Bullets: an installed symbol font draws its own glyph (#293)

Bullets in Wingdings, Wingdings 2/3, Symbol and other symbol fonts were
always swapped for a look-alike from one Wingdings table, so a Wingdings 2
star (0xEA) became a round dot. When the deck's symbol font is installed,
its glyph is drawn (symbol fonts map character codes at U+F000 + code), as
PowerPoint does; otherwise Wingdings 2 and 3 codes get their own
look-alikes.

Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

crates/text/src/lib.rs

@@ -493,6 +493,17 @@ fn shape_para(ctx: &Ctx, shape: &Shape, body: &TextBody, pi: usize, scale: f64,
                 // Symbol fonts (Wingdings) aren't available: map common private-use bullets.
                 let ch = map_symbol_bullet(char, props.bullet_font.as_deref());
                 bullet_face(db, &mut st, &ch);
+
+                // A symbol font (Wingdings, Symbol…) that is installed draws its own glyph, found
+                // at U+F000 + the character code as such fonts map them; otherwise common symbol
+                // bullets are mapped to Unicode look-alikes.
+                let ch = match symbol_font_char(&st.face, char, props.bullet_font.as_deref()) {
+                    Some(c) => c.to_string(),
+                    None => map_symbol_bullet(char, props.bullet_font.as_deref()),
+                };
+                if !st.face.covers(ch.chars().next().unwrap_or('•')) {
+                    st.face = db.face("Inter", "Regular");
+                }
                 Some((ch, st))
             }
             Some(Bullet::AutoNum { scheme, start_at }) => {
@@ -715,11 +726,59 @@ fn shape_item(
     }
 }
 
+/// Is `family` a symbol font (characters at U+F000 + code)?
+fn is_symbol_font(family: &str) -> bool {
+    let f = family.to_ascii_lowercase();
+    f.starts_with("wingdings") || f == "symbol" || f.starts_with("webdings") || f.starts_with("marlett")
+}
+
+/// The character to draw bullet `c` with the installed symbol font `face`, when `font` names a
+/// symbol font that `face` is (not a substitute) and it has the glyph.
+fn symbol_font_char(face: &FontFace, c: &str, font: Option<&str>) -> Option<char> {
+    let font = font?;
+    if !is_symbol_font(font) || !face.family.eq_ignore_ascii_case(font) {
+        return None;
+    }
+    let first = c.chars().next()?;
+    let pua = char::from_u32(0xF000 | ((first as u32) & 0xFF))?;
+    if face.covers(pua) {
+        Some(pua)
+    } else if face.covers(first) {
+        Some(first)
+    } else {
+        None
+    }
+}
+
 fn map_symbol_bullet(c: &str, font: Option<&str>) -> String {
     let f = font.unwrap_or("").to_ascii_lowercase();
     let first = c.chars().next().unwrap_or('•');
     if f.contains("wingdings") || f.contains("symbol") || ('\u{f000}'..='\u{f0ff}').contains(&first) {
         let code = (first as u32) & 0xff;
+        // Wingdings 2 and 3 put different shapes at the same codes.
+        if f.starts_with("wingdings 2") {
+            let m = match code {
+                0x97 | 0x98 => '●',
+                0x9e..=0xa1 => '■',
+                0xa2..=0xa5 => '◆',
+                0xea..=0xf3 => '★',
+                0xb7..=0xbf => '○',
+                0x50 => '✓',
+                _ => '•',
+            };
+            return m.to_string();
+        }
+        if f.starts_with("wingdings 3") {
+            let m = match code {
+                0x7d | 0x75 => '►',
+                0x7c | 0x74 => '◄',
+                0x70 => '▲',
+                0x71 => '▼',
+                0xc6 | 0xc7 => '➔',
+                _ => '▶',
+            };
+            return m.to_string();
+        }
         let m = match code {
             0xa7 => '▪',
             0xd8 => '➢',

crates/text/src/tests.rs

@@ -624,3 +624,28 @@ fn a_bullet_the_text_font_lacks_falls_back_to_a_face_that_has_it() {
         assert!(b.glyphs.iter().all(|g| g.0 != 0), "no missing-glyph box");
     }
 }
+
+#[test]
+fn symbol_font_bullets_map_by_font() {
+    // Wingdings 2 code 0xEA is a star, Wingdings 3 0x7D a right-pointing triangle; plain
+    // Wingdings keeps its own table (0xA7 is a small square).
+    let star = String::from_utf8(vec![0xEF, 0x83, 0xAA]).unwrap(); // U+F0EA
+    assert_eq!(map_symbol_bullet(&star, Some("Wingdings 2")), "★");
+    assert_eq!(map_symbol_bullet("\u{7d}", Some("Wingdings 3")), "►");
+    assert_eq!(map_symbol_bullet("\u{f0a7}", Some("Wingdings")), "▪");
+    assert_eq!(map_symbol_bullet("•", Some("Arial")), "•");
+    assert!(is_symbol_font("Wingdings 2") && is_symbol_font("Symbol") && !is_symbol_font("Arial"));
+}
+
+#[test]
+fn an_installed_symbol_font_draws_its_own_bullet() {
+    // Where the deck's symbol font is installed, its glyph is drawn (as PowerPoint does), not a
+    // look-alike. Skipped without Wingdings 2.
+    let db = FontDb::global();
+    if !db.has_family("Wingdings 2") {
+        return;
+    }
+    let face = db.face("Wingdings 2", "Regular");
+    assert_eq!(symbol_font_char(&face, "\u{ea}", Some("Wingdings 2")), Some('\u{f0ea}'));
+    assert_eq!(symbol_font_char(&face, "\u{ea}", Some("Arial")), None);
+}