feat: enhance debug visuals with cursor-based effect

src/app.rs

@@ -1,6 +1,7 @@
 use std::time::{Duration, Instant};
 
 use anyhow::{anyhow, Result};
+use glam::Vec2;
 use sdl2::event::{Event, WindowEvent};
 use sdl2::keyboard::Keycode;
 use sdl2::render::{Canvas, ScaleMode, Texture, TextureCreator};
@@ -19,6 +20,7 @@ pub struct App<'a> {
     backbuffer: Texture<'a>,
     paused: bool,
     last_tick: Instant,
+    cursor_pos: Vec2,
 }
 
 impl App<'_> {
@@ -56,7 +58,7 @@ impl App<'_> {
 
         // Initial draw
         game.draw(&mut canvas, &mut backbuffer)?;
-        game.present_backbuffer(&mut canvas, &backbuffer)?;
+        game.present_backbuffer(&mut canvas, &backbuffer, glam::Vec2::ZERO)?;
 
         Ok(Self {
             game,
@@ -65,6 +67,7 @@ impl App<'_> {
             backbuffer,
             paused: false,
             last_tick: Instant::now(),
+            cursor_pos: Vec2::ZERO,
         })
     }
 
@@ -109,6 +112,10 @@ impl App<'_> {
                     Event::KeyDown { keycode, .. } => {
                         self.game.keyboard_event(keycode.unwrap());
                     }
+                    Event::MouseMotion { x, y, .. } => {
+                        // Convert window coordinates to logical coordinates
+                        self.cursor_pos = Vec2::new(x as f32, y as f32);
+                    }
                     _ => {}
                 }
             }
@@ -121,7 +128,10 @@ impl App<'_> {
                 if let Err(e) = self.game.draw(&mut self.canvas, &mut self.backbuffer) {
                     error!("Failed to draw game: {e}");
                 }
-                if let Err(e) = self.game.present_backbuffer(&mut self.canvas, &self.backbuffer) {
+                if let Err(e) = self
+                    .game
+                    .present_backbuffer(&mut self.canvas, &self.backbuffer, self.cursor_pos)
+                {
                     error!("Failed to present backbuffer: {e}");
                 }
             }

src/game.rs

@@ -108,10 +108,16 @@ impl Game {
         Ok(())
     }
 
-    pub fn present_backbuffer<T: RenderTarget>(&mut self, canvas: &mut Canvas<T>, backbuffer: &Texture) -> Result<()> {
+    pub fn present_backbuffer<T: RenderTarget>(
+        &mut self,
+        canvas: &mut Canvas<T>,
+        backbuffer: &Texture,
+        cursor_pos: glam::Vec2,
+    ) -> Result<()> {
         canvas.copy(backbuffer, None, None).map_err(anyhow::Error::msg)?;
         if self.debug_mode {
-            self.map.debug_render_nodes(canvas);
+            self.map
+                .debug_render_with_cursor(canvas, &mut self.text_texture, &mut self.atlas, cursor_pos);
         }
         self.draw_hud(canvas)?;
         canvas.present();

src/map/builder.rs

@@ -184,13 +184,18 @@ impl Map {
         MapRenderer::render_map(canvas, atlas, map_texture);
     }
 
-    /// Renders a debug visualization of the navigation graph.
+    /// Renders a debug visualization with cursor-based highlighting.
     ///
-    /// This function is intended for development and debugging purposes. It draws the
+    /// This function provides interactive debugging by highlighting the nearest node
-    /// nodes and edges of the graph on top of the map, allowing for visual
+    /// to the cursor, showing its ID, and highlighting its connections.
-    /// inspection of the navigation paths.
+    pub fn debug_render_with_cursor<T: RenderTarget>(
-    pub fn debug_render_nodes<T: RenderTarget>(&self, canvas: &mut Canvas<T>) {
+        &self,
-        MapRenderer::debug_render_nodes(&self.graph, canvas);
+        canvas: &mut Canvas<T>,
+        text_renderer: &mut crate::texture::text::TextTexture,
+        atlas: &mut SpriteAtlas,
+        cursor_pos: glam::Vec2,
+    ) {
+        MapRenderer::debug_render_with_cursor(&self.graph, canvas, text_renderer, atlas, cursor_pos);
     }
 
     /// Builds the house structure in the graph.

src/map/render.rs

@@ -1,6 +1,8 @@
 //! Map rendering functionality.
 
 use crate::texture::sprite::{AtlasTile, SpriteAtlas};
+use crate::texture::text::TextTexture;
+use glam::Vec2;
 use sdl2::pixels::Color;
 use sdl2::rect::{Point, Rect};
 use sdl2::render::{Canvas, RenderTarget};
@@ -23,45 +25,93 @@ impl MapRenderer {
         let _ = map_texture.render(canvas, atlas, dest);
     }
 
-    /// Renders a debug visualization of the navigation graph.
+    /// Renders a debug visualization with cursor-based highlighting.
     ///
-    /// This function is intended for development and debugging purposes. It draws the
+    /// This function provides interactive debugging by highlighting the nearest node
-    /// nodes and edges of the graph on top of the map, allowing for visual
+    /// to the cursor, showing its ID, and highlighting its connections.
-    /// inspection of the navigation paths.
+    pub fn debug_render_with_cursor<T: RenderTarget>(
-    pub fn debug_render_nodes<T: RenderTarget>(graph: &crate::entity::graph::Graph, canvas: &mut Canvas<T>) {
+        graph: &crate::entity::graph::Graph,
+        canvas: &mut Canvas<T>,
+        text_renderer: &mut TextTexture,
+        atlas: &mut SpriteAtlas,
+        cursor_pos: Vec2,
+    ) {
+        // Find the nearest node to the cursor
+        let nearest_node = Self::find_nearest_node(graph, cursor_pos);
+
+        // Draw all connections in blue
+        canvas.set_draw_color(Color::RGB(0, 0, 128)); // Dark blue for regular connections
         for i in 0..graph.node_count() {
             let node = graph.get_node(i).unwrap();
             let pos = node.position + crate::constants::BOARD_PIXEL_OFFSET.as_vec2();
 
