Fix some smaller issues

src/cff/cid_font.rs

@@ -135,12 +135,15 @@ pub fn rewrite_fd_index(
 
 /// Write the FD INDEX for CID-keyed fonts. They all get mapped to the font DICT 0.
 pub fn generate_fd_index(gid_remapper: &GlyphRemapper, w: &mut Writer) -> Result<()> {
-    // We always use format 0, since it's the simplest.
+    // Format
+    w.write::<u8>(3);
+    // nRanges
+    w.write::<u16>(1);
+    // first
+    w.write::<u16>(0);
+    // fd index
     w.write::<u8>(0);
-
-    for _ in 0..gid_remapper.num_gids() {
-        w.write::<u8>(0);
-    }
-
+    // sentinel
+    w.write::<u16>(gid_remapper.num_gids());
     Ok(())
 }

src/cff/dict/font_dict.rs

@@ -121,6 +121,18 @@ pub fn rewrite_font_dict_index(
 pub fn generate_font_dict_index(offsets: &mut Offsets, w: &mut Writer) -> Result<()> {
     let mut sub_w = Writer::new();
 
+    // Similarly to ghostscript, write a default font matrix. Fixes issues for some printers
+    // https://leahneukirchen.org/blog/archive/2022/10/50-blank-pages-or-black-box-debugging-of-pdf-rendering-in-printers.html
+    sub_w.write(&[
+        Number::one(),
+        Number::zero(),
+        Number::zero(),
+        Number::one(),
+        Number::zero(),
+        Number::zero(),
+    ]);
+    sub_w.write(FONT_MATRIX);
+
     // Write the length and offset of the private dict.
     // Private dicts have already been written, so the offsets are already correct.
     // This means that these two offsets are a bit special compared to the others, since
@@ -140,7 +152,7 @@ pub fn generate_font_dict_index(offsets: &mut Offsets, w: &mut Writer) -> Result
         .value
         .write_as_5_bytes(&mut sub_w);
 
-    sub_w.write(dict::operators::PRIVATE);
+    sub_w.write(PRIVATE);
     w.write(create_index(vec![sub_w.finish()])?);
 
     Ok(())

src/cff/mod.rs

@@ -132,11 +132,12 @@ impl Offsets {
 
 pub fn subset(ctx: &mut Context<'_>) -> Result<()> {
     let table = Table::parse(ctx).unwrap();
-    let sid_remapper = get_sid_remapper(&table).ok_or(SubsetError)?;
 
     // NOTE: The charstrings are already in the new order that they need be written in.
     let (char_strings, fd_remapper) = subset_charstrings(&table, &ctx.mapper)?;
 
+    let sid_remapper = get_sid_remapper(&table, &fd_remapper).ok_or(SubsetError)?;
+
     let mut offsets = match &table.font_kind {
         FontKind::Sid(_) => Offsets::new_sid(),
         FontKind::Cid(_) => Offsets::new_cid(fd_remapper.len()),
@@ -145,8 +146,7 @@ pub fn subset(ctx: &mut Context<'_>) -> Result<()> {
     let mut subsetted_font = {
         let mut w = Writer::new();
         // HEADER
-        // TODO: Update offsize
-        w.write(table.header);
+        w.write([1u8, 0, 4, 4]);
         // Name INDEX
         w.write(table.names);
         // Top DICT INDEX
@@ -301,7 +301,10 @@ fn subset_charstrings<'a>(
 }
 
 /// Get the SID remapper
-fn get_sid_remapper<'a>(table: &Table<'a>) -> Option<SidRemapper<'a>> {
+fn get_sid_remapper<'a>(
+    table: &Table<'a>,
+    fd_remapper: &FontDictRemapper,
+) -> Option<SidRemapper<'a>> {
     let mut sid_remapper = SidRemapper::new();
     sid_remapper.remap(b"Adobe");
     sid_remapper.remap(b"Identity");
@@ -334,7 +337,9 @@ fn get_sid_remapper<'a>(table: &Table<'a>) -> Option<SidRemapper<'a>> {
         // Since we turn SIDs into GIDs, nothing to do here.
         FontKind::Sid(_) => {}
         FontKind::Cid(ref cid) => {
-            for font_dict in &cid.font_dicts {
+            for font_dict in fd_remapper.sorted_iter() {
+                let font_dict = cid.font_dicts.get(font_dict as usize)?;
+
                 if let Some(font_name) = font_dict.font_name {
                     remap_sid(font_name)?;
                 }

src/cff/number.rs

@@ -102,7 +102,7 @@ impl Writeable for RealNumber {
     fn write(&self, w: &mut Writer) {
         let mut nibbles = vec![];
 
