Fixed panicky queries

Co-authored-by: Sebastian J. Hamel <[email protected]>

src/debug.rs

@@ -28,9 +28,9 @@ fn draw_viewbox(
     query_cam: Query<(&Camera, &GlobalTransform, &OrthographicProjection), With<Camera2d>>,
     mut gizmos: Gizmos,
 ) {
-    const RED_X_SIZE: f32 = 8.0;
+    let Ok((camera, view, projection)) = query_cam.get_single() else { return };
 
-    let (camera, view, projection) = query_cam.single();
+    const RED_X_SIZE: f32 = 8.0;
 
     // Show world-space vectors
     for (vector, transform, _) in query_world

src/main.rs

@@ -63,13 +63,13 @@ fn camera_system(
     mut q: Query<&mut OrthographicProjection, With<Camera>>,
     time: Res<Time>,
 ) {
-    let mut projection = q.single_mut();
+    let Ok(mut projection) = q.get_single_mut() else { return };
+    let Ok(mut camera_transform) = query_cam.get_single_mut() else { return };
+    let Ok((&(mut target_transform), vector)) = query.get_single_mut() else { return };
 
     // Zoom in & out to demonstrate scalability and show the vector graphic's viewbox/anchor point
     projection.scale = 2.0 * time.elapsed_seconds().cos();
 
-    let mut camera_transform = query_cam.single_mut();
-    let (&(mut target_transform), vector) = query.single_mut();
     if let Some(vector) = vectors.get(&vector) {
         target_transform.translation.y += vector.height * target_transform.scale.y / 2.0;
         camera_transform.translation = target_transform.translation;
@@ -82,7 +82,7 @@ fn drag_and_drop(
     asset_server: ResMut<AssetServer>,
     mut dnd_evr: EventReader<FileDragAndDrop>,
 ) {
-    let (_, mut vector) = query.single_mut();
+    let Ok((_, mut vector)) = query.get_single_mut() else { return };
 
     for ev in dnd_evr.iter() {
         if let FileDragAndDrop::DroppedFile { path_buf, .. } = ev {

src/renderer/prepare.rs

@@ -70,7 +70,7 @@ pub fn prepare_vector_affines(
     render_vector_assets: Res<RenderAssets<VelloVector>>,
     pixel_scale: Res<ExtractedPixelScale>,
 ) {
-    let (camera, view) = camera.single();
+    let Ok((camera, view)) = camera.get_single() else { return };
     let size_pixels: UVec2 = camera.physical_viewport_size.unwrap();
     let (pixels_x, pixels_y) = (size_pixels.x as f32, size_pixels.y as f32);
     for (entity, render_vector) in render_vectors.iter_mut() {
@@ -151,7 +151,7 @@ pub fn prepare_text_affines(
     render_texts: Query<(Entity, &ExtractedRenderText)>,
     pixel_scale: Res<ExtractedPixelScale>,
 ) {
-    let (camera, view) = camera.single();
+    let Ok((camera, view)) = camera.get_single() else { return };
     let size_pixels: UVec2 = camera.physical_viewport_size.unwrap();
     let (pixels_x, pixels_y) = (size_pixels.x as f32, size_pixels.y as f32);
     for (entity, render_text) in render_texts.iter() {

src/rendertarget.rs

@@ -61,7 +61,7 @@ pub fn resize_rendertargets(
     mut target_materials: ResMut<Assets<SSTargetMaterial>>,
     windows: Query<&Window>,
 ) {
-    let window = windows.single();
+    let Ok(window) = windows.get_single() else { return };
     if window_resize_events.iter().last().is_some() {
         let size = Extent3d {
             width: window.resolution.physical_width(),
@@ -115,7 +115,7 @@ pub fn setup_ss_rendertarget(
     // query_vectors: Query<Entity, Added<Handle<VelloVector>>>,
     mut render_target_mesh_handle: Local<Option<Handle<Mesh>>>,
 ) {
-    let window = windows.single();
+    let Ok(window) = windows.get_single() else { return };
 
     let mesh_handle = render_target_mesh_handle.get_or_insert_with(|| {
         let mut rendertarget_quad = Mesh::new(PrimitiveTopology::TriangleList);