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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use bevy::{color::palettes::basic::WHITE, prelude::*};
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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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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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    let (camera, camera_transform) = *camera_query;
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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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    // 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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    gizmos.circle_2d(point, 10., WHITE);
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}
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fn setup(mut commands: Commands) {
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    commands.spawn(Camera2d);
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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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