Improved RoomCoordinate and RoomXY, new RoomOffset for optimize…

…d arithmetic (#543)

CHANGELOG.md

@@ -11,6 +11,11 @@ Unreleased
 
 - Add `s7_score_cycle_at_tick` seasonal constant function to reflect the reversed score cycle in
   season 7
+- Add indexing implementations for `RoomCoordinate` and `RoomXY` as well as `XMajor` / `YMajor`
+  wrapper types to control which indexing approach is used; switch to using these for
+  `LocalCostMatrix` and `LocalRoomTerrain`
+- Add `RoomOffset` type representing a difference between coordinates and associated functions
+  for manipulating `RoomCoordinate` and `RoomXY`
 
 0.22.0 (2024-08-27)
 ===================

src/constants/extra.rs

@@ -270,10 +270,15 @@ pub const ROOM_VISUAL_PER_ROOM_SIZE_LIMIT: u32 = 500 * 1024;
 /// [`Room`]: crate::objects::Room
 pub const ROOM_SIZE: u8 = 50;
 
+/// ['ROOM_SIZE'] cast into a `usize`, for indexing convenience.
+///
+/// ['ROOM_SIZE']: self::ROOM_SIZE
+pub const ROOM_USIZE: usize = ROOM_SIZE as usize;
+
 /// The number of total tiles in each [`Room`] in the game
 ///
 /// [`Room`]: crate::objects::Room
-pub const ROOM_AREA: usize = (ROOM_SIZE as usize) * (ROOM_SIZE as usize);
+pub const ROOM_AREA: usize = ROOM_USIZE * ROOM_USIZE;
 
 /// Owner username of hostile non-player structures and creeps which occupy
 /// sector center rooms.

src/local/cost_matrix.rs

@@ -8,7 +8,7 @@ use crate::{
     traits::{CostMatrixGet, CostMatrixSet},
 };
 
-use super::{linear_index_to_xy, xy_to_linear_index, Position, RoomXY};
+use super::{linear_index_to_xy, Position, RoomXY, XMajor};
 
 /// A matrix of pathing costs for a room, stored in Rust memory.
 ///
@@ -121,19 +121,29 @@ impl From<&CostMatrix> for LocalCostMatrix {
     }
 }
 
+impl AsRef<XMajor<u8>> for LocalCostMatrix {
+    fn as_ref(&self) -> &XMajor<u8> {
+        XMajor::from_flat_ref(&self.bits)
+    }
+}
+
+impl AsMut<XMajor<u8>> for LocalCostMatrix {
+    fn as_mut(&mut self) -> &mut XMajor<u8> {
+        XMajor::from_flat_mut(&mut self.bits)
+    }
+}
+
 impl Index<RoomXY> for LocalCostMatrix {
     type Output = u8;
 
     fn index(&self, xy: RoomXY) -> &Self::Output {
-        // SAFETY: RoomXY is always a valid coordinate.
-        unsafe { self.bits.get_unchecked(xy_to_linear_index(xy)) }
+        &self.bits[xy.x][xy.y]
     }
 }
 
 impl IndexMut<RoomXY> for LocalCostMatrix {
     fn index_mut(&mut self, xy: RoomXY) -> &mut Self::Output {
-        // SAFETY: RoomXY is always a valid coordinate.
-        unsafe { self.bits.get_unchecked_mut(xy_to_linear_index(xy)) }
+        &mut self.bits[xy.x][xy.y]
     }
 }
 

src/local/object_id/raw.rs

@@ -69,7 +69,7 @@ impl Serialize for RawObjectId {
 
 struct RawObjectIdVisitor;
 
-impl<'de> Visitor<'de> for RawObjectIdVisitor {
+impl Visitor<'_> for RawObjectIdVisitor {
     type Value = RawObjectId;
 
     fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {