Adds grid auto resizing when window is resized

src/main.rs

@@ -59,7 +59,8 @@ fn main()
             
             WorldPlugin {
                 grid_width: 100.,
-                grid_height: 100.
+                grid_height: 100.,
+                top_margin: 50.0
             },
             ShapePlugin
         ))
@@ -87,18 +88,6 @@ fn setup(mut commands: Commands, mut meshes: ResMut<Assets<Mesh>>, mut materials
         Agent
     ));
 
-    // Line test
-    let line = shapes::Line(Vec2::ZERO, Vec2::new(100.0, 100.0));
-    commands.spawn((
-        ShapeBundle {
-            path: GeometryBuilder::build_as(&line),
-            ..default()
-        },
-        Stroke::new(Color::ORANGE_RED, 5.0),
-        //Fill::color(Color::ORANGE_RED),
-    ));
-
-
     // UI
     // Text with multiple sections
     commands.spawn((

src/world.rs

@@ -1,7 +1,10 @@
 
-use bevy::prelude::*;
+use bevy::{prelude::*, window::WindowResized};
 use bevy_prototype_lyon::prelude::*;
 
+#[derive(Component)]
+struct GridLine;
+
 #[derive(Resource)]
 struct WorldPluginState
 {
@@ -9,6 +12,7 @@ struct WorldPluginState
     window_height: f32,
     grid_width: f32,
     grid_height: f32,
+    top_margin: f32,
 
 }
 
@@ -16,6 +20,7 @@ pub struct WorldPlugin
 {
     pub grid_width: f32,
     pub grid_height: f32,
+    pub top_margin: f32,
 }
 
 impl Plugin for WorldPlugin
@@ -33,41 +38,67 @@ impl Plugin for WorldPlugin
                     window_width: window.resolution.width(), 
                     window_height: window.resolution.height(),
                     grid_width: self.grid_width,
-                    grid_height: self.grid_height
+                    grid_height: self.grid_height,
+                    top_margin: self.top_margin,
                 })
+                .add_systems(Update, on_resize)
                 .add_systems(Startup, setup);
         }
     }
 }
 
-fn setup(mut commands: Commands, settings: Res<WorldPluginState>, mut meshes: ResMut<Assets<Mesh>>, mut materials: ResMut<Assets<ColorMaterial>>)
+fn setup(mut commands: Commands, settings: Res<WorldPluginState>)
 {
-    // Camera
-    //commands.spawn(Camera2dBundle::default());
 
     // Add Grid
-    // let cell_width = settings.window_width / settings.grid_width;
-    // let cell_height = settings.window_height / settings.grid_height;
-    // let line_size = 2;
-    // for i in 0..settings.grid_width as i32
-    // {
-    //     for j in 0..settings.grid_height as i32
-    //     {
-            
-    //     }
-    // }
+    let cell_width = settings.window_width / (settings.grid_width - 1.0);
+    let cell_height = (settings.window_height -  settings.top_margin) / (settings.grid_height - 1.0);
+    let line_size = 2.0;
+    let half_screen_width = settings.window_width / 2.0;
+    let half_screen_height = (settings.window_height - settings.top_margin) / 2.0;
+    for i in 0..settings.grid_width as i32
+    {
+        let point_a = Vec2::new(i as f32 * cell_width - half_screen_width, -half_screen_height - settings.top_margin);
+        let point_b = Vec2::new(i as f32 * cell_width - half_screen_width, half_screen_height - settings.top_margin);
+        add_line(&mut commands, point_a, point_b, line_size);        
+    }
+
+    for i in 0..settings.grid_height as i32
+    {
+        let point_a = Vec2::new(-half_screen_width, i as f32 * cell_height - half_screen_height - settings.top_margin);
+        let point_b = Vec2::new(half_screen_width, i as f32 * cell_height - half_screen_height - settings.top_margin);
+        add_line(&mut commands, point_a, point_b, line_size);      
+    }
 }
 
-// fn add_line(mut commands: Commands, point_a: Vec2, point_b: Vec2, line_size: i32)
-// {
+fn add_line(commands: &mut Commands, point_a: Vec2, point_b: Vec2, line_size: f32)
+{
+    let line = shapes::Line(point_a, point_b);
 
+    commands.spawn((
+        ShapeBundle {
+            path: GeometryBuilder::build_as(&line),
+            ..default()
+        },
+        Stroke::new(Color::BLACK, line_size),
+        GridLine,
+    ));
+}
+
+fn on_resize(mut commands: Commands, mut settings: ResMut<WorldPluginState>, mut resize_reader: EventReader<WindowResized>, mut grid: Query<(Entity, &GridLine)> )
+{
+    for e in resize_reader.iter() 
+    {
+        // When resolution is being changed
+        // info!("new window size: {:.1} x {:.1}", e.width, e.height);
+        settings.window_width = e.width;
+        settings.window_height = e.height;
+    }
+
+    for (entity, line) in &grid
+    {
+        commands.entity(entity).despawn();
+    }
 
-//     commands.spawn(MaterialMesh2dBundle {
-//         mesh: meshes
-//             .add(shape::Quad::new(Vec2::new(cell_width * i, cell_height * j)).into())
-//             .into(),
-//         material: materials.add(ColorMaterial::from(Color::BLACK)),
-//         transform: Transform::from_translation(Vec3::new(50., 0., 0.)),
-//         ..default()
-//     });
-// }
+    setup(commands, settings.into());
+}