Restore newline functionality (mostly...)

core/src/font.rs

@@ -174,24 +174,26 @@ impl<'gc> Font<'gc> {
         size
     }
 
-    /// Given a line of text, split it into the shortest number of lines that
+    /// Given a line of text, find the first breakpoint within the text.
-    /// are shorter than `width`.
     ///
     /// This function assumes only `" "` is valid whitespace to split words on,
-    /// and will not attempt to break words that are longer than `width`.
+    /// and will not attempt to break words that are longer than `width`, nor
+    /// will it break at newlines.
     ///
-    /// The given `offset` determines the start of the initial line.
+    /// The given `offset` determines the start of the initial line, while the
+    /// `width` indicates how long the line is supposed to be.
+    ///
+    /// This function yields `None` if the line is not broken.
     ///
     /// TODO: This function and, more generally, this entire file will need to
     /// be internationalized to implement AS3 `flash.text.engine`.
-    pub fn split_wrapped_lines(
+    pub fn wrap_line(
         self,
         text: &str,
         font_size: Twips,
         width: Twips,
         offset: Twips,
-    ) -> Vec<usize> {
+    ) -> Option<usize> {
-        let mut result = vec![];
         let mut current_width = width
             .checked_sub(offset)
             .unwrap_or_else(|| Twips::from_pixels(0.0));
@@ -200,29 +202,19 @@ impl<'gc> Font<'gc> {
         for word in text.split(' ') {
             let measure = self.measure(word, font_size);
             let line_start = current_word.as_ptr() as usize - text.as_ptr() as usize;
-            let line_end = if (line_start + current_word.len() + 1) < text.len() {
+            let line_end = line_start + current_word.len();
-                line_start + current_word.len() + 1
-            } else {
-                line_start + current_word.len()
-            };
             let word_start = word.as_ptr() as usize - text.as_ptr() as usize;
-            let word_end = if (word_start + word.len() + 1) < text.len() {
+            let word_end = word_start + word.len();
-                word_start + word.len() + 1
-            } else {
-                word_start + word.len()
-            };
 
             if measure.0 > current_width && measure.0 > width {
                 //Failsafe for if we get a word wider than the field.
                 if !current_word.is_empty() {
-                    result.push(line_end);
+                    return Some(line_end);
                 }
-                result.push(word_end);
+                return Some(word_end);
-                current_word = &text[word_end..word_end];
-                current_width = width;
             } else if measure.0 > current_width {
                 if !current_word.is_empty() {
-                    result.push(line_end);
+                    return Some(line_end);
                 }
 
                 current_word = &text[word_start..word_end];
@@ -233,7 +225,7 @@ impl<'gc> Font<'gc> {
             }
         }
 
-        result
+        None
     }
 
     pub fn descriptor(self) -> FontDescriptor {

core/src/html/layout.rs

@@ -44,6 +44,12 @@ impl<'gc> LayoutContext<'gc> {
         &mut self.cursor
     }
 
+    /// Adjust the text layout cursor down to the next line.
+    fn newline(&mut self, font_size: Twips) {
+        self.cursor.set_x(Twips::from_pixels(0.0));
+        self.cursor += (Twips::from_pixels(0.0), font_size).into();
+    }
+
     fn font(&self) -> Option<Font<'gc>> {
         self.font
     }
@@ -217,36 +223,48 @@ impl<'gc> LayoutBox<'gc> {
         for (start, _end, text, span) in fs.iter_spans() {
             if let Some(font) = layout_context.resolve_font(context, movie.clone(), &span) {
                 let font_size = Twips::from_pixels(span.size);
-                let breakpoint_list =
-                    font.split_wrapped_lines(&text, font_size, bounds, layout_context.cursor().x());
-
-                let end = text.len();
-
                 let mut last_breakpoint = 0;
 
-                for breakpoint in breakpoint_list {
+                while let Some(breakpoint) = font.wrap_line(
-                    if last_breakpoint != breakpoint {
+                    &text[last_breakpoint..],
-                        Self::append_text_fragment(
+                    font_size,
-                            context.gc_context,
+                    bounds,
-                            &mut layout_context,
+                    layout_context.cursor().x(),
-                            &text[last_breakpoint..breakpoint],
+                ) {
-                            start + last_breakpoint,
+                    if breakpoint == last_breakpoint {
-                            start + breakpoint,
+                        last_breakpoint += 1;
-                            span,
+                        continue;
-                        );
                     }
 
+                    Self::append_text_fragment(
+                        context.gc_context,
+                        &mut layout_context,
+                        &text[last_breakpoint..breakpoint],
+                        start + last_breakpoint,
+                        start + breakpoint,
+                        span,
+                    );
+
                     last_breakpoint = breakpoint;
+                    if last_breakpoint >= text.len() {
+                        break;
+                    }
+
+                    layout_context.newline(font_size);
                 }
 
-                Self::append_text_fragment(
+                let span_end = text.len();
-                    context.gc_context,
+
-                    &mut layout_context,
+                if last_breakpoint < span_end {
-                    &text[last_breakpoint..end],
+                    Self::append_text_fragment(
-                    start + last_breakpoint,
+                        context.gc_context,
-                    start + end,
+                        &mut layout_context,
-                    span,
+                        &text[last_breakpoint..span_end],
-                );
+                        start + last_breakpoint,
+                        start + span_end,
+                        span,
+                    );
+                }
             }
         }