Link to forgejo dep

examples/hello-world.rs

@@ -1,6 +1,6 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
 
-use std::sync::Arc;
+use std::{ops::Deref, sync::Arc};
 
 use eframe::{
     egui::{self, Slider},
@@ -11,11 +11,12 @@ use eframe::{
     },
     CreationContext,
 };
+use egui::{Align2, Pos2};
 use egui_glyphon::{
     glyphon::{Attrs, Family, FontSystem, Metrics, Shaping},
     BufferWithTextArea, GlyphonRenderer, GlyphonRendererCallback,
 };
-use glyphon::Buffer;
+use glyphon::{cosmic_text::Align, Buffer};
 
 fn main() -> Result<(), eframe::Error> {
     env_logger::init(); // Log to stderr (if you run with `RUST_LOG=debug`).
@@ -32,28 +33,26 @@ fn main() -> Result<(), eframe::Error> {
 
 struct MyApp {
     font_system: Arc<Mutex<FontSystem>>,
-    size: f32,
-    buffer: Arc<RwLock<Buffer>>,
+    buffers: Vec<Arc<RwLock<Buffer>>>,
 }
 
 impl Default for MyApp {
     fn default() -> Self {
         let mut font_system = FontSystem::new();
-        let mut buffer =
-            egui_glyphon::glyphon::Buffer::new(&mut font_system, Metrics::new(30.0, 42.0));
+        let buffers = cosmic_jotdown::jotdown_into_buffers(
+            r#"# Header
+
+Test _test_ *test* 'test' "`test`""#,
+            &mut font_system,
+            Metrics::new(30.0, 42.0),
+            f32::MAX,
+        )
+        .map(|buffer| Arc::new(RwLock::new(buffer)))
+        .collect();
 
-        buffer.set_size(&mut font_system, 16.0, 9.0);
-        buffer.set_text(&mut font_system, "<== Hello world! ==> 👋\nThis is rendered with 🦅 glyphon 🦁\nThe text below should be partially clipped.\na b c d e f g h i j k l m n o p q r s t u v w x y z fi ffi 🐕‍🦺 fi ffi
-        fi تما 🐕‍🦺 ffi تما
-        ffi fi 🐕‍🦺 ffi fi
-        تما تما 🐕‍🦺 تما
-        تما ffi 🐕‍🦺 تما fi تما
-        تما تما 🐕‍🦺 تما", Attrs::new().family(Family::SansSerif), Shaping::Advanced);
-        buffer.shape_until_scroll(&mut font_system);
         Self {
             font_system: Arc::new(Mutex::new(font_system)),
-            buffer: Arc::new(RwLock::new(buffer)),
-            size: 35.0,
+            buffers,
         }
     }
 }
@@ -70,28 +69,56 @@ impl MyApp {
     }
 }
 
+pub fn measure_buffer(buffer: &Buffer, vb: Vec2) -> Rect {
+    let mut rtl = false;
+    let (width, total_lines) =
+        buffer
+            .layout_runs()
+            .fold((0.0, 0usize), |(width, total_lines), run| {
+                if run.rtl {
+                    rtl = true;
+                }
+                (run.line_w.max(width), total_lines + 1)
+            });
+
+    let (max_width, max_height) = buffer.size();
+
+    let size = Vec2::new(
+        if rtl { vb.x } else { width.min(max_width) },
+        (total_lines as f32 * buffer.metrics().line_height).min(max_height),
+    );
+    match buffer.lines[0].align() {
+        Some(Align::Right) | Some(Align::End) => {
+            Align2::RIGHT_TOP.align_size_within_rect(size, Rect::from_min_size(Pos2::ZERO, vb))
+        }
+        Some(Align::Center) | Some(Align::Justified) => {
+            Align2::CENTER_TOP.align_size_within_rect(size, Rect::from_min_size(Pos2::ZERO, vb))
+        }
+        Some(Align::Left) | None => Rect::from_min_size(Pos2::ZERO, size),
+    }
+}
+
 impl eframe::App for MyApp {
     fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
-        let size = Vec2::new(16.0 * self.size, 9.0 * self.size);
-
-        {
-            let mut font_system = self.font_system.lock();
-            let mut buffer = self.buffer.write();
-            buffer.set_metrics(&mut font_system, Metrics::new(self.size, self.size));
-            buffer.set_size(&mut font_system, size.x, size.y);
-            buffer.shape_until_scroll(&mut font_system);
-        }
-
         egui::CentralPanel::default().show(ctx, |ui| {
-            ui.add(Slider::new(&mut self.size, 0.1..=67.5));
-            let rect = Rect::from_min_size(ui.cursor().min, size);
-            let buffers: Vec<BufferWithTextArea> = vec![BufferWithTextArea::new(
-                self.buffer.clone(),
-                rect,
-                1.0,
-                egui_glyphon::glyphon::Color::rgb(255, 255, 255),
-                ui.ctx(),
-            )];
+            let mut rect = Rect::from_min_size(ui.cursor().min, Vec2::INFINITY);
+            let buffers: Vec<BufferWithTextArea> = self
+                .buffers
+                .iter()
+                .cloned()
+                .map(|buffer| {
+                    let buffer_size = measure_buffer(buffer.read().deref(), ui.max_rect().size());
+                    let this_rect = rect;
+                    rect.min.y += buffer_size.height() + 48.0;
+                    BufferWithTextArea::new(
+                        buffer,
+                        this_rect,
+                        1.0,
+                        egui_glyphon::glyphon::Color::rgb(255, 255, 255),
+                        ui.ctx(),
+                    )
+                })
+                .collect();
             ui.painter().add(egui_wgpu::Callback::new_paint_callback(
                 ui.max_rect(),
                 GlyphonRendererCallback { buffers },