Add ViewportWidget

editor/src/main.rs

@@ -68,6 +68,9 @@ impl Application {
 
         let render_state = render::RenderState::new(device.clone(), queue.clone(), config.format);
 
+        let image = egui::ColorImage::example();
+        let viewport_texture = egui_ctx.load_texture("example_viewport", image);
+
         Self {
             window,
             device,
@@ -78,7 +81,7 @@ impl Application {
             egui_state,
             egui_ctx,
             egui_rp,
-            ui: ui::UserInterface::new(),
+            ui: ui::UserInterface::new(viewport_texture),
             render_state,
         }
     }

editor/src/ui.rs

@@ -4,16 +4,18 @@ pub struct UserInterface {
     quit: bool,
     show_about: bool,
     log_contents: String,
+    viewport: ViewportWidget,
 }
 
 impl UserInterface {
-    pub fn new() -> Self {
+    pub fn new(viewport_texture: egui::TextureHandle) -> Self {
         Self {
             developer_mode: true,
             show_profiler: false,
             quit: false,
             show_about: false,
             log_contents: "Hello logging!\n".to_string(),
+            viewport: ViewportWidget::new(viewport_texture),
         }
     }
 
@@ -117,6 +119,38 @@ impl UserInterface {
                     });
             });
 
-        egui::CentralPanel::default().show(ctx, |ui| {});
+        egui::CentralPanel::default().show(ctx, |ui| {
+            ui.add(&mut self.viewport);
+            ui.heading("Viewport");
+        });
+    }
+}
+
+pub struct ViewportWidget {
+    texture: egui::TextureHandle,
+}
+
+impl ViewportWidget {
+    pub fn new(texture: egui::TextureHandle) -> Self {
+        Self { texture }
+    }
+}
+
+impl egui::Widget for &mut ViewportWidget {
+    fn ui(self, ui: &mut egui::Ui) -> egui::Response {
+        ui.style_mut().spacing.window_margin = egui::style::Margin::same(0.0);
+        let rect = ui.max_rect();
+        let id = egui::Id::new("viewport_widget");
+        let sense = egui::Sense::click_and_drag();
+        let response = ui.interact(rect, id, sense);
+
+        use egui::{pos2, Mesh, Rect, Color32, Shape};
+        let mut mesh = Mesh::with_texture(self.texture.id());
+        let uv = Rect::from_min_max(pos2(0.0, 0.0), pos2(1.0, 1.0));
+        let tint = Color32::WHITE;
+        mesh.add_rect_with_uv(rect, uv, tint);
+        ui.painter().add(Shape::mesh(mesh));
+
+        response
     }
 }