Проектная работа - WIP

snake-game/src/gameplay.rs

@@ -1,6 +1,6 @@
 use bevy::prelude::*;
 
-use crate::domain::{Direction, Head};
+use crate::domain::{Direction, GRID_SIZE, Head, Inert, Velocity};
 
 pub fn head_rotation(
     input: Res<ButtonInput<KeyCode>>,
@@ -20,4 +20,45 @@ pub fn head_rotation(
     }
 }
 
-pub fn moving() {}
+pub fn moving(time: Res<Time>, query: Query<(&mut Transform, &mut Inert, &Direction, &Velocity)>) {
+    for (mut transform, mut inert, direction, Velocity(velocity)) in query.into_iter() {
+        let delta = velocity * time.delta_secs();
+        if inert.0 == *direction {
+            todo!()
+        } else {
+            let inert_vec = inert.0.vector();
+            let delta_vec = inert_vec * delta;
+            let ovf_vec = vec2(
+                get_overflow(GRID_SIZE as f32, transform.translation.x, delta_vec.x),
+                get_overflow(GRID_SIZE as f32, transform.translation.y, delta_vec.y),
+            );
+
+            todo!()
+        }
+        todo!()
+    }
+}
+
+fn get_overflow(grid: f32, coord: f32, delta: f32) -> f32 {
+    let rem = coord % grid;
+    let rem = if rem < 0.0 { grid + rem } else { rem };
+    let new = rem + delta;
+    if new >= 0.0 && new <= grid {
+        0.0
+    } else {
+        new % grid
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::gameplay::get_overflow;
+
+    #[test]
+    fn test_get_overflow() {
+        assert_eq!(get_overflow(5.0, -6.0, 3.0), 2.0);
+        assert_eq!(get_overflow(5.0, 6.0, 3.0), 0.0);
+        assert_eq!(get_overflow(5.0, -6.0, -3.0), 0.0);
+        assert_eq!(get_overflow(5.0, 6.0, -3.0), -2.0);
+    }
+}