Layout: end manual tate-chu-yoko at soft return, and use separator metrics for empty continuation line

crates/text/src/layout/flow.rs

@@ -392,6 +392,13 @@ fn run_paragraph_lines(cx: &mut Ctx<'_>, pen: &mut Pen<'_>, t: &TextObject, mut
     let mut index = 0;
     let mut emitted_empty_continuation = false;
     loop {
+        let pm = if index >= n
+            && let Some(last) = paragraph.sg.last()
+        {
+            Metrics::of(last)
+        } else {
+            paragraph.pm
+        };
         let mut placement = PlacementContext {
             para: paragraph.para,
             pr: &paragraph.pr,
@@ -399,7 +406,7 @@ fn run_paragraph_lines(cx: &mut Ctx<'_>, pen: &mut Pen<'_>, t: &TextObject, mut
             continued: paragraph.continued,
             rtl: paragraph.rtl,
             mirror: paragraph.mirror,
-            pm: paragraph.pm,
+            pm,
             composed: &paragraph.composed,
             hyphen_run,
             hyphen_limit: paragraph.hyphen_limit,

crates/text/src/layout/vertical.rs

@@ -23,7 +23,7 @@ pub(super) fn whole_character_widths(glyphs: &mut [SGlyph]) {
 /// before the automatic digit rule.
 /// <https://helpx.adobe.com/illustrator/using/formatting-asian-characters.html>
 pub(super) fn tate_chu_yoko(g: &mut [SGlyph], style: impl Fn(&SGlyph) -> (f64, bool)) {
-    let manual: Vec<bool> = g.iter().map(|gl| style(gl).1).collect();
+    let manual: Vec<bool> = g.iter().map(|gl| gl.ch != '\u{2028}' && style(gl).1).collect();
     let digits: Vec<bool> = g.iter().map(|gl| gl.inline.is_none() && gl.ch.is_ascii_digit()).collect();
     let mut i = 0;
     while i < g.len() {