Adjusted the piece origins so they rotate better. Added some positional adjusting to make space for rotated pieces.

src/game/prefab.rs

@@ -17,7 +17,7 @@ use super::{PIXEL_SCALE, grid::*, tetris::*};
 )]
 pub struct DemoCamera2d;
 
-#[derive(Component, Clone, Copy, Debug, Default, Reflect)]
+#[derive(Component, Clone, Copy, Debug, Default, PartialEq, Eq, Reflect)]
 #[reflect(Component)]
 pub enum PieceType {
     /// ......
@@ -59,27 +59,17 @@ impl PieceType {
 
     pub fn block_positions(&self) -> [Vector2I; 4] {
         match self {
-            Self::I => [(0, 0), (1, 0), (2, 0), (3, 0)],
+            Self::I => [(-1, 0), (0, 0), (1, 0), (2, 0)],
-            Self::T => [(0, 0), (1, 0), (1, 1), (2, 0)],
+            Self::T => [(-1, 0), (0, 0), (0, 1), (1, 0)],
-            Self::L => [(0, 0), (1, 0), (2, 0), (2, 1)],
+            Self::L => [(-1, 0), (0, 0), (1, 0), (1, 1)],
-            Self::J => [(0, 0), (0, 1), (1, 0), (2, 0)],
+            Self::J => [(-1, 0), (-1, 1), (0, 0), (1, 0)],
-            Self::S => [(0, 0), (1, 0), (1, 1), (2, 1)],
+            Self::S => [(-1, 0), (0, 0), (0, 1), (1, 1)],
-            Self::Z => [(1, 0), (1, 1), (0, 1), (2, 0)],
+            Self::Z => [(-1, 1), (0, 0), (0, 1), (1, 0)],
             Self::Square => [(0, 0), (0, 1), (1, 0), (1, 1)],
         }
         .map(|pos| pos.into())
     }
 
-    // pub fn width(&self) -> i32 {
-    //     let x_positions: Vec<_> = self.block_positions().iter().map(|pos| pos.x).collect();
-    //     if x_positions.is_empty() {
-    //         return 0;
-    //     }
-    //     let min = x_positions.iter().min().unwrap();
-    //     let max = x_positions.iter().max().unwrap();
-    //     max - min + 1
-    // }
-
     pub fn name(&self) -> String {
         match self {
             Self::I => "I-piece",

src/game/systems/movement.rs

@@ -1,7 +1,7 @@
 use bevy::prelude::*;
 
 use crate::{
-    game::{grid::*, tetris::*},
+    game::{grid::*, prefab::*, tetris::*},
     util::Vector2I,
 };
 
@@ -21,9 +21,11 @@ pub fn apply_gravity(
     }
 }
 
+#[allow(clippy::type_complexity)]
 pub fn apply_piece_movement(
     mut piece_query: Query<(
         &PieceControls,
+        Option<&PieceType>,
         Option<&mut Gravity>,
         Entity,
         &ChildOf,
@@ -33,7 +35,9 @@ pub fn apply_piece_movement(
     mut transform_query: Query<(&mut GridTransform, Has<Block>)>,
     mut commands: Commands,
 ) {
-    for (controls, maybe_gravity, entity, parent, children) in piece_query.iter_mut() {
+    'piece_loop: for (controls, maybe_piece_type, maybe_gravity, entity, parent, children) in
+        piece_query.iter_mut()
+    {
         let game_entity = parent.parent();
         let (collisions, game_area) = game_query.get(game_entity).unwrap();
 
@@ -99,6 +103,10 @@ pub fn apply_piece_movement(
         }
 
         {
+            // Skip rotating square piece
+            if maybe_piece_type.is_some_and(|piece_type| *piece_type == PieceType::Square) {
+                continue;
+            }
             let cast_shape = |pos, blocks| {
                 collisions.cast_shape(pos, blocks) || !game_area.is_shape_inside(pos, blocks)
             };
@@ -113,15 +121,22 @@ pub fn apply_piece_movement(
                     .collect::<Vec<Vector2I>>()
             };
             let piece_pos = transform_query.get(entity).unwrap().0.translation;
+
             if let Some(rotation) = controls.rotation {
+                let offsets = vec![(0, 0), (1, 0), (-1, 0), (2, 0), (-2, 0)];
                 let rotated = rotate_slice(&blocks, rotation);
-                if !cast_shape(piece_pos, &rotated) {
+                for offset in offsets {
-                    for child in children.iter() {
+                    if !cast_shape(piece_pos + offset.into(), &rotated) {
-                        if let Ok((mut transform, has_block)) = transform_query.get_mut(child) {
+                        transform_query.get_mut(entity).unwrap().0.translation =
-                            if has_block {
+                            piece_pos + offset.into();
-                                transform.translation = rotate(transform.translation, rotation);
+                        for child in children.iter() {
+                            if let Ok((mut transform, has_block)) = transform_query.get_mut(child) {
+                                if has_block {
+                                    transform.translation = rotate(transform.translation, rotation);
+                                }
                             }
                         }
+                        continue 'piece_loop;
                     }
                 }
             }