Add debug wireframe rendering support

platform/src/context.rs

@@ -6,6 +6,62 @@ use raidillon_assets::ModelManagerRef;
 use raidillon_core::EguiQueue;
 use crate::settings::Settings;
 
+/// a single debug wireframe vertex with position and color
+#[derive(Clone, Copy)]
+pub struct DebugWireframeVertex {
+    pub position: [f32; 3],
+    pub color: [f32; 4],
+}
+
+/// shared buffer for debug wireframe rendering
+#[derive(Clone, Default)]
+pub struct DebugWireframes {
+    pub vertices: Vec<DebugWireframeVertex>,
+    pub enabled: bool,
+}
+
+impl DebugWireframes {
+    pub fn new() -> Self {
+        Self { vertices: Vec::new(), enabled: true }
+    }
+
+    pub fn clear(&mut self) {
+        self.vertices.clear();
+    }
+
+    /// add a single line segment
+    pub fn add_line(&mut self, start: [f32; 3], end: [f32; 3], color: [f32; 4]) {
+        self.vertices.push(DebugWireframeVertex { position: start, color });
+        self.vertices.push(DebugWireframeVertex { position: end, color });
+    }
+
+    /// add a wireframe box from min/max corners
+    pub fn add_box(&mut self, min: [f32; 3], max: [f32; 3], color: [f32; 4]) {
+        let [x0, y0, z0] = min;
+        let [x1, y1, z1] = max;
+
+        // bottom face edges
+        self.add_line([x0, y0, z0], [x1, y0, z0], color);
+        self.add_line([x1, y0, z0], [x1, y0, z1], color);
+        self.add_line([x1, y0, z1], [x0, y0, z1], color);
+        self.add_line([x0, y0, z1], [x0, y0, z0], color);
+
+        // top face edges
+        self.add_line([x0, y1, z0], [x1, y1, z0], color);
+        self.add_line([x1, y1, z0], [x1, y1, z1], color);
+        self.add_line([x1, y1, z1], [x0, y1, z1], color);
+        self.add_line([x0, y1, z1], [x0, y1, z0], color);
+
+        // vertical edges
+        self.add_line([x0, y0, z0], [x0, y1, z0], color);
+        self.add_line([x1, y0, z0], [x1, y1, z0], color);
+        self.add_line([x1, y0, z1], [x1, y1, z1], color);
+        self.add_line([x0, y0, z1], [x0, y1, z1], color);
+    }
+}
+
+pub type DebugWireframesRef = Rc<RefCell<DebugWireframes>>;
+
 #[derive(Clone)]
 pub struct PlatformContext {
     pub current_event: Event<()>,
@@ -16,8 +72,9 @@ pub struct PlatformContext {
     pub window: Arc<Mutex<winit::window::Window>>,
     pub egui_queue: Rc<RefCell<EguiQueue>>,
     pub settings: Arc<RwLock<Settings>>,
-    /// Sets whether or not egui will receive input events.
-    /// Added to prevent the mouse state conflict between the engine and egui.
+    /// shared debug wireframe buffer
+    pub debug_wireframes: DebugWireframesRef,
+    /// sets whether or not egui will receive input events
     pub should_egui_receive_input_events: Rc<Cell<bool>>,
 }
 

platform/src/lib.rs

@@ -6,4 +6,4 @@ pub mod settings;
 
 pub use platform::Platform;
 pub use camera::Camera;
-pub use context::{PlatformContext, TimeContext};
+pub use context::{PlatformContext, TimeContext, DebugWireframes, DebugWireframesRef, DebugWireframeVertex};