added neighbours to hexmap

src/hexmap.rs

@@ -9,6 +9,15 @@ pub struct HexMap {
     pix_tile_off: Vec2<i32>,
 }
 
+pub enum Direction {
+    North,
+    NorthEast,
+    SouthEast,
+    South,
+    SouthWest,
+    NorthWest,
+}
+
 impl HexMap {
     //pub static
     //pix_tile_off: x offset per tile, up/down alternating y offset on x axis
@@ -21,9 +30,28 @@ impl HexMap {
         }
     }
 
+    pub fn get_neighbour(coord: Vec2<i32>, dir: Direction) -> Vec2<i32> {
+        let yoff = coord.x % 2;
+        (match dir {
+            Direction::North => Vec2 { x: 0, y: -1 },
+            Direction::NorthEast => Vec2 { x: 1, y: -1 + yoff },
+            Direction::SouthEast => Vec2 { x: 1, y: 0 + yoff },
+            Direction::South => Vec2 { x: 0, y: 1 },
+            Direction::SouthWest => Vec2 { x: -1, y: 0 + yoff },
+            Direction::NorthWest => Vec2 {
+                x: -1,
+                y: -1 + yoff,
+            },
+        }) + coord
+    }
+
     //pub
     pub fn get(&self, coord: Vec2<i32>) -> i32 {
-        self.data[self.coord_to_idx(coord)]
+        if !self.is_valid_coord(coord) {
+            -1
+        } else {
+            self.data[self.coord_to_idx(coord)]
+        }
     }
 
     pub fn pixel_to_coord(&self, pixel: Vec2<i32>) -> Vec2<i32> {
@@ -66,6 +94,10 @@ impl HexMap {
         })
     }
 
+    pub fn is_valid_coord(&self, coord: Vec2<i32>) -> bool {
+        coord.x >= 0 && coord.y >= 0 && coord.x < self.size.x && coord.y < self.size.y
+    }
+
     pub fn set(&mut self, coord: Vec2<i32>, val: i32) {
         let idx = self.coord_to_idx(coord);
         self.data[idx] = val;