add iterator to world

src/activities/overworld/worldgen.rs

@@ -56,10 +56,18 @@ pub struct Chunk {
 }
 
 impl Chunk {
-	fn get_tile(&self, local_chunk_coords: UVec2) -> Option<&Tile> {
+	pub fn get_tile(&self, local_chunk_coords: UVec2) -> Option<&Tile> {
 		self.tiles
 			.get((local_chunk_coords.y * CHUNK_SIZE + local_chunk_coords.x) as usize)
 	}
+
+	/// iterate over all tiles and its local chunk coords
+	pub fn iter_tiles(&self) -> impl Iterator<Item = (UVec2, &Tile)> {
+		self.tiles.iter().enumerate().map(|(i, tile)| {
+			let i = i as u32;
+			(UVec2::new(i % CHUNK_SIZE, i / CHUNK_SIZE), tile)
+		})
+	}
 }
 
 #[derive(Debug, Default)]
@@ -70,7 +78,7 @@ pub struct Overworld {
 impl Overworld {
 	/// Return a [`Tile`] at the given world coordinates, or `None` if that tile has not
 	/// been generated yet.
-	fn get_tile(&self, world_coords: IVec2) -> Option<&Tile> {
+	pub fn get_tile(&self, world_coords: IVec2) -> Option<&Tile> {
 		let tile_coords = IVec2 {
 			x: world_coords.x.div_euclid(CHUNK_SIZE as _),
 			y: world_coords.y.div_euclid(CHUNK_SIZE as _)
@@ -87,4 +95,15 @@ impl Overworld {
 	fn get_or_generate_tile(&self, world_coords: IVec2) -> &Tile {
 		unimplemented!()
 	}
+
+	/// iterate over all tiles and its global coords
+	pub fn iter_tiles(&self) -> impl Iterator<Item = (IVec2, &Tile)> {
+		self.chunks.iter().flat_map(|(chunk_coords, chunk)| {
+			chunk.iter_tiles().map(|(local_coords, tile)| {
+				// never fail because chunksize fits alswas into i32
+				let local_coords: IVec2 = local_coords.try_into().unwrap();
+				(local_coords + (*chunk_coords * CHUNK_SIZE as i32), tile)
+			})
+		})
+	}
 }