From 5d1aa8b81439b458aee1a515a553f6682acd66ef Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jackpot51@gmail.com>
Date: Wed, 26 Oct 2022 19:56:13 -0600
Subject: [PATCH] Add simple per-glyph wrapping option

---
 examples/syntax/src/main.rs |  1 +
 src/buffer.rs               | 24 +++++++++----
 src/shape.rs                | 67 +++++++++++++++++++++++++++++++++++++
 3 files changed, 85 insertions(+), 7 deletions(-)

diff --git a/examples/syntax/src/main.rs b/examples/syntax/src/main.rs
index 4657c9f..d258335 100644
--- a/examples/syntax/src/main.rs
+++ b/examples/syntax/src/main.rs
@@ -153,6 +153,7 @@ fn main() {
                 }
 
                 line.attrs_list = attrs_list;
+                line.wrap_simple = true;
                 line.reset();
             }
 
diff --git a/src/buffer.rs b/src/buffer.rs
index c85ded4..624a1b9 100644
--- a/src/buffer.rs
+++ b/src/buffer.rs
@@ -178,6 +178,7 @@ pub struct TextBufferLine<'a> {
     pub attrs_list: AttrsList<'a>,
     shape_opt: Option<ShapeLine>,
     layout_opt: Option<Vec<LayoutLine>>,
+    pub wrap_simple: bool,
 }
 
 impl<'a> TextBufferLine<'a> {
@@ -187,6 +188,7 @@ impl<'a> TextBufferLine<'a> {
             attrs_list,
             shape_opt: None,
             layout_opt: None,
+            wrap_simple: false,
         }
     }
 
@@ -210,13 +212,21 @@ impl<'a> TextBufferLine<'a> {
     pub fn layout(&mut self, font_system: &'a FontSystem<'a>, font_size: i32, width: i32) -> &[LayoutLine] {
         if self.layout_opt.is_none() {
             let mut layout = Vec::new();
-            let shape = self.shape(font_system);
-            shape.layout(
-                font_size,
-                width,
-                &mut layout,
-                0,
-            );
+            if self.wrap_simple {
+                self.shape(font_system).layout_simple(
+                    font_size,
+                    width,
+                    &mut layout,
+                    0,
+                );
+            } else {
+                self.shape(font_system).layout(
+                    font_size,
+                    width,
+                    &mut layout,
+                    0,
+                );
+            }
             self.layout_opt = Some(layout);
         }
         self.layout_opt.as_ref().unwrap()
diff --git a/src/shape.rs b/src/shape.rs
index 5e5c877..b1eb56c 100644
--- a/src/shape.rs
+++ b/src/shape.rs
@@ -472,6 +472,73 @@ impl ShapeLine {
         Self { rtl, spans }
     }
 
+    //TODO: combine with layout function
+    pub fn layout_simple(
+        &self,
+        font_size: i32,
+        line_width: i32,
+        layout_lines: &mut Vec<LayoutLine>,
+        mut layout_i: usize,
+    ) {
+        let mut push_line = true;
+        let mut glyphs = Vec::new();
+
+        let start_x = if self.rtl { line_width as f32 } else { 0.0 };
+        let end_x = if self.rtl { 0.0 } else { line_width as f32 };
+        let mut x = start_x;
+        let mut y = 0.0;
+        for span in self.spans.iter() {
+            for word in span.words.iter() {
+                for glyph in word.glyphs.iter() {
+                    let x_advance = font_size as f32 * glyph.x_advance;
+                    let y_advance = font_size as f32 * glyph.y_advance;
+
+                    let wrap = if self.rtl {
+                        x - x_advance < end_x
+                    } else {
+                        x + x_advance > end_x
+                    };
+
+                    if wrap {
+                        let mut glyphs_swap = Vec::new();
+                        std::mem::swap(&mut glyphs, &mut glyphs_swap);
+                        layout_lines.insert(
+                            layout_i,
+                            LayoutLine {
+                                glyphs: glyphs_swap,
+                            },
+                        );
+                        layout_i += 1;
+
+                        x = start_x;
+                        y = 0.0;
+                    }
+
+                    if self.rtl {
+                        x -= x_advance
+                    }
+
+                    glyphs.push(glyph.layout(font_size, x, y, span.rtl));
+                    push_line = true;
+
+                    if !self.rtl {
+                        x += x_advance;
+                    }
+                    y += y_advance;
+                }
+            }
+        }
+
+        if push_line {
+            layout_lines.insert(
+                layout_i,
+                LayoutLine {
+                    glyphs,
+                },
+            );
+        }
+    }
+
     pub fn layout(
         &self,
         font_size: i32,