-            // Draw connections
-            canvas.set_draw_color(Color::BLUE);
-
             for edge in graph.adjacency_list[i].edges() {
                 let end_pos = graph.get_node(edge.target).unwrap().position + crate::constants::BOARD_PIXEL_OFFSET.as_vec2();
                 canvas
                     .draw_line((pos.x as i32, pos.y as i32), (end_pos.x as i32, end_pos.y as i32))
                     .unwrap();
             }
+        }
+
+        // Draw all nodes in green
+        canvas.set_draw_color(Color::RGB(0, 128, 0)); // Dark green for regular nodes
+        for i in 0..graph.node_count() {
+            let node = graph.get_node(i).unwrap();
+            let pos = node.position + crate::constants::BOARD_PIXEL_OFFSET.as_vec2();
 
-            // Draw node
-            // let color = if pacman.position.from_node_idx() == i.into() {
-            //     Color::GREEN
-            // } else if let Some(to_idx) = pacman.position.to_node_idx() {
-            //     if to_idx == i.into() {
-            //         Color::CYAN
-            //     } else {
-            //         Color::RED
-            //     }
-            // } else {
-            //     Color::RED
-            // };
-            canvas.set_draw_color(Color::GREEN);
             canvas
                 .fill_rect(Rect::new(0, 0, 3, 3).centered_on(Point::new(pos.x as i32, pos.y as i32)))
                 .unwrap();
+        }
 
-            // Draw node index
+        // Highlight connections from the nearest node in bright blue
-            // text.render(canvas, atlas, &i.to_string(), pos.as_uvec2()).unwrap();
+        if let Some(nearest_id) = nearest_node {
+            let nearest_pos = graph.get_node(nearest_id).unwrap().position + crate::constants::BOARD_PIXEL_OFFSET.as_vec2();
+
+            canvas.set_draw_color(Color::RGB(0, 255, 255)); // Bright cyan for highlighted connections
+            for edge in graph.adjacency_list[nearest_id].edges() {
+                let end_pos = graph.get_node(edge.target).unwrap().position + crate::constants::BOARD_PIXEL_OFFSET.as_vec2();
+                canvas
+                    .draw_line(
+                        (nearest_pos.x as i32, nearest_pos.y as i32),
+                        (end_pos.x as i32, end_pos.y as i32),
+                    )
+                    .unwrap();
+            }
+
+            // Highlight the nearest node in bright green
+            canvas.set_draw_color(Color::RGB(0, 255, 0)); // Bright green for highlighted node
+            canvas
+                .fill_rect(Rect::new(0, 0, 5, 5).centered_on(Point::new(nearest_pos.x as i32, nearest_pos.y as i32)))
+                .unwrap();
+
+            // Draw node ID text (small, offset to top right)
+            text_renderer.set_scale(0.5); // Small text
+            let id_text = format!("#{}", nearest_id);
+            let text_pos = glam::UVec2::new(
+                (nearest_pos.x + 4.0) as u32, // Offset to the right
+                (nearest_pos.y - 6.0) as u32, // Offset to the top
+            );
+            let _ = text_renderer.render(canvas, atlas, &id_text, text_pos);
         }
     }
+
+    /// Finds the nearest node to the given cursor position.
+    pub fn find_nearest_node(graph: &crate::entity::graph::Graph, cursor_pos: Vec2) -> Option<usize> {
+        let mut nearest_id = None;
+        let mut nearest_distance = f32::INFINITY;
+
+        for i in 0..graph.node_count() {
+            let node = graph.get_node(i).unwrap();
+            let node_pos = node.position + crate::constants::BOARD_PIXEL_OFFSET.as_vec2();
+            let distance = cursor_pos.distance(node_pos);
+
+            if distance < nearest_distance {
+                nearest_distance = distance;
+                nearest_id = Some(i);
+            }
+        }
+
+        nearest_id
+    }
 }

tests/debug_rendering.rs

@@ -0,0 +1,34 @@
+use glam::Vec2;
+use pacman::entity::graph::{Graph, Node};
+use pacman::map::render::MapRenderer;
+
+#[test]
+fn test_find_nearest_node() {
+    let mut graph = Graph::new();
+
+    // Add some test nodes
+    let node1 = graph.add_node(Node {
+        position: Vec2::new(10.0, 10.0),
+    });
+    let node2 = graph.add_node(Node {
+        position: Vec2::new(50.0, 50.0),
+    });
+    let node3 = graph.add_node(Node {
+        position: Vec2::new(100.0, 100.0),
+    });
+
+    // Test cursor near node1
+    let cursor_pos = Vec2::new(12.0, 8.0);
+    let nearest = MapRenderer::find_nearest_node(&graph, cursor_pos);
+    assert_eq!(nearest, Some(node1));
+
+    // Test cursor near node2
+    let cursor_pos = Vec2::new(45.0, 55.0);
+    let nearest = MapRenderer::find_nearest_node(&graph, cursor_pos);
+    assert_eq!(nearest, Some(node2));
+
+    // Test cursor near node3
+    let cursor_pos = Vec2::new(98.0, 102.0);
+    let nearest = MapRenderer::find_nearest_node(&graph, cursor_pos);
+    assert_eq!(nearest, Some(node3));
+}