50 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			50 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //! This example demonstrates how to use the `Camera::viewport_to_world_2d` method.
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| 
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| use bevy::{color::palettes::basic::WHITE, prelude::*};
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| 
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| fn main() {
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|     App::new()
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|         .add_plugins(DefaultPlugins)
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|         .add_systems(Startup, setup)
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|         .add_systems(Update, draw_cursor)
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|         .run();
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| }
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| 
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| fn draw_cursor(
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|     camera_query: Single<(&Camera, &GlobalTransform)>,
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|     window: Query<&Window>,
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|     mut gizmos: Gizmos,
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| ) {
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|     let Ok(window) = window.get_single() else {
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|         return;
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|     };
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| 
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|     let (camera, camera_transform) = *camera_query;
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| 
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|     let Some(cursor_position) = window.cursor_position() else {
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|         return;
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|     };
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| 
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|     // Calculate a world position based on the cursor's position.
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|     let Ok(point) = camera.viewport_to_world_2d(camera_transform, cursor_position) else {
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|         return;
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|     };
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| 
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|     gizmos.circle_2d(point, 10., WHITE);
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| }
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| 
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| fn setup(mut commands: Commands) {
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|     commands.spawn(Camera2d);
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| 
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|     // Create a minimal UI explaining how to interact with the example
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|     commands.spawn((
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|         Text::new("Move the mouse to see the circle follow your cursor."),
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|         Node {
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|             position_type: PositionType::Absolute,
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|             top: Val::Px(12.0),
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|             left: Val::Px(12.0),
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|             ..default()
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|         },
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|     ));
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| }
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