A foundation for text editing and selection in Masonry (#241)

This brings in a lot of the old work from Druid and Masonry (prior to
linebender/masonry#56) on text, as well as some types from Glazier.

Needed work:
- [X] Text display using abstract types
- [x] Text selection with mouse
- [x] Text input with keyboard
- [ ] IME integration (of the kind winit understands)

Follow up work:
- [ ] Keyboard control of the selection area (hard-coded hotkeys)
- [ ] [Proper
placement](https://raphlinus.github.io/text/2020/10/26/text-layout.html#shaping-cluster)
of cursor
- [ ] Input methods
- [ ] Proper hotkey handling
- [ ] Copy and/or paste

crates/masonry/Cargo.toml

@@ -30,6 +30,9 @@ pollster = "0.3.0"
 parley.workspace = true
 wgpu = { version = "0.19.3" }
 winit.workspace = true
+unicode-segmentation = "1.11.0"
+# TODO: Is this still the most up-to-date crate for this?
+xi-unicode = "0.3.0"
 
 [dev-dependencies]
 float-cmp = { version = "0.8.0", features = ["std"], default-features = false }

crates/masonry/examples/calc.rs

@@ -222,9 +222,9 @@ impl AppDriver for CalcState {
         ctx.get_root::<Flex>()
             .child_mut(1)
             .unwrap()
-            .downcast::<Label>()
+            .downcast::<Label<String>>()
             .unwrap()
-            .set_text(self.value.clone());
+            .set_text((&*self.value).into());
     }
 }
 

crates/masonry/examples/custom_widget.rs

@@ -105,14 +105,16 @@ impl Widget for CustomWidget {
             FontFamily::Generic(parley::style::GenericFamily::Serif),
         )));
         text_layout_builder.push_default(&StyleProperty::FontSize(24.0));
-        text_layout_builder.push_default(&StyleProperty::Brush(Brush::Solid(fill_color)));
+        text_layout_builder.push_default(&StyleProperty::Brush(Brush::Solid(fill_color).into()));
 
         let mut text_layout = text_layout_builder.build();
         text_layout.break_all_lines(None, Alignment::Start);
 
+        let mut scratch_scene = Scene::new();
         // We can pass a transform matrix to rotate the text we render
         masonry::text_helpers::render_text(
             scene,
+            &mut scratch_scene,
             Affine::rotate(std::f64::consts::FRAC_PI_4).then_translate((80.0, 40.0).into()),
             &text_layout,
         );

crates/masonry/src/event_loop_runner.rs

@@ -76,9 +76,27 @@ impl ApplicationHandler for MainState<'_> {
                     .handle_window_event(WindowEvent::Resize(size));
             }
             WinitWindowEvent::ModifiersChanged(modifiers) => {
+                self.pointer_state.mods = modifiers;
                 self.render_root
                     .handle_text_event(TextEvent::ModifierChange(modifiers.state()));
             }
+            WinitWindowEvent::KeyboardInput {
+                device_id: _,
+                event,
+                is_synthetic: _,
+            } => {
+                self.render_root.handle_text_event(TextEvent::KeyboardKey(
+                    event,
+                    self.pointer_state.mods.state(),
+                ));
+            }
+            WinitWindowEvent::Ime(ime) => {
+                self.render_root.handle_text_event(TextEvent::Ime(ime));
+            }
+            WinitWindowEvent::Focused(new_focus) => {
+                self.render_root
+                    .handle_text_event(TextEvent::FocusChange(new_focus));
+            }
             WinitWindowEvent::CursorMoved { position, .. } => {
                 self.pointer_state.physical_position = position;
                 self.pointer_state.position = position.to_logical(self.window.scale_factor());

crates/masonry/src/lib.rs

@@ -104,6 +104,7 @@ pub mod paint_scene_helpers;
 pub mod promise;
 pub mod render_root;
 pub mod testing;
+// mod text;
 pub mod text_helpers;
 pub mod theme;
 pub mod widget;
@@ -113,6 +114,7 @@ pub mod app_driver;
 pub mod debug_logger;
 pub mod debug_values;
 pub mod event_loop_runner;
+pub mod text2;
 
 pub use action::Action;
 pub use box_constraints::BoxConstraints;

crates/masonry/src/render_root.rs

@@ -464,8 +464,8 @@ impl RenderRoot {
         // Only send RouteFocusChanged in case there's actual change
         if old != new {
             let event = LifeCycle::Internal(InternalLifeCycle::RouteFocusChanged { old, new });
-            self.root_lifecycle(event);
             self.state.focused_widget = new;
+            self.root_lifecycle(event);
 
             // TODO - Handle IME
             // Send TextFieldFocused(focused_widget) signal

crates/masonry/src/text/README.md

@@ -0,0 +1,6 @@
+# Old Text code
+
+This folder contains code which was previously used for handling text in Masonry and Druid.
+This is provided for reference.
+
+The expectation is that this will be adapted into the versions in `text2`, then this will be deleted and `text2` will be renamed to text.