-        let string_form = format!("{:e}", self.0);
+        let string_form = format!("{}", self.0);
         let mut r = Reader::new(string_form.as_bytes());
 
         while !r.at_end() {
@@ -111,16 +111,6 @@ impl Writeable for RealNumber {
             match byte {
                 b'0'..=b'9' => nibbles.push(byte - 48),
                 b'.' => nibbles.push(0xA),
-                b'e' => {
-                    let next = r.peak::<u8>().unwrap();
-
-                    if next == b'-' {
-                        r.read::<u8>().unwrap();
-                        nibbles.push(0xC);
-                    } else {
-                        nibbles.push(0xb);
-                    }
-                }
                 b'-' => nibbles.push(0xE),
                 _ => unreachable!(),
             }

tests/src/main.rs

@@ -19,7 +19,7 @@ mod font_tools;
 type Result<T> = std::result::Result<T, Box<dyn Error>>;
 
 const FONT_TOOLS_REF: bool = false;
-const OVERWRITE_REFS: bool = true;
+const OVERWRITE_REFS: bool = false;
 
 struct TestContext {
     font: Vec<u8>,

tests/ttx/LatinModernRoman-Regular_1.ttx

@@ -14,7 +14,7 @@
     <!-- Most of this table will be recalculated by the compiler -->
     <tableVersion value="1.0"/>
     <fontRevision value="2.004"/>
-    <checkSumAdjustment value="0x3a41a448"/>
+    <checkSumAdjustment value="0xbb4babf0"/>
     <magicNumber value="0x5f0f3cf5"/>
     <flags value="00000000 00000011"/>
     <unitsPerEm value="1000"/>
@@ -112,9 +112,10 @@
       <CIDFontType value="0"/>
       <CIDCount value="65535"/>
       <!-- charset is dumped separately as the 'GlyphOrder' element -->
-      <FDSelect format="0"/>
+      <FDSelect format="3"/>
       <FDArray>
         <FontDict index="0">
+          <FontMatrix value="1 0 0 1 0 0"/>
           <Private>
             <BlueValues value="-22 0 431 448 666 677 683 705"/>
             <BlueScale value="0.04546"/>

tests/ttx/NewCMMath-Regular_1.ttx

@@ -20,7 +20,7 @@
     <!-- Most of this table will be recalculated by the compiler -->
     <tableVersion value="1.0"/>
     <fontRevision value="2.0"/>
-    <checkSumAdjustment value="0xf7280eca"/>
+    <checkSumAdjustment value="0xc9a635b6"/>
     <magicNumber value="0x5f0f3cf5"/>
     <flags value="00000000 00001011"/>
     <unitsPerEm value="1000"/>
@@ -120,9 +120,10 @@ This work is released under the GUST Font License -- see http://tug.org/fonts/li
       <CIDFontType value="0"/>
       <CIDCount value="65535"/>
       <!-- charset is dumped separately as the 'GlyphOrder' element -->
-      <FDSelect format="0"/>
+      <FDSelect format="3"/>
       <FDArray>
         <FontDict index="0">
+          <FontMatrix value="1 0 0 1 0 0"/>
           <Private>
             <BlueValues value="-22 0 431 448 666 666 677 705"/>
             <OtherBlues value="-206 -205"/>

tests/ttx/NotoSansCJKsc-Regular_1.ttx

@@ -23,7 +23,7 @@
     <!-- Most of this table will be recalculated by the compiler -->
     <tableVersion value="1.0"/>
     <fontRevision value="2.004"/>
-    <checkSumAdjustment value="0x7627ceb7"/>
+    <checkSumAdjustment value="0xf75f3f09"/>
     <magicNumber value="0x5f0f3cf5"/>
     <flags value="00000000 00000011"/>
     <unitsPerEm value="1000"/>