline.txt
+name-ids.txt
+name-languages.txt
+name-legacy.txt
+gids.txt
 no-prune-unicode-ranges.txt
 glyph-names.txt
 retain-gids-glyph-names.txt