Fixed line clearing bug

src/bin/tetris/main.rs

@@ -1,3 +1,4 @@
+#![feature(try_blocks)]
 // Bevy basically forces "complex types" with Querys
 #![allow(clippy::type_complexity)]
 
@@ -27,39 +28,44 @@ fn main() {
         .add_systems(Startup, (init_world, init_debug_ui, init_ui))
         // Input and basic systems
         .add_systems(
-            Update, (
+            Update,
+            (
                 kb_input.run_if(on_event::<KeyboardInput>),
                 toggle_state_visibility::<GameState>.run_if(state_changed::<GameState>),
-            )
+            ),
         )
         .add_systems(
             Update,
             (
-                update_next_shapes.run_if(resource_changed::<ShapesBuffer>.or(resource_added::<ShapesBuffer>)),
+                update_next_shapes
-                add_piece.run_if(not(any_with_component::<Shape>)).after(update_next_shapes),
+                    .run_if(resource_changed::<ShapesBuffer>.or(resource_added::<ShapesBuffer>)),
+                add_piece
+                    .run_if(not(any_with_component::<Shape>))
+                    .after(update_next_shapes),
                 update_shape_blocks
                     .run_if(any_component_added::<Shape>.or(any_component_changed::<Shape>)),
-
                 falling
                     .run_if(in_state(GameState::Falling))
                     .run_if(clock_cycle(1.0)),
                 update_position.run_if(any_component_changed::<GridPosition>),
-
                 deactivate_shape.run_if(any_component_removed::<Shape>),
-
+                check_line_removal,
                 // Clearing lines systems
                 clear_line.run_if(any_component_changed::<LineBlocks>),
-                adjust_block_lines.run_if(any_component_changed::<Line>).after(clear_line),
+                adjust_block_lines
+                    .run_if(any_component_changed::<Line>)
+                    .after(clear_line),
             ),
         )
         // UI systems
-        .add_systems(Update,
+        .add_systems(
+            Update,
             (
                 sync_resource_to_ui::<ShapesBuffer>.run_if(resource_changed::<ShapesBuffer>),
                 sync_resource_to_ui::<Score>.run_if(resource_changed::<Score>),
                 sync_singleton_to_ui::<Shape>.run_if(any_component_changed::<Shape>),
                 sync_singleton_to_ui::<Orientation>.run_if(any_component_changed::<Orientation>),
-            )
+            ),
         )
         .add_systems(Update, draw_grid)
         .run();
@@ -304,31 +310,25 @@ fn init_ui(mut commands: Commands) {
             BackgroundColor(BLACK.into()),
         ))
         .with_children(|parent| {
-            parent.spawn((
+            parent
-                Node {
+                .spawn((Node {
                     flex_direction: FlexDirection::Column,
                     align_items: AlignItems::Center,
                     ..default()
-                },
+                },))
-            )).with_children(|parent|{
+                .with_children(|parent| {
                     parent.spawn(Text::new("Next:"));
-                parent.spawn((
+                    parent.spawn((Text::new("???"), SyncResource::<ShapesBuffer>::default()));
-                    Text::new("???"),
-                    SyncResource::<ShapesBuffer>::default(),
-                ));
                 });
-            parent.spawn((
+            parent
-                Node {
+                .spawn((Node {
                     flex_direction: FlexDirection::Column,
                     align_items: AlignItems::Center,
                     ..default()
-                },
+                },))
-            )).with_children(|parent|{
+                .with_children(|parent| {
                     parent.spawn(Text::new("Score:"));
-                parent.spawn((
+                    parent.spawn((Text::new("???"), SyncResource::<Score>::default()));
-                    Text::new("???"),
-                    SyncResource::<Score>::default(),
-                ));
                 });
         });
 
@@ -563,7 +563,7 @@ fn update_shape_blocks(
     visuals: Res<Visuals>,
 ) {
     query.iter().for_each(|(e, s, o, center)| {
-        info!("Setting piece: {e:?} {o:?} {center:?}\n{}", s.as_ascii());
+        debug!("Setting piece: {e:?} {o:?} {center:?}\n{}", s.as_ascii());
 
         if blocks.is_empty() {
             let mesh = Mesh2d(visuals.mesh.clone());
@@ -678,16 +678,17 @@ fn add_piece(mut commands: Commands, mut shapes: ResMut<ShapesBuffer>) {
 /// When a line reaches 10 blocks, clear it
 fn clear_line(
     changed_lines: Query<Entity, Changed<LineBlocks>>,
-    mut lines: Query<(Entity, &LineBlocks, &mut Line)>,
+    mut lines: Query<&mut Line>,
+    line_blocks: Query<&LineBlocks>,
     mut score: ResMut<Score>,
     mut commands: Commands,
 ) {
-    let cleared_lines: Vec<usize> = changed_lines
+    let mut cleared_lines: Vec<usize> = changed_lines
         .iter()
-        .filter_map(|e| lines.get(e).ok())
+        .filter_map(|e| try { (Some(e)?, line_blocks.get(e).ok()?, lines.get(e).ok()?) } )
         .filter_map(|(e, lb, Line(i))| {
             if lb.0.len() == 10 {
-                commands.entity(e).despawn_related::<LineBlocks>();
+                commands.entity(e).despawn_related::<LineBlocks>().insert(LineBlocks::default());
                 score.0 += 1;
                 info!("New score: {:?}", score.0);
                 Some(*i)
@@ -695,23 +696,41 @@ fn clear_line(
                 None
             }
         })
+        .sorted()
         .collect();
 
+    if !cleared_lines.is_empty() {
         info!("Cleared lines: {:?}", cleared_lines);
 
-    for (idx, cleared_line_number) in cleared_lines.into_iter().sorted().enumerate() {
+        #[cfg(debug_assertions)]
-        info!("Processing line {cleared_line_number} ({idx})");
+        {
-        let cleared_line_number = cleared_line_number - idx;
+            debug_assert_eq!(lines.iter().count(), 20, "There should be 20 lines");
-        lines.iter_mut().sorted_by(|(_, _, i), (_, _, j)| i.0.cmp(&j.0)).for_each(|(_, _, mut l)| {
+            // Check that all line numbers are present
-            let dest = if l.0 > cleared_line_number {
+            lines.iter().map(|Line(i)| i).sorted().enumerate().for_each(|(i, line_num)| {
-                l.0 - 1
+                debug_assert_eq!(i, *line_num, "Line numbers should match their sorted index");
-            } else if l.0 == cleared_line_number {
+            });
-                Y_MAX - 1
+        }
+
+        let original_cleared_lines_len = cleared_lines.len();
+
+        // Iterate over all lines in reverse sorted order (largest to smallest)
+        lines
+            .iter_mut()
+            .sorted_by(|i, j| i.0.cmp(&j.0))
+            .rev()
+            .for_each(|mut l| {
+                // If the current index is in the set of cleared lines, move it to the top
+                // Otherwise, move it down by the number of cleared lines
+                if cleared_lines.contains(&l.0) {
+                    // Move to the N-offset line number (top, top-1, etc)
+                    let offset = original_cleared_lines_len - cleared_lines.len();
+                    info!("Moving line {:?}->{:?}", l.0, Y_MAX - 1 - offset);
+                    l.0 = Y_MAX - 1 - offset;
+                    cleared_lines.pop();
                 } else {
-                l.0
+                    info!("Moving line {:?}->{:?}", l.0, l.0 - cleared_lines.len());
-            };
+                    l.0 -= cleared_lines.len();
-            info!("Moving line {:?} to {:?}", l, dest);
+                }
-            l.0 = dest;
             });
     }
 }
@@ -721,17 +740,6 @@ fn adjust_block_lines(
     parent: Query<&LineBlocks>,
     mut blocks: Query<&mut GridPosition>,
 ) {
-    #[cfg(debug_assertions)]
-    {
-        // Check that all line numbers are present
-        let expected_line_numbers  = 0..Y_MAX;
-        let actual_line_numbers = query.iter().map(|(_, Line(i))| i).sorted();
-        query.iter().map(|(_, Line(i))| i).sorted().for_each(|i| info!("Line #: {i}"));
-        std::iter::zip(expected_line_numbers, actual_line_numbers).for_each(|(a, b)| {
-            debug_assert_eq!(a as usize, *b);
-        });
-    }
-
     query.iter().for_each(|(e, Line(i))| {
         parent.iter_descendants(e).for_each(|block| {
             if let Ok(mut gp) = blocks.get_mut(block) {
@@ -767,7 +775,7 @@ fn movement(
             Movement::Right => (center.with_offset(1, 0), *this_shape),
             Movement::Rotate => (Ok(*center), this_shape.rotated()),
         };
-        info!(
+        debug!(
             "Proposed change: {:?}\n{}",
             new_center,
             new_shape.as_ascii()
@@ -819,6 +827,14 @@ fn movement(
     }
 }
 
+fn check_line_removal(
+    mut events: RemovedComponents<Line>,
+) {
+    events.read().for_each(|e| {
+        info!("Line entity {:?} removed", e);
+    });
+}
+
 // TODO: Just despawn?
 fn deactivate_shape(
     mut events: RemovedComponents<Shape